Skocz do pozycji: 1.

Tytuł:

Mafic and ultramafic associations of ophiolite (possible Tethyan ophiolite) in the Panlin-Pyaunggaung area, Mogok, Myanmar

Autorzy:

Myint, Tin Aung
Ko, Mi Mi
Thin, Aung Kyaw
Peng, Touping

Powiązania:

https://bibliotekanauki.pl/articles/24202092.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Myanmar

Opis:

The Panlin-Pyaunggaung area is situated within the Mogok Metamorphic Belt (MMB) in Myanmar. The MMB extends for over 1,000 km along the western part of ShanThai Terrene (also known as Sibumasu Terrene) from the Andaman Sea as a narrow linear belt, then sharply bends east-northeastward through the northern part of Mogok including Panlin-Pyaunggaung area toward the China-Myanmar border and finally further northward into the East Himalayan Syntaxis. It comprises a sequence of regionally high-grade metamorphic rocks, representing the amphibolite-granulite facies grade belt intruded by granitoid rocks of various ages. Metamorphic rock units exposed in the area are marbles, calc-silicates and gneisses. Igneous rocks are peridotite, dunite, serpentinite, gabbro, granite, leucogranite, syenite and pegmatite. The ultramafic rocks (Pyaunggaung peridotites) mainly occur in the northern part of Mogok and have been considered as tectonites. Ophiolite sequence which consists, from bottom to top, of upper mantle peridotites/dunites, layered ultramafic-mafic rocks, layered gabbros, and felsic dikes occurs in the area indicating the typical lower part of ophiolite suite. The present ultramafities are mainly dunite-peridotite (harzburgitic or dunitic composition). Magnetic susceptibility of ophiolites reflects the highest point (39.75 ∙ 10−3 SI units). It is found that the chromite spinel observed in ophiolites and it contains high Pm, Cr, Ni & V. These criteria suggested that ophiolites in the area were deep seated origin coming from the upper mantle source. Panlin-Pyaunggaung Ophiolites in the area fall within the field of the Alpine-type peridotite. High Ni–Low Al content corresponds to the suprasubduction zone (SSZ) ophiolites and might have a similar tectonic stetting of Tagaung-Myitkyina Ophiolite Belt in Myanmar.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 53--53
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:

Mid-oceanic seamount carbonates in Eastern Paleotethyan suture zones

Autorzy:

Ueno, Katsumi

Powiązania:

https://bibliotekanauki.pl/articles/24202095.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
carbonates

Opis:

Mid-oceanic seamount-capping (atoll-type) carbonates make a popular stratigraphic entity in the geology of Japan since they are often seen as various-sized (but usually large and typically huge) exotic blocks within ancient (mostly Permian to early Cretaceous) accretionary complexes distributed in the Japanese Islands. These carbonates consist of very thick and pure (in the sense that it lacked input of continental detritus), usually massive and fossiliferous, shallow-marine limestone, and rest on oceanic-island basalts (OIB) of hot-spot origin, formed in the Panthalassa Ocean. Stratigraphically, they comprise a unique sedimentary succession that records long-term (sometimes over 80 myr.), continuous, shallow-marine environmental and biotic changes during late Paleozoic and early Mesozoic times of the oceanic sector with a stable tectonic setting, and can only be found within the accretionary orogen in the context of Ocean Plate Stratigraphy (OPS). Thus, the mid-oceanic seamount carbonate succession is a “surefire” geological item for the investigation of the ancient subduction zone and suture zone. On the basis of my research expertise working on these mid-oceanic carbonates in Japan over many years, especially in the Carboniferous–Permian Akiyoshi Limestone known as the most typical seamount-capping atoll-type carbonate body in the Panthalassa Ocean, I exported this, essentially “made-in-Japan” and “cultivated-in-Japan”, geological concept of “mid-oceanic seamount carbonates within the accretionary orogen” to Southeast Asian geology, for better understanding the general geotectonic subdivision and evolution of the relevant region, especially for clarifying the position of Paleotethyan suture zones and the geohistory of the Eastern Paleotethys Ocean. In today’s Southeast Asia, Paleotethyan mid-oceanic seamount carbonates are distributed in Northern Thailand and western Yunnan, SW China where Gondwana and Tethys meet together. Of these two regions, Northern Thailand is subdivided into three basic geotectonic domains; from east to west the Cathaysian Indochina Block, Sukhothai Zone (a Permian–Triassic island arc developed along the Indochina margin), and peri-Gondwanan Sibumasu Block. In the eastern part of Sibumasu, a geotectonically peculiar area called the Inthanon Zone can be identified on which Paleotethyan oceanic rocks including the Carboniferous–Permian Doi Chiang Dao Limestone of mid-oceanic seamount origin are widely distributed. This limestone succession, sometimes making kilometer-sized huge limestone blocks, is estimated to be 1000 m thick or more, and consists mostly of shallow-marine fossiliferous massive limestone without siliciclastic intercalation throughout. Basalts having intra-plate (oceanic volcanic island) geochemistry are observed at the base of the succession. Foraminifers, especially fusulines, are the fundamental fossil group for establishing its detailed chronostratigraphy, and they clarified that the limestone continuously accumulated from the Visean (middle Early Carboniferous) to the Changhsingian (latest Permian) over the time of 90 myr. In western Yunnan, the Changning–Menglian Belt is defined between the Lincang Massif (a Permian–Triassic island arc system formed along the easterly Simao Block with Cathaysian affinity) to the east and the peri-Gondwanan Baoshan Block to the west. The Changning–Menglian Belt, subdivided into the East, Central, and West zones, entirely has been regarded as a closed remnant (suture zone) of the Paleotethys Ocean, but actually it is only in the Central Zone where oceanic rocks are distributed. Paleotethyan mid-oceanic carbonates in this belt are called the Banka Limestone, which is over 1200 m in total thickness and generally massive and pure, being free from continental siliciclastic input for the entire succession spanning nearly 90 myr. Foraminiferal (mostly fusuline) biostratigraphy suggested continuous deposition ranging from the Visean to the Changhsingian without significant hiatus in the succession. Thus, the Banka Limestone in western Yunnan is exactly correlated in view of lithostratigraphy, chronostratigraphy, and tectonostratigraphy to the Doi Chiang Dao Limestone in Northern Thailand. In a broad geotectonic perspective, the Paleotethyan oceanic rocks including the Doi Chiang Dao Limestone, distributed in the Inthanon Zone are considered to form various-sized tectonic outliers upon autochthonous basement rocks of Sibumasu now, which consists of early Paleozoic– Triassic sedimentary, meta-sedimentary, and igneous intrusive rocks. Similarly, those distributed in the Central Zone of the Changning–Menglian Belt are structurally resting by almost flat-lying faults (thrusts) upon siliciclastic rocks of the West and/or East zones, which presumably represent passive-margin (continental slope) sediments of the westerly, Gondwanan Baoshan Block. These mid-oceanic rocks are interpreted to have been once incorporated within an accretionary prism formed by the subduction of the Paleotethyan oceanic lithosphere beneath the Permian–Triassic island arc system represented by the Lincang Massif–Sukhothai Zone. The resultant collision of the Cimmerian (peri-Gondwanan) Sibumasu–Baoshan Block to the Cathaysian Indochina–Simao Block, thus the closure of the Paleotethys Ocean in present-day Southeast Asia, at around Triassic–Jurassic boundary time emplaced rocks of the accretionary complexes (containing Paleotethyan oceanic rocks as exotic blocks) onto the marginal part of the Sibumasu–Baoshan Block as large thrust sheets (nappe).

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 75--76
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:

Unraveling the collisional history of the Western Carpathians through deep geophysical sounding

Autorzy:

Soni, Tanishka
Schiffer, Chrystian
Mazur, Stanisław

Powiązania:

https://bibliotekanauki.pl/articles/24202097.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Carpathians
Tethys
terranes

Opis:

The ALpine-CArpathian-PAnnonian (ALCAPA) block is one of the terranes involved in the Alpine-Tethys suture along with the North European Plate. In the Western Carpathians, this suture is supposed to be represented by the Pieniny Klippen Belt (PKB) which is a few kilometres wide and about 600 km long unit between the Outer Western Carpathians (OWC) and Central Western Carpathians (CWC) (Plašienka et al., 1997; Schmid et al., 2008). Unlike the Neotethian suture in the Western Carpathians, the PKB does not show the typical characteristics of a suture. The PKB is a sub-vertical unit with mainly shallow marine limestone and flysch deposits in a conspicuous “blockin-matrix” structure (Plašienka et al., 1997). The presence of “exotic” sediments in the PKB and the southernmost units of the OWC along with their shallow marine deposition environment led to the theory proposing the presence of a continental sliver called the Czorsztyn Ridge in the Alpine Tethys, dividing it into two oceanic/marine basins: the Magura Ocean to the north and the Vahic Ocean to the south (Plašienka, 2018). This controversial continental fragment possibly forming the basement for PKB successions, and its structural relationship with the adjoining OWC and CWC units, make it the main target of this project. The objective is to find evidence of the presence of this continental block, the Czorsztyn Ridge, which may have subducted along with the Vahic oceanic lithosphere underneath the CWC (Schmid et al., 2008). A passive seismic experiment will provide insight into the deep lithospheric structure across the PKP, testing the presence of a tectonic suture along with relaminated remnants of the Czorsztyn Ridge, and potential remnants of subducted or underthrusted lithosphere. Eighteen broadband stations have been deployed in a ~N-S transect (Fig. 1a) under the umbrella of the AdriaArray initiative, cutting across the PKB and Neotethian Meliata suture to the south. The data obtained during up to three years will complement 10 other permanent and temporary broadband stations, forming an approximate 370 km long profile and will be used to perform receiver function analysis and build structural and velocity models of the lithosphere (i.e., Schiffer, 2014; Schiffer et al., 2023) beneath the Western Carpathians. The horizontal extent of the imaging is shown in Figure 1b.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 65--66
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:

Aptian greenhouse climate and icehouse interludes – alpine Tethyan archives revisited

Autorzy:

Weissert, Helmut

Powiązania:

https://bibliotekanauki.pl/articles/24202103.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
climate
Alps

Opis:

In this study we revisit two Cretaceous archives in the Alps, and we test hypotheses of major sea level falls related to ice age interludes in the Aptian. The first of the two successions in focus was formed along the northern margin of the alpine Tethys and is today preserved as Garschella Formation in the Helvetic nappes of Switzerland. Aptian phosphorites of the Luitere Beds containing Deshayites deshayesi and Dufreonia are overlain by up to tens of meters of siliciclastic shales, the Gams Beds. Gams Beds with low carbonate content are poorly dated, according to available biostratigraphies they are of Late Aptian age (nolani ammonite zone). Gams Beds are covered by up to 15 m glauconitic bioclastic sandstones and limestones (Brisi sandstone and limestone). The second locality we have revisited is Zürs in the Northern Calcareous Alps (NCA, Vorarlberg, Austria). There, a condensed succession of Jurassic-Cretaceous age records Southern Tethyan ocean history of a “submarine bank”. Jurassic radiolarian cherts are overlain by pelagic limestones of earliest Cretaceous age followed by an Aptian phosphorite hardground. These phosphorites are covered by an up to several meter thick succession of reworked crinoidal limestones and then by several tens of meters of “Kreideschiefer” (Lech Formation), which are of Albian to Cenomanian in age. Phosphorites at both localities record a time of hardground formation related to changes in Tethyan oceanography, triggered by a major perturbation of the global carbon cycle and by corresponding changes in climate and oceanography. Condensed sedimentation records intense current activity on submarine highs and along the northern Tethyan shelf. Remarkable is the poorly understood change in sedimentation following hardground formation at both locations during Late Aptian time. The Helvetic Gams Beds (Garschella Fm.) record increased shedding of siliciclastics along the northern Tethys, either related to increased weathering or to a drop in sea level. We propose, that an eustatic drop of seal level explains observed northern Tethyan shifts in Late Aptian sedimentation. A corresponding drop in sea level is recorded at other localities as the Oman Mountains, along the Algarve coast in Portugal or in the Basque-Cantabrian Basin. There, most prominent “cold snaps” or “ice age interludes during Aptian greenhouse climate” are dated as martinoides to nolani ammonite zone, they coincide with the deposition of the Gams Beds. Bioclastic limestones in the Helvetic succession and in the NCA record carbonate shedding at a time of renewed sea level rise following a major Aptian sea level drop. The Late Aptian prograding carbonate system of the NCA, considered as the source of crinoidal sands, was positioned along the northern margin of the evolving Eastern Alps while Brisi carbonate sands where shedded from a Northern Tethyan carbonate ramp. The Aptian condensed sediments of Helvetics and of NCA are indicators of extreme shifts in Aptian climate triggered by perturbations of the global carbon cycle. The Aptian-Albian Zürs succession provides additional information on the rapid transition of a passive continental margin with pelagic sediments into an Austroalpine foreland basin represented by “Kreideschiefer”.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 78--78
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:

Reappraisal of the Changning-Menglian Belt as a Suture Zone for the Tethys in Western Yunnan, China: Late Paleozoic faunal and sedimentary evidence

Autorzy:

Huang, Hao
Zeng, Jianbing
Jin, Xiaochi

Powiązania:

https://bibliotekanauki.pl/articles/24202111.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
China
Paleozoic

Opis:

The Changning-Menglian Belt in western Yunnan, China has long been considered a major Tethyan suture in SE Asia, based mainly on fragmented Paleozoic ophiolites, slices of Devonian-Triassic radiolarian cherts and possible seamount limestones of Permo-Carboniferous age (Fig. 1). However, some students also argued for a setting of passive continental margin for this belt and a cryptic suture further east representing the vanished Tethyan Ocean (Ridd, 2015). To evaluate this hypothesis, we have been studying late Paleozoic strata and fusulinids in this belt for years. We recently collected late Carboniferous to Middle Permian fusulinids from various sections in this belt, including ascendingly Triticites assemblage, Sphaeroschwagerina sphaerica assemblage, Eoparafusulina assemblage, Chalaroschwagerina solita assemblage and Neoschwagerina assemblage. Further comparison reveals that the fusulinid taxonomy in this belt still differs from that in S China. For instance, the Early Permian fusulinids in this belt generally lack Pseudoschwagerina, a typical Cathaysian element. Moreover, quantitative analysis (Rarefaction) confirms that the generic diversity in this belt remains lower than in S China. These results supports that a substantial portion of the Permo-Carboniferous limestones in this belt originated from seamounts located far from the northern Gondwana margin, meanwhile slightly south of the equatorial region, also considering the couplet of carbonates and underlying basalts (OIB type). Furthermore, petrographic and geochemical analyses of the Carboniferous siliciclastic Nanduan Formation demonstrate a mature continental provenance and two peaks of detrital zircon ages (ca. 950 Ma and ca. 550 Ma) (Zheng et al., 2019). Notably, these two peaks are also shared by metasedimentary rocks (e.g., the Ximeng and Lancang Groups) widespread in this belt as well as peri-Gondwana blocks. These data suggest that the Paleozoic siliciclastics covering this belt’s eastern and western parts were derived from the Gondwana margin. Therefore, significant siliciclastic inputs from the Gondwana margin over much of this belt contradict the implied vast Paleozoic ocean in this belt. In contrast, the siliciclastic Nanpihe Group (Devonian-early Carboniferous) in the central part demonstrates a detritus source from continental arcs and clusters of detrital zircon ages of ca. 435 Ma and ca. 950 Ma, which correlates well to Silurian magmatism in the Simao and S China blocks. In conclusion, we propose that the Changning-Menglian Belt was part of the passive continental margin on the eastern flank of the Baoshan-Shan Block during the late Paleozoic, while and tectonostratigraphic slices of seamount limestones, Nanpihe Formation or even ophiolites are allochthonous and were displaced to their present position during the Late Triassic closure of the Tethys.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 27--28
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:

Rifting and closure of two branches of the Tethys; from Neotethys to Alpine Tethys

Autorzy:

Fodor, Laszlo

Powiązania:

https://bibliotekanauki.pl/articles/24202112.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Neotethys
rifting

Opis:

The western termination of the Neotethys is marked by a complex interaction of several small oceanic basins which were formed and closed progressively. The western end of the Neotethys was opened from Permian to Middle Triassic; spreading started from Anisian. The rifting was associated with acidic, sometimes basic magmatism; Permian intrusions are widespear in certain zones (Eastern Alps), and together with Middle Triassic volcanites, played a role in weakening of the extending continental lithosphere. The rifting process was interacting with evaporite tectonism in regions where Late Permian evaporites were formed potentially as a post-rift or intra-rift stage. Due to loading of the ovelying Early Triassic clastic-carbonate ramp sequence, and the still ongoing extensional deformation, and/ or gravitational sliding of shelf domains toward deepening extended continental margin, salt tectonics probably started in latest Early Triassic. The uprising salt walls strongly influenced shelf and eventually slope deposition; the minibasins between salt walls often hosted carbonate ramp or platform development while collapsing salt structures could turn to deep “intra-platform” basins. The salt tectonics controlled the continuing facies differentiation during the Late Triassic. The development of salt-cored normal faults are not characteristic for a typical post-rift passive margin, but due to their relation to underlying salt, facies differentiation was maintained. The earliest sign of rifting of the Alpine Tethys can be seen in the Late Triassic deep grabens (Southern Alps, southern Transdanubian Range). This is the reason that separation of salt-related deformation, and crustal extension is not evident in some zones. The closure of the Neotethys started with intra-oceanic subduction, probably with a double polarity, and the formation of a supra-subductional new oceanic lithosphere (the Vardar zone in some interpretations). The age of this process is somewhat controversial in different models. Isotopic ages of metamorphic sole of the Vardar ophiolites suggest 175–170 Ma while neutral to acidic differentiates in the eastern Vardar testify ongoing Late Jurassic oceanic magmatism (~155–155 Ma). A complex system of melange was formed under and in front of the emplacing upper plate Vardar ophiolite. While sub-ophiolitic melange with serpentinitic matrix formed below the overlying hot oceanic lithosphere, the sediment-hosted melange contains blocks from different zones of the passive margin and partly the overlying ophiolite. Stratigraphic ages indicate that this processes happend during the Middle and Late Jurassic. The obduction happened in latest Jurassic (Tithonian) indicated by reef limestone on top of ophiolites. This was followed by the imbrication of the underlying passive margine Adriatic continental lithospere during the entire Cretaceous and Cenozoic. Clastic foreland basins were formed within this lower plate supplied partly by the passive upper plate ophiolite. The Alpine Tethys went on intensive rifting which ended with break-up in late Middle or in the Late Jurassic on its southern Piemont-Ligurian branch. The onset of subduction is not exactly clear but could happen in the Late Cretaceous resulted in high-pressure metamorphism of the oceanic domains in the Eocene (Tauern window). The Transdanubian Range of Hungary was situated between the two oceanic domains during the whole Mesozoic. While this unit has not been buried and only deformed modestly, the sedimentary events reflect the complex evolution. Middle Triassic rifting resulted in disruption of Early Triassic mixed siliciclastic-carbonate ramp into platform and somewhat deeper grabens. Small-scale synsedimentary faults and neptunian dykes testify this phase. Away from the break-up zone, the area underwent important post-rift subsidence compensated by platform carbonate sedimentation through the Late Triassic. However, the trace of initial Late Triassic rifting is present in forms of synsedimentary faults in the western side, closer to the future Neotethys. Following the earliest Jurassic decline of platform biota, the ongoing Alpine rifting disintegrated the entire TR carbonate platform into shallower, sediment free ridges and somewhat deeper grabens. This rifting and subsidence resulted in deposition of pelagic red nodular limestone in the Aalenian-Bajocian. After cherty sedimentation in the Callovian–Oxfordian, very modest extension appeared in the latest Jurassic. Although this phase could be considered as the final extension of the Alpine Tethys rifting far to the west, it is more probable that in fact this is due to slight downbending of the TR below the distal ophiolite emplacement to the east. The Neotethyan influence prevaild in the eastern TR during the Early Cretaceous. A clastic foreland basin was supplied by ophiolite and supra-ophiolite detritus of the obducted Neotethyan Vardar unit. Structural cituation changed in the late Early Cretacoues, around 115 Ma (Albian). The entire TR underwent shortening. The unit, formerly the lower plate of the Neotethyan system, was emplaced, as the highest nappe, on to the other continental units of the Austroalpine system. Within the Eastern Alps, this was associated with intracontinental subduction initiated in zone of Permian magmatism having thermally weakened the lithosphere. The relationship of this subduction, and associated high to ultrahigh pressure metamorphism is not clear, but eventually could have connected to large-scale displacement of the Neotethyan subduction zone at its northernmost termination zone. The complete change of the TR, from lowermost position to upper plate, is the reflection of complex 3D geometry of overlapping oceanic domains and could happen in other Tethyan areas

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 19--20
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:

Tectono-sedimentary evolution of the junction area between the Western and Eastern Carpathian nappe systems (Ukrainian Carpathians)

Autorzy:

Hnylko, Oleh

Powiązania:

https://bibliotekanauki.pl/articles/24202114.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Carpathians
Ukraine
Tethys

Opis:

The Carpathians contain the remains of the Western Tethys, the main of which are: continental/microcontinental fragments (Alkapa and Tisza-Dacia terranes) of the Tethys Ocean, now located in the Central (Inner) Carpathians, and (palaeo)accretionary prisms, building mainly the Outer Carpathians. The Ukrainian Carpathians occupy the junction where the Western Carpathian and Eastern Carpathian nappe systems converged. In the presented work, author try to reconstruct the tectono-sedimentary evolution of the Eastern and Western Carpathian nappe systems in the junction area on the basis of own and published geomapping works, stratigraphic, sedimentological and structural research using existing restorations (see van Hinsbergen et al., 2020 and references therein). The Central Western Carpathian nappes (part of the Alcapa Terrane) are not exposed in Ukraine and probably buried under Neogene Transcarpathian Depression. The Central Eastern Carpathian nappes (part of the Tisza-Dacia Terraine) are represented in Ukraine by the Marmarosh thick-skinned basement nappes, that were formed in the Early Cretaceous time and overlapped by the latest Early Cretaceous–Paleogene post-nappe sedimentary cover. Between the Central Eastern and Central Western Carpathian nappe systems, the Pieniny Klippen Belt suture zone and Monastyrets Nappe filled with Paleogene flysch are developed. The structure of the junction between the Outer Eastern and Outer Western Carpathian nappe systems is more complicated. In Ukraine, the Outer Carpathians are made up of a several stacked nappes filled with Cretaceous–Neogene, mainly flysch sediments uprooted from their original substratum. In the Eastern Carpathian segment of Tethys at the Late Jurassic and/or Early Cretaceous, Ceahlau-Severin ocean (called Fore-Marmarosh one in Ukraine) was opened between the Dacia continental block (part of the Tisza-Dacia Terrane) and the Eurasian continent (van Hinsbergen et al., 2020 and references therein), that suggested by rift oceanic and continental basalts occurring under the Cretaceous flysch of the Outer Eastern Carpathian. Sinking of the Dacia (micro)continent into a subduction zone existed in the Neotethys ocean and inclined to the west (van Hinsbergen et al., 2020), could have caused the east-directed thrusting of the thick-skinned Marmarosh Nappes towards the CeahlauSeverin ocean. Ahead the Marmarosh nappe pile, the Eastern Carpathian Internal flysch thin-skinned nappes such as the Kamyanyi Potik, Rahiv, Burkut, Krasnoshora, Svydovets and Chornohora ones were formed. Coarsening upward and regular younging of the stratigraphic successions from inner to outer nappes suggest their attribution to the accretionary wedge growed in the Early Cretaceous–Paleogene time due to the subduction of the Outer Carpathian flysch basin basement under the Marmarosh pile. In the Western Carpathian segment, the Pieniny Klippen Belt accretionary wedge began to rise in the Late Cretaceous due to subduction of the Penninic oceanic domain under the Central Western Carpathians (part of the Alcapa Terrane) accompanied by detaching and grouping together originally very distant lithofacies (Plašienka, 2018 and references therein). The Western Carpathian Internal flysch nappes such as the Magura and Dukla units were attached to the Fore-Alcapa prism during the Middle Eocene–Oligocene, accordantly to outward shifting and uplifting of the trench-like Magura and Krosno lithofacies during this time. Closuring of the Monastyrets “between-terrainian” flysch basin at the late Eocene suggests the collision of the Alcapa and Tisza–Dacia terranes at the turn the Eocene and Oligocene. As a result, the Fore-Alcapa and Fore-Tisza-Dacia wedges were incorporated within an amalgamated internal wedge system that limited from the SW the Outer Carpathian basin. This unificated Menilite–Krosno basin was gradually uplifted and its deposits were subsequently thrusted as the external Silesian, Skyba and Boryslav-Pokyttya nappes onto the Miocene Carpathian Foredeep. Sedimentological and structural data suggest northeastward shift/migration of the wedge front–trench/foredeep– forebulge during Carpathian evolution. In addition, the junction of the Eastern and Western Carpathian accretionary wedges is complicated by strike-sleep movements.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 25--26
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:

Palaeogeographic perturbations in the key-area between the Alpine Tethys and the Neotethys Realms during the time of tectonic overturns: Jurassic of the Alpine-Dinaric transition zone

Autorzy:

Rožič, Boštjan

Powiązania:

https://bibliotekanauki.pl/articles/24202118.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Alpine
palaeogeography

Opis:

The major Mesozoic palaeogeographic disintegration of the present-day transitional area between the Alps and the Dinarides (Slovenia) occurred due to the Middle Triassic rifting event related with the opening of the Neotethys Ocean. By the Norian, three major palaeogeographic units were formed: the Dinaric (Adriatic, Friuli) Carbonate Platform (DCP) in the south, intermediate, E-W extending Slovenian Basin (SB) and the Julian Carbonate Platform (JCP) in the north. The platforms were characterized by a Dachstein type platform, while the basin was filled with hemiplegic and resedimented limestones, most of which are now dolomitized. To the west, there was a shallow water “bridge” between the two platforms. After the Triassic-Jurassic Boundary crisis, the palaeogeographic setting was preserved, but the margins of the platforms turned into ooidal factories. During the Early Jurassic, SB was almost exclusively filled with ooid calciturbidites from the north, which can be explained by the wind/leeward position of the basin with respect to the particular platform. The first rifting phase of the opening Alpine Tethys, generally dated to the earliest Jurassic, is poorly expressed in this area. The main products are limestone breccias that occur in the western part of the SB. In contrast, the second rifting phase (dated to the Pliensbachian in Slovenia) completely disintegrated JCP. The margins subsided first and were characterized by open shelf conditions with crinoid meadows, while the inner parts of the JCP remained shallow-marine. In the SB, the initial subsidence can be seen in the altered composition of the calciturbidites. Namely, the ooid/peloid dominated resediments changed to crinoid/ lithoclast dominated. In the Toarcian, sedimentation ended on most of the JCP, with only sporadic marls occurring at the margins. At the same time, the sedimentary environment of the DCP also deepened and nodular or crinoid limestone was deposited. The SB is characterized by uniform clay-rich sediments that vary greatly in thickness, indicative of differential subsidence caused by the second rifting phase. In the Middle Jurassic, shallow-water sedimentation re-established on the DCP, the margin being characterized again by ooidal shoals, the sedimentation of the SB gradually changed to siliceous limestone, while the JCP and the “bridge” between the JCP and DCP are characterized by non-sedimentation. The last important Jurassic change occurred during the Bajocian-Bathonian stages. Condensed Ammonitico Rosso-type limestone began to be deposited on the “bridge” and the JCP, while sedimentation in the SB changed to pure radiolarite. In the past, this was interpreted as a result of thermal subsidence associated with oceanization of the Alpine Tethys. However, studies in the last decade suggest a more complex tectonic evolution. Because the area in question lies between the opening Alpine Tethys to the west and the concurrent onset of subduction of the Neotethys to the east, it has been subject to strong differential subsidence between the largescale DCP and all units north of it. The exact nature of the tectonic deformation is not yet clear, but a transtensional regime is most probable. These events resulted in the disintegration and collapse of the northern DCP margin, as evidenced by the sedimentation of limestone breccia megabeds along the entire SB southern margin. These megabeds not only indicate enhanced tectonics, but also provide important information about the pre-Middle Jurassic architecture of the DCP margin, which is no longer preserved. They consist of very diverse limestone lithoclasts and an ooid packstone matrix. Analysis of the clasts revealed that the Late Triassic DCP margin was characterized by Dachstein-type reefs and the Early Jurassic by ooid shoals. In the interior of SB, these strata merge into ooid calciturbidites interlayered between radiolarite and become completely wedged in the northern part of the basin. Corresponding gravity-flow deposits also sedimented on the subsided “bridge” between the DCP and the JCP, and even on the northern margin of the DCP itself. An important difference is the simpler composition of the resediments in this area. Namely, they consist entirely of Middle Jurassic platform margin and slope lithoclasts. This is explained by the less pronounced palaeotopography between the active platform and submerged “bridge”, which did not allow erosion of the older platform limestone (as observed in SB). The described collapse of the DCP margin caused it to retreat, and marginal reefs formed over the underlying inner platform limestones in the Late Jurassic. The emersion phase in the Kimmeridgian ended reef growth and the margin turned back into ooid rich shoals. At the same time, the SB was characterized by continuous radiolarite sedimentation and drowned JCP together with the “bridge” with the Ammonitico rosso facies, characterized by several stratigraphic gaps. Rare calciturbidites are interbedded in areas near the DCP (southern SB and a drowned “bridge”). At the end of Jurassic, all areas north of the DCP show uniform sedimentation of the Biancone Limestone Formation.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 60--61
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:

Early Triassic conodonts in Western Tethys

Autorzy:

Kolar-Jurkovšek, Tea

Powiązania:

https://bibliotekanauki.pl/articles/24202124.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Triassic
biostratigraphy

Opis:

Conodonts are phosphatic, tooth-like elements of extinct jawless vertebrates that are classified in the independent class Conodonta. Due to their rapid evolution, wide palaeogeographic distribution and high resistance, conodonts are one of the most significant microfossil groups in the biostratigraphy of the Paleozoic and Triassic. Animals with conodonts were bilaterally symmetrical, exclusively marine organisms, where they inhabited a variety of habitats. These include both open sea habitats, whereas some species adapted to shallow habitats of epicontinental seas. For this reason, conodonts are extremely important for understanding of the palaeoecological and palaeogeographic conditions of the Paleozoic and Triassic. They were unquestionably one of the most successful animal groups, since they existed more than 300 million years and their elements are widely used as index fossils. Conodonts have shown their value for Triassic biostratigraphy. Based on international criteria the Permian-Triassic system boundary is defined with the first appearance of the conodont species Hindeodus parvus (Kozur & Pjatakova). The Permian-Triassic interval strata of the GSSP section in Meishan (China) are next to the platform-bearing gondolellids marked by the presence of Hindeodus-Isarcicella population that enabled to introduce also a conodont zonation for shallow facies. A standard conodont zonation is, except for the two lowermost Triassic zones, based on gondolellid genera that lived in deeper water: Clarkina, Sweetospathodus, Neospathodus, Novispathodus, Borinella, Scythogondolella, Icriospathodus, Triassospathodus and Chiosella. Certain Dienerian and Smithian strata of Western Tethys are marked by shallow water and euryhaline genera and due to the absence of global biozonation markers, a stratigraphic value of some genera (Hadrodontina, Pachycladina, Eurygnathodus, Foliella, Platyvillosus) is recognized. These shallow water genera were ecologically controlled (temperature, oxygen levels) that have been adapted to the epicontinental ramp environment and were particulary instrumental in forming the western part of the Tethyan province.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 36--36
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:

Evolution of the Western Tethys as seen from the Western Carpathians’ perspective

Autorzy:

Plašienka, Dušan

Powiązania:

https://bibliotekanauki.pl/articles/24202134.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Carpathians
evolution

Opis:

The palaeogeographic positions of the pre-Cretaceous Tethys “western ends” (Kovács, 1992) and their relationships to easterly located oceanic domains remain to belong to the most challenging issues in deciphering the structure and tectonic evolution of the European Alpides (e.g. Schmid et al., 2020). Due to the westward increasing paucity of direct indications of ancient oceanic domains and their discontinuous occurrences, a number of sometimes considerably different reconstructions have been proposed by several authors. All these are based on various data and authors’ preferences; therefore achievement of a widely accepted model seems not to be probable at present. In general, searching for evidences of former oceanic domains in the nappe edifice of collisional mountain belts, commonly in the suture zones, is based on several fundamental criteria: 1) ophiolite slivers and ophiolite-bearing mélanges as vestiges of consumed oceanic lithosphere; 2) blueschistto eclogite-facies metamorphosed units recording the subduction/exhumation processes within a subduction channel and/ or accretionary prism; 3) deep-marine synorogenic sedimentary complexes like wildflysch or olistostromes; 4) mixture of these in chaotic units within an accretionary wedge; and 5) a specific case of intraoceanic subduction resulting in ophiolite obduction, but this is not considered as a continental collisional tectonic setting. Indirectly, position of past oceanic basins can be detected by: a) secondary occurrences of an oceanic crust-derived detritus, including the heavy mineral spectra, in syn- to early post-orogenic sedimentary clastic formations and clues to their source areas; b) shelf-slope-continental rise facies polarity of former passive margins; c) progradational trend of collisional thrust stacking of the lower plate with a suture (often totally destroyed) in the uppermost structural position in the rear part of an orogenic pro-wedge; d) subduction-related calc-alkaline magmatism accompanying the active margin; e) upper plate back-arc extension, or retro-wedge thrusting opposite to the pro-wedge in a bivergent orogen with the suture in its axial zone; f) major crustal-scale discontinuities revealed by deep seismic sounding connected to surface fault zones separating palaeogeographically distinct domains indicating possible plate boundaries. All these potential clues have been considered while reconstructing the Mesozoic tectonic evolution of the Western Carpathians (Plašienka, 2018 and references therein). It should be noted that no single criterion characterized above, even not a few indirect signs are enough to define a particular orogenic zone or unit as an evidence for an oceanic suture. There is only one Western Carpathian zone which fulfils most of them. It is represented by units and rock complexes grouped in a tectonic superunit known as the Meliaticum and respective oceanic realm as the Meliata Ocean. The Meliata-related units bear clear signs of criteria 1, 2, 3, 4 and indirect indicators a, b, c and e. Whatever different are the interpretations of the Meliata Ocean origin (e.g. born as a back-arc basin initiated by the northward subduction of Palaeotethys, or simply as a northern margin or embayment of Neotethys), or even its existence as an independent domain (regarded as a facies zone only), all palaeotectonic interpretations of the Alpine tectonic evolution of the Western Carpathians have to take into account these pieces of evidence.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 57--57
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 11.

Tytuł:

Geochemistry of the Triassic–Jurassic lateritic bauxites of the Salt Range: implications for eastward extension of the Tethyan bauxite deposits into Pakistan

Autorzy:

Iqbal, Saqib
Bibi, Mehwish
Wagreich, Michael

Powiązania:

https://bibliotekanauki.pl/articles/24202138.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Pakistan
geochemistry
Tethys

Opis:

Bauxite deposits are residuals of intense lateritic weathering under warm and humid palaeoclimates. The Triassic– Jurassic Boundary (TJB) interval in the Salt Range, Pakistan, provides one such case of bauxite deposits formation along the SW tropical Neo-Tethyan passive margin. Thick, red bauxites/bauxitic clays occur at the contact of the Upper Triassic Kingriali Formation and the Lower Jurassic Datta Formation. These bauxites are rich in kaolinite, haematite, boehmite (Al2O3 and Fe2O3), and are depleted in silica (SiO2). Geochemical proxies of the succession signal intense chemical weathering of the parent siliciclastics under Mesozoic “greenhouse” conditions. Certain trace elements and Rare Earth Elements (REEs) are enriched up to seven times compared to mean Upper Continental Crust (UCC) values. These bauxites are synchronous with the Amir-Abad bauxites of the Alborz Mountains, central Iranian Plateau, that occur between the thick Triassic dolomite/dolomitic limestones of the Elika Formation and the Lower Jurassic Shemshak Formation. Thus, the Salt Range, Pakistan, provides evidence for the eastward extension of the Irano-Himalayan bauxites that are extended westward into Mediterranean bauxites, and the western Tethys by correlation with European bauxites. The TJB bauxites in the Salt Range support increased chemical weathering on the SW Neo-Tethyan passive margin and correspond to an associated sea-level fall during this time interval. This supports the Neo-Tethyan tectonics contribution in the formation of bauxite deposits during the Triassic–Jurassic in addition to the widely studied karst-bauxites that formed in response to the subduction and orogenic processes in the Paleo-Tethys.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 30--30
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:

Sequence stratigraphy of the Upper Cretaceous–Eocene Belqa Group of Jordan (southern Tethys margin)

Autorzy:

Kalifi, Amir
Ardila-Sanchez, Maria
Messaoud, Jihede Hay
Laila, Wesam Abu
Buchem, Frans van
Ibrahim, Khalil
Powell, John

Powiązania:

https://bibliotekanauki.pl/articles/24202139.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
stratigraphy
Jordan

Opis:

The Belqa Group of Jordan (Upper Cretaceous–Eocene) contains a remarkable succession of sedimentary lithofacies, including chalk, sandstone, chert, phosphorite, oyster mounds and organic-rich marls deposited along the passive southern margin of the Neo-Tethys Ocean. The Belqa Group is now outcropping in spectacular wadis where they can be studied in detail. The exceptional outcrops exposures provide unique opportunities for studying three-dimensional spatial facies variations. However, this 3D facies distribution requires robust time control and the combination of modern sequence stratigraphic concepts and high-resolution dating methods. We report the establishment of a regional sequence stratigraphic model that provides the temporal framework for further detailed sedimentological, palaeontological and geochemical studies. Preliminary results show a stratigraphic organization in four major depositional sequences (3rd order), which are broadly in agreement with the lithostratigraphic formations. The age dating is based on new nano-fossil analyses and C/O and Sr isotope stratigraphy. A subdivision into higher-frequency sequences (4th/5th order) significatively improves the resolution of the stratigraphic framework and our understanding of spatio-temporal distribution of the sedimentary facies. The four sequences are: 1) The B1 sequence (Upper Coniacian-Santonian), characterized by a transgressive phase of chalk-rich sedimentation (coccolithophore-dominated) and a regressive phase of a prograding siliciclastics with a distal transition to the first phosphorite-chert facies. 2) The B2 sequence (Lower Campanian) also starts with a transgressive chalk dominated facies and subsequently develops into a chert-dominated marl facies (radiolarian-dominated). The chert is locally associated with thin phosphates and coquinas, as well as organic-matter rich facies in proximal marine settings. 3) The B3 sequence (Upper Campanian) is also characterized by a transgressive chalk dominated facies. The regressive phase is constituted by dm- to m-thick phosphorite beds that were deposited coevally with giant oyster banks (decameter scale). 4) The B4 sequence (Maastrichtian-Paleocene) represents a dramatic facies change to organic-rich pelagic marls, and can probably be further subdivided. This sedimentary succession highlights both gradual and rapid changes in biogenic productivity and geochemistry. These changes are punctuated and partly driven by significant relative sea-level changes, and likely also larger scale palaeoceanographical processes that are the focus of future work.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 32--32
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 13.

Tytuł:

Tracing palaeocurrents from the Arctic Realm into the Tethys Ocean: the use of glendonite as an indicator for cold bottom water masses

Autorzy:

Merkel, Anna
Munnecke, Alex

Powiązania:

https://bibliotekanauki.pl/articles/24202087.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
ocean
water

Opis:

Today, the global conveyor belt of ocean currents is controlled by the configuration of continents and the climate. Conversely, ocean currents influence water and air temperatures as well as the amount of rainfall on a regional to local scale. In addition, they govern species distribution patterns, sedimentation patterns and the dispersal of nutrients in both oceans and epeiric seas. Therefore, the reconstruction of palaeocurrents is crucial for the understanding of ancient environments and the past climate. An important driver for the global ocean circulation is the formation of deep water. However, deep-water production is difficult to estimate, and its circulation is difficult to reconstruct, not only today but especially in the geological record. Palaeocurrent reconstructions are often based on the temporal and spatial distribution of marine species. In this presentation, a new approach is proposed which uses the occurrence of glendonites as a proxy for cool bottom currents. Glendonites are pseudomorphs after the hydrous carbonate mineral ikaite (CaCO3·6H2O) which only forms in environments characterised by near-freezing temperatures. Throughout the Phanerozoic, glendonites can be found in successions which were deposited in high latitudes. However, examples of glendonite occurrences in mid-latitudinal sections are also reported. One of these examples are upper Pliensbachian (Lower Jurassic) glendonites from a shallow-marine succession in South Germany which was located in the European epicontinental sea  – an area, where it was technically too warm to form the precursor mineral ikaite. Based on petrographical and sedimentological investigations as well as stable isotope analyses it is concluded that a low temperature was the main factor for ikaite formation in the studied section. To explain the low water temperatures, a model for a thermohaline circulation in the European epicontinental sea is proposed. The cool climate in the late Pliensbachian initiated the growth of sea ice in high latitudes, leading to the formation of cold and saline bottom waters analogous to the modern formation of North Atlantic Deep Water (NADW) and Antarctic Bottom Water (AABW). The cold bottom current flowed southward from the Arctic Realm through the Viking Corridor into the European Epicontinental Sea, thereby causing a massive cooling of the deeper parts of the epeiric sea, which led to the formation of ikaite in temperate areas. After passing the shelf, the bottom current entered the Western Tethys, probably forming a deep water mass. The proposed model can help to explain mid-latitudinal glendonite occurrences not only in the Pliensbachian, but also in other areas and time slices which are characterised by cooling. Moreover, it enables the use of the pseudomorph as a tracer for cold bottom currents which can be a helpful tool for the reconstruction of global ocean current patterns.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 49--49
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:

A silicified wood from the Early Cretaceous sediments in the Kaligandaki Valley, west central Nepal

Autorzy:

Paudayal, Khum N.
Paudel, Lalu P.
Uhl, Dieter

Powiązania:

https://bibliotekanauki.pl/articles/24202093.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Cretaceous
Nepal

Opis:

A silicified wood has been discovered from the Tethyan Cretaceous (Berriasian) deposits belonging to the Kagbeni Formation of north Central Nepal. The wood exhibits anatomical features which are well in accordance with Araucarioxylon nepalense described by Barale et al. (1976) from another locality in the Kagbeni Formation near Kagbeni in the Thakkhola Valley in Central Nepal. It is a pycnoxylic wood with mostly uniseriate and rarely biseriate bordered pits on radial tracheid walls. According to recent taxonomic opinions this type of wood should not be treated as Araucarioxylon, but as Agathoxylon Hartig. Thus we propose the name Agathoxylon nepalense comb. nov. for this type of wood. The sandstones of the Kagbeni Formation have been interpreted as delta-deposits, with a major flow direction from the south. This suggests that the wood originated from the northern margin of Indian sub-continent.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 55--55
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 15.

Tytuł:

Larger Benthic Foraminifera from Paleocene–Eocene carbonates, Eastern Tethys, Meghalaya NE India – their comparison with Western Tethys and palaeobiogeographical significance

Autorzy:

Tewari, Vinod Chandra

Powiązania:

https://bibliotekanauki.pl/articles/24202096.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
India
Himalaya

Opis:

India–Asia plate collision and uplift of the Himalaya took place during Paleocene–Eocene time (50 Ma). The extension of western Tethys Sea from Europe to Asian eastern Tethyan region has been correlated by assemblages of Larger Benthic Foraminifera (LBF). Global correlation and paleobiogeography of the eastern Meghalayan and western Tethyan Sea is discussed on the basis of SBZ of Paleocene– Eocene foraminifera assemblages (Fig. 1). Paleocene–Eocene Lakadong Limestone and Umlatodoh Limestone were deposited in shallow marine carbonate ramp depositional environment in Shillong Plateau, Meghalaya, NE India. The sedimentation basin is part of the Eastern Tethys and LBF and calcareous algae is the major carbonate facies. Coral reefs are not developed in these carbonates in contrast with the western Tethys limestones in Adriatic Platform and western European –Alpine region (Tewari et al., 2007).The LBF and algal assemblage in both the limestones is consistent with other parts of Eastern Tethys in Eastern India and Tibet (Hottinger, 1971; Scheibner & Speijer, 2008, Tewari et al., 2010). The latest Paleocene (Biozone SBZ4) miscellanids and ranikothalids are replaced by Early Eocene alveolinids and nummulitids, which dominates LBF assemblages in the western Tethyan realm at the P-E boundary (Scheibner & Speijer, 2008), Thanetian (SBZ4 Biozone) is equivalent to Tethyan platform stage II (Scheibner & Speijer, 2008). In standard biozones Ilerdian (SBZ5-SBZ6), a general reorganization in LBF communities is recorded with a long life and low reproductive potential (Hottinger, 1971). However, in the Meghalayan LBF assemblages of the lowest Eocene (biozones SBZ5/6) are still dominated by Ranikothalia and Miscellanea, while new LBFs that first emerged within this time interval elsewhere (e.g. Assilina, Alveolina and Discocyclina) are less important and Nummulites are absent. Later, in the Early Eocene there was a gradual diversification of Discocyclina and Assilina species (Fig. 1), while Ranikothalia disappeared and Miscellanea became less important by the end of the SBZ5/6 biozones. Similar LBF assemblages have been recorded in other parts of east Tethys in western India and Tibet (Scheibner & Speijer 2008; Tewari et al., 2010 and references therein). Such LBF assemblages in east Tethys thus differ from west Tethys. Palaeobiogeographical barriers must have existed between India and Eurasia during early collision of Indian Plate with Eurasia Plate around 50 Ma (Tewari et al., 2010 and references therein). These barriers prevented migration of certain LBF species of Nummulites and Alveolina between these two palaeogeographic regions. LBF dominated facies in the other basins of Meghalaya like Umlatodoh Limestone are well developed in low latitude. However, mixed coral-algal reefs and LBF facies were sparse in low-mid latitude carbonate environments (Adriatic Platform of Italy-Slovenia, Oman, Egypt, Libya, NW Somalia; Tewari et al., 2007, 2010; Scheibner & Speijer, 2008 and references therin). In contrast to west Tethys, corals are absent in Eastern Tethys (calcareous algae is present in SBZ3 and SBZ4 Biozone, Fig. 1) in the Meghalaya and other low-latitude eastern Tethys (Scheibner & Speijer, 2008). Carbonate ramp (shallow tidal flat ) carbonate environments were dominated by LBFs from Early to Late Paleocene (SBZ4, SBZ5, biozones; Fig. 1). It is interpreted that the collision of the Indian and Asian plates must have generated this difference in palaeobiodiversity by creating barriers, which prevented migration of certain LBFs (Nummulites) from west to east. Later, in the Early Eocene (SBZ6, SBZ7-SBZ8 biozones), recorded from younger Umlatodoh Limestone in the upper part gradually replaced by LBF dominated facies in the east, with highly diversified LBF species of Nummulites, Discocyclina, Discocylina jauhrii etc.), indicating stable shallow marine environmental conditions. Stable carbon and oxygen isotope analyses from Paleocene–Eocene Lakadong Limestone and Umlatodoh Limestone strongly supports a shallow marine carbonate platform deposition in Eastern Shallow Tethys, Meghalaya, India (Tewari et al., 2010)

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 71--72
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 16.

Tytuł:

The evidence of Palaeotropics and the Gondwana-derived terrane: an alternative scenario of the Palaeotethys divide in SE Asia

Autorzy:

Udchachon, Mongkol
Burrett, Clive
Thassanapak, Hathaithip

Powiązania:

https://bibliotekanauki.pl/articles/24202101.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Thailand
Tethys
limestones

Opis:

Along the Northern part of the West Thailand Region (NWTR), a long-lasting belt of radiolarian cherts, separates Pennsylvanian to Permian palaeotropical limestones of the Inthanon Zone to the east from Permian limestones in the west containing a temperate marine fauna in the Roadian and a biogeographically distinctive fusulinid fauna in the Wordian. Highly abundant but low diversity of Kungurian radiolarians in silicified shales as well as temperate faunas in limestones from the south and the west of Thailand, respectively support constrains in the temperate environment during the period of deglaciation in peri-Gondawana. The well-known underlying diamictite and overlying temperate sediments with the succeeding fully tropical limestone sequences support a gradational palaeoclimate transition. Devonian faunas found in condensed sequences of the NWTR were deposited in a deep platform or ramp environment. A lack of basalts in the NWTR does not suggest oceanic environments for any Palaeozoic sequence within the NWTR and a paucity of basalts in the northwestern part of the Inthanon Zone also does not provide good evidence of an oceanic realm. Indeed, ‘continental margin’ Carboniferous sandstones appear to underlie the palaeotropical limestones and their plant fossils and their benthonic faunas do not suggest oceanic conditions in the northwestern Inthanon Zone. We, therefore, suggest that an autochthonous or para-autochthonous Inthanon Zone origin for these Carboniferous sandstones is more likely than deposition within a subducting Palaeotethyan Ocean. A strong contrast between the ‘temperate’ Permian limestones of the NWTR and the tropical limestones of the Inthanon Zone further emphasises the Mae Yuam/Mae Sariang Fault Zone (MYMS FZ) as a reactivated oceanic boundary between Gondwana and ‘Cathaysia’ and is supported by the oceanic lithosphere origin of the detrital Cr spinels in the Triassic foreland basin siliciclastics of the NWTR. The limestones of the Inthanon Zone range from Visean to Permian and possibly Triassic and were deposited in shallow, tropical seas for over 90 million years. This longevity is either not possible or highly unlikely for shallow marine carbonates on volcanic seamounts supported on subducting (and therefore cooling and sinking) ocean crust (Huppert et al., 2020) but is possible on isolated carbonate platforms on continental crust separated by narrow basins with limited volcanism. Carboniferous sandstones and Devonian-Permian radiolarian cherts from the Inthanon Zone are continental marginal and are neither pelagic nor oceanic and are interpreted as deposited in extensional, deeper basins between the isolated carbonate platforms. We suggest an alternative hypothesis to the overthrust/ allochthon model where the NWTR is the eastern platform margin of the Sibumasu Terrane from the Devonian through to the Triassic and separated from the Inthanon Terrane by an ocean in the position of the MYMS FZ. It is suggested that Inthanon rifted from Gondwana in the Early Devonian and the NWTR, as part of the Sibumasu Terrane, rifted off in the early Permian. As the Inthanon Terrane ribbon continent drifted northwards the continental crust thinned and extended and small rift basins allowed basalts to be extruded associated with deep-water, continental margin, hemipelagic, non-hydrothermal radiolarian oozes. Isolated carbonate platforms were established on Carboniferous sandstone bases and were separated by deep-water but non-pelagic extensional basins. Turbidites originating on the carbonate highs supplied carbonates clasts containing Devonian through Permian conodonts, to the adjacent basins (Udchachon et al., 2018). We provisionally suggest that the Sukhothai Terrane rifted with Inthanon with its older siliciclastic successions of the Siluro-Devonian (?) Khao Kieo Formation and the unconformably overlying Carboniferous (Dan Lan Hoi Group) (Bunopas, 1982; Ueno & Charoentitirat, 2011) supplying siliciclastic and volcaniclastic debris to the Inthanon Zone. This hypothesis is broadly in accord with Dew et al.’s (2018) ‘explanation A’ for the crustal geochemistry of the northern Thailand terranes. In the early Permian (Kungurian) Sibumasu was probably in cool to temperate seas but by the middle Permian, the NWTR had rifted from Gondwana and was in the southern hemisphere tropics (13° ±2° S, Zhao et al., 2020). Terrane collision occurred during the Triassic (Ishida et al., 2006; Mitchell et al., 2012; Cai et al., 2017; Hara et al., 2021) with the establishment of a thrust front along the Mae Sariang Thrust Zone and the deposition of the mainly siliciclastic Mae Sariang Group on the NWTR within a foreland basin.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 73--74
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 17.

Tytuł:

Jurassic and Cretaceous evolution of Tethys: Palaeoceanographic events

Autorzy:

Yilmaz, İsmail Ömer

Powiązania:

https://bibliotekanauki.pl/articles/24202104.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Cretaceous
Jurassic

Opis:

Jurassic and Cretaceous evolution of Tethys Ocean is characterized by extension of oceans basins, rifting, development of carbonate platforms and sea level fluctuations. Ocean basins and platform margins were sides of records of collaboration of oceanic, sea level and climate changes in different scales. Deposition of organic sediment increased on the margins of the ocean basins at certain time intervals due to changes in oceanic circulation and chemistry, productivity, climate and sea level. Oceanic Anoxic Events (OAE) stated to took place at aperiodic time intervals and generally associated with organic matter deposits and anoxic water columns. Records of oceanic anoxic event can also be associated by potential source rocks in Jurassic and Cretaceous along Tethys Ocean basins and can be tracked by stable isotope shifts, turnover of fossil groups, presence of black shales/organic rich mudstones, change in redox sensitive elements. Volcanic contribution in oceans is also considered as one of the collaborators of OAE generations. OAE records in Jurassic is seen in Toarcian interval and stated as Toarcian OAE. In Cretaceous, OAE records can be stated as Weissert, Faraoni, Selli (OAE1a), Noir, Fallot, Jacop, Kilian, Paquier (OAE1b), Leenhardt, Amadeus (OAE1c), Breistroffer (OAE1d), Bonarelli (OAE2), and OAE3. Generally, Cretaceous OAE are globally correlated or at least hemispherical. Some of them can be weakly correlated due to different duration and magnitude. Stratigraphic positions of OAE can also be used better marker levels in sequence stratigraphic interpretations. Therefore, positions of OAE are very important in terms of higher resolution for platform to basin correlations and even basin to basin. Cretaceous Oceanic Anoxic Events in eastern Tethys Ocean in Pontides and Taurides can be seen in Cretaceous successions (Mid-Barremian, Aptian, Albian, Cenomanian-Turonian) of Central Pontides (NW Turkey) and Central Taurides (S Turkey) (Yilmaz et al., 2004, 2010, 2012) as presence of black shales. The Mid-Barremian black shales (MBE) have been recorded within turbidite succession in deep marine setting in central Sakarya zone of Pontides following the drowning of the platform (Yilmaz et al., 2012). 2‰ shifts in carbon isotope curve is recorded in parallel with European basins, but with low TOC value. The Aptian black shales (OAE1a) are recorded in pelagic carbonate slope environments in central and north of Sakarya zone of Pontides and represented by a negative carbon isotope shift with 2‰, and TOC around 2% (Yilmaz et al., 2004; Hu et al., 2012). In Sakarya zone of Pontides, OAE2 is recorded in pelagic slope carbonates with carbon isotope curve more than 1‰ positive shift and >2% TOC. Another OAE2 was recorded in Antalya Nappes of Taurides without carbon isotope curve but TOC > 20% (Yurtsever et al., 2003, Bozcu et al., 2011). OAE1a equivalent in Tauride Carbonate platform can be interpreted as presence of dark colored thick stromatolite bearing platform carbonates transgressivley overlying the karstic sequence boundary. The OAE1a and OAE2 levels recorded in Turkey can easily be correlated with European examples and mainly controlled by sea level and tectonics in largescale and climate and oceanographic changes in small-scale. The most extensive distribution of the OAE records in Turkey belong to OAE1a and OAE2, and display potential for source rocks for hydrocarbon exploration.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 81--81
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 18.

Tytuł:

Mesozoic tectonostratigraphy of the Western Tethys Realm – a review

Autorzy:

Gawlick, Hans-Jürgen

Powiązania:

https://bibliotekanauki.pl/articles/24202113.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

tectonostratigraphy
Tethys
Mesozoic

Opis:

The Mesozoic sedimentary sequences in the Western Tethys Realm are incorporated in different mountain ranges, most of them located in the eastern Mediterranean area (Eastern and Southern Alps; Western, Eastern and Southern Carpathians; Dinarides, Albanides, Hellenides; units in the Pannonian realm: Pelso, Tisza), others are located to the west (e.g. the Apennine and the Betic Cordillera) These mountain ranges were formed since the Jurassic and experienced in parts polyphase mountain building processes and deformation, lasting until today. Therefore, the tectonostratigraphic evolution of the different Wilson cycles are in cases hard to assign to a specific cycle, because the evolution of the different Wilson cycles is overlapping. This resulted in contrasting palaeogeographic reconstructions and controversial regional tectonic interpretations. In general, two different Wilson cycles can be distinguished. The older Wilson cycle reflect the geodynamic history of the Neo-Tethys (Meliata-Hallstatt, Maliac, Vardar, Pindos/Mirdita/Dinaridic oceans in other nomenclature), and the formed orogen is part of the Tethysides with following evolution as documented in the sedimentary record of the wider Adria plate: – A Late Permian to Middle Anisian rift (graben) stadium with sedimentation of siliciclastics and carbonate ramp deposits in an epicontinental sea. – A Middle Anisian to Middle Jurassic passive margin evolution after the late Middle Anisian oceanic break-up: a) The complex Middle to Late Triassic shallow- to deep-water carbonate platform evolution from the inner shelf (platform facies) to the outer shelf (open-marine basinal facies), and b) the Early to Middle Jurassic pelagic platform evolution. – A Middle to Late Jurassic convergent tectonic regime triggered by ophiolite obduction (“active continental margin evolution”) with the interplay of thrusting, trench and trench-like basin formation, mass movements, and the onset and growth of carbonate platforms, followed by latest Jurassic to Early Cretaceous mountain uplift and unroofing. – Final closure of the remaining open part of the NeoTethys (= Vardar Ocean) in Late Cretaceous to Paleogene times. The younger Wilson cycle reflect the geodynamic history of the Alpine Atlantic (Ligurian, Piemont, Pennine, Vah, Alpine Tethys oceans in other nomenclature), and the formed orogen is part of the Alpides with following evolution as documented in the sedimentary record of the wider Adria plate: – An Early Jurassic (Hettangian to Toarcian) rift (graben) stadium with sedimentation of fully marine deposits in areas the rift cross-cut the older proximal Neo-Tethys shelf and siliciclastics and carbonate ramp deposits in areas the rift cross-cut continental domains. – A Middle Jurassic to Late Cretaceous passive margin evolution after the oceanic break-up since the Toarcian with formation of shallow-water platforms in latest Jurassic–earliest Cretaceous times in certain areas, but predominantly with deposition of hemipelagic sedimentary sequences. – ALate Cretaceous to Paleogene convergent tectonic regime triggered by subduction and subsequent continent (wider Adria)  – continent collision (Europe), followed by Neogene mountain uplift and unroofing. In contrast to the fairly well understood Alpine Atlantic Wilson cycle a lot of open questions exist regarding the NeoTethys Wilson cycle. The main focus is therefore the time frame before the “Mid-Cretaceous” mountain building process with the rearrangement of tectonic units, i.e. the Mesozoic plate configuration in the Western Tethys Realm. Due to the fact that the “Mid-Cretaceous” and younger polyphase tectonic motions and block rotations draws a veil over the older Mesozoic plate configuration, several crucial and still topical questions remain, e.g.: 1) How many Triassic-Jurassic oceans existed in the Western Tethyan Realm. Show these oceanic domains different life cycles, i.e. is the opening and the closure of these oceanic domains contemporaneous or differ their age, and where are the suture zones? In general, two main types of contrasting interpretations/models remain: a) Multi-ocean reconstructions with several oceanic domains between continental blocks, and b) One-ocean reconstruction: an allochthonous model which interprets the ophiolites as overthrust ophiolitic nappe stack (or single ophiolite sheet) from the Neo-Tethys to the southeast to east. 2) Were the Southern Alps/Dinarides/Albanides/Hellenides, the Eastern Alps/Western Carpathians plus some Pannonian units (ALCAPA), some units in the Circum-Pannonian realm (e.g., Tisza Unit), and Pelagonia (including Drina-Ivanjica Unit) independent microplates between independent oceanic domains in Triassic-Jurassic times? Or have these units been scattered by polyphase younger tectonic movements modifying an united continental realm (north-western part of Pangaea) of the Triassic European shelf? The Early Jurassic Pangaea break-up resulted, e.g., in the opening of the Central Atlantic Ocean and its eastward continuation, the Alpine Atlantic.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 21--22
1731-0830

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Geotourism / Geoturystyka

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Biblioteka Nauki

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Skocz do pozycji: 19.

Tytuł:

Geological history of the NW Indian Plate Tethyan passive margin in the Salt Range, Pakistan

Autorzy:

Iqbal, Saqib

Powiązania:

https://bibliotekanauki.pl/articles/24202115.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Pakistan
geology

Opis:

The generally east-west trending Salt Range, located in northern Pakistan, is a part of the foreland zone of the Himalayan Fold and Thrust Belt (HFTB). The 5,000–1,000 m thick Precambrian to Pleistocene sedimentary archives of the Salt Range provide an excellent opportunity for the reconstruction of sedimentation style, palaeoclimatic conditions, and tectonic history of the northwestern margin of the Indian Plate. The Precambrian evaporites of the Salt Range Formation are the oldest rocks in the area and represent the westward extension of the Precambrian evaporitic belt that includes the Hormuz Salt Basin (Iran) and Ara Salt (Arabian Plate). A highly weathered igneous body “Khewrite” occurs in the upper part of the formation and can be correlated with the volcanic record during the Ediacaran-Cambrian transition in the Arabian Plate. The clastic-dominated Lower Cambrian succession in the area is directly overlain by the Permian Tobra Formation and with a gentle angular unconformity. The poorly sorted conglomerates of the Tobra Formation indicate deposition during the Permo-Carboniferous glaciation and the irregular distribution of the Tobra and Dandot formations in the area supports their deposition during the syn-rifting phase of the Neo-Tethys opening. The overlying Upper Permian and Mesozoic strata indicate deposition on the northwestern passive margin of the Indian Plate facing the southern margin of the Neo-Tethys. This represents the drift sequence with multiple phases of passive margin rejuvenation during the Mesozoic. The drift sequence is unconformably overlain by the Paleocene Hangu Formation. Karst bauxites mark this contact and hint at exhumation and exposure in the distal part of the underthrusting plate margin. The Hangu Formation grades upward through the Lockhart Limestone into black shales of the Patala Formation supporting deepening and the possible establishment of a trench setting in the area. The presence of thick evaporites of the Bahadar Khel Salt and Jatta Gypsum in the western part of the area (Kohat Plateau) indicates a restricted lagoonal setting during the closure of the Neo-Tethys during the Eocene. The absence of the Oligocene strata hints at the uplift and exhumation of the area during the Himalayan Orogeny. The Neogene strata of the area consist of fluvial-continental detritus and represent molasse sedimentation. Thermal history modelling based on Apatite Fission Tract (AFT) data indicates three major cooling (uplift) episodes separated by two burial phases in the area. The first cooling event (ca. 520 Ma) coincides with the emplacement of the Mansehra Granite just north of the area (ca. 516 Ma) and supports exhumation correlatable with the Pan-African Orogeny. This was followed by the first burial phase (ca. 500–370 Ma) that supports Late Cambrian–Devonian sedimentation in the area. The second cooling event (ca. 300–280 Ma) coincides with the initial rifting and exhumation associated with the Neo-Tethys opening. Therefore, it appears that the Late Cambrian–Devonian strata were deposited in the Salt Range but were subsequently eroded during the exhumation induced by the Neo-Tethys opening during Permo-Carboniferous. This was followed by Neo-Tethyan passive margin deposition throughout the Mesozoic. An additional cooling episode is observable at around ca. 60 Ma and is supported by the presence of karst bauxites at the base of the Hangu Formation. Provenance analysis of the Paleocene strata suggests that detritus for the Hangu Formation was supplied from the south (Indian Plate). The overlying Patala Formation indicates the onset of sediment supply from the north and hence the uplift of the Himalayan Orogen. The overlying Kuldana Formation supports detritus supply only from the north verifying the Neo-Tethys closure by the end of Eocene. Thus the Paleogene strata represent syn-collisional deposition of the Neo-Tethys in the Salt Range. The second burial event (ca. 20–6 Ma) occurred during the Neogene in response to molasse sedimentation in the foreland of the uplifting Himalayan Orogen that was followed by the final cooling and uplift event (ca. 4 Ma) along the Salt Range Thrust. Thus the stratigraphic successions of the Salt Range provide key information regarding the reconstruction of the northwestern Neo-Tethyan margin of the Indian Plate which can help in the understanding of Neo-Tethyan tectonics in regional and global context.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 29--29
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 20.

Tytuł:

Temporal and spatial heterogeneity of the Ailaoshan–Song Ma–Song Chay ophiolitic mélange, and its significance on the evolution of Paleo-Tethys

Autorzy:

Lin, Wei
Liu, Fei
Wang, Ying
Meng, Lingtong
Faure, Michel
Chu, Yang
Nguyen, Vuong Van
Wu, Qinying
We, Wei
Thu, Hoai Luong Thi
Vu, Tich Van

Powiązania:

https://bibliotekanauki.pl/articles/24202127.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
heterogeneity
Vietnam

Opis:

The ophiolite is the direct evidence to restore the oceanic evolution, and it is used to identify the convergence boundary of the plates. Compared with ophiolite, ophiolitic mélange, especially its matrix, contains more information about the evolution of ocean. The evolution of eastern Paleo-Tethys, between the South China and Indochina blocks, recorded the whole process of rifting from Gondwana and their northward migration and convergence. To understand the tectonic implications from matrix of ophiolitic mélange, the Mesozoic Paleo-Tethys Ailaoshan–Song Ma–Song Chay suture zone located in the North Vietnam–Southeast Yunnan region acts as an ideal study area. Based on the structural geology, we reviewed previous zircon U-Pb dating and Lu-Hf isotopic analyses on the detrital zircon from the Ailaoshan–Song Ma–Song Chay ophiolitic mélange. Accordingly, we subdivide the matrix of these ophiolitic mélange into four parts (M1, M2, M3, and M4; Fig. 1). M1 is mainly located in the middle segment of the Ailaoshan–Song Ma belt. It shows age peaks of 440 Ma and 960 Ma with εHf(t) values of −19.6 ~ +10.3. M2 is mainly located in the NW segment of the Ailaoshan–Song Ma belt, showing a dominant age peak of ~260 Ma. Particularly, it has εHf(t) values of −28.9 ~ +8.1. M3 is mainly located in the SE segment of the Ailaoshan–Song Ma belt, showing the peaks at ~250 Ma, 440 Ma, and 960 Ma with εHf(t) values of −21.9 ~ +10.1. M4 is mainly located in the Song Chay belt, showing the peaks at ~310 Ma, 470 Ma, 610 Ma, 770 Ma, and 965 Ma with εHf(t) values of −28.2 ~ +10.8. The geochronological data of the detrital zircon from the matrix of the Ailaoshan– Song Ma–Song Chay ophiolitic mélange zone, documents a temporal heterogeneity between the M1, M2, M3, and M4 units, which formed at 310–270 Ma, 265–250 Ma, 245–240 Ma, and 310–255 Ma, respectively. The different components and provenances of each unit reflect a strike-parallel heterogeneity (Fig. 1). The M1 unit was mainly sourced from the Paleozoic sedimentary rocks of the Indochina Block (IB). The main provenance for the M2 unit is Emeishan Large Igneous Province (ELIP). The magmatic arc developed in the IB provided the materials for the M3 unit, and the detrital materials of the M4 were mainly sourced from the South China Block (SCB) (Fig. 1). The Cenozoic strike-slip deformation led to an inverted geometry of the M1, M2, and M3 units, accounting for a strike-perpendicular heterogeneity straight to the strike of the orogenic belt. The temporal, strike-parallel, and strike-perpendicular heterogeneity help us to decipher the tempo-spatial evolution of the Paleo-Tethys. The M1, M2, M3, and M4 units contain information from different evolutionary stages, likely recording the comprehensive history of the ancient oceanic basin. Importantly, our results demonstrate that both the active continental margin of the IB and the passive continental margin of the SCB acted as provenance sources that supplied significant amount of detrital material in the ophiolitic mélange matrix, indicating that the Paleo-Tethys Ocean was a “narrow” or “limited” ocean rather than the archipelagic ocean proposed before.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 42--43
1731-0830

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Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 21.

Tytuł:

Palaeobiogeography of Late Bajocian–Tithonian ammonites of northeastern Iran

Autorzy:

Majidifard, Mahmoud Reza

Powiązania:

https://bibliotekanauki.pl/articles/24202130.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
palaeobiogeography
Iran

Opis:

Jurassic rocks are widely distributed and superbly exposed in the Alborz Mts. (northern Iran) and Koppeh Dagh (northeastern Iran). The Lower Jurassic and large parts of the Middle Jurassicare characterized by a thick siliciclastic succession, whereas the Upper Bajocian to Tithonian rocks are predominantly carbonates, which represent a platform, slope and basin system. The Upper Bajocian-Tithonian ammonite faunas the NNE Iran are mostly of Submediterranean affinity, but elements of Subboreal, Mediterranean, and Ethiopian provinces are occasionally intermingled. Palaeobiogeographically the Late Bajocian to Bathonian ammonites belong to Submediterranean Province, as elsewhere in north and central Iran. This is supported by the occurrence of ammonites such as Garantiana and Morphoceras and some cosmopolitan taxa such as Cadomites and Oxycerites. In order to unravel the origin of the faunal elements and their migration routes, the relationship of the ammonite fauna of Iran to that of other regions was evaluated. On the whole, at the species level, the Toarcian to Early Bajocian ammonite faunas of northern and central Iran show a close relationship to that of northwestern Europe. A characteristic feature of this fauna is the scarcity of Phylloceratidae (accounting for less than 1% up to 3%) and the absence of Lytoceratidae. Remarkably, from Late Bathonian onward to Kimmeridgian, Phylloceratidae account for more than 50% of the ammonites fauna. Palaeogeographic reconstructions show the position of the Iranian plate (North and Central Iran) during the Middle Jurassic time at the southern margin of Eurasia at a palaeo-latitude of around 30° N which rather corresponds to European regions (Enay & Cariou, 1997). The open migration routes across pericontinental shelf seas along the northern Tethyan margin that were approximately parallel to palaeo-latitudes may explain the strong affinities of the Late Bajocian–Bathonian ammonites of northern and Central Iran to those of the Submediterranean Province. The Callovian ammonite fauna has a typical northwest Tethyan character, and belong to the Submediterranean faunal province (Seyed-Emami et al., 2013), and are largely dominated by Phylloceratidae ammonites. These pelagic taxa that preferred open oceanic conditions are accompanied consistently by Perisphinctidae, Reineckeiidae, Oppeliidae (Hecticoceratinae), Macrocephalitidae , Tulitidae, Aspidoceratidae (Parawedekindia, Peltoceras). On the other hand, this is supported by the occurrence of Submediterranean ammonites such as Macrocephalites, Pachyceras, and some cosmopolitan taxa such as Hecticoceras and Reineckeia. Some taxa from the Oxfordian- Kimmeridgian belong to the Western Tethys Province (Sequeirosia and Passendorferia) or Subboreal Province (Cardioceras). It is remarkable that, besides some cosmopolitan ammonites, there is no direct connection with faunas from southwestern Iran, western India and the southern Tethys. Finally, the Tithonian ammonite faunas of northeastern Iran are mostly of Submediterranean affinity (Seyed-Emami et al., 2013). However elements of the Mediterranean faunal provinces occasionally occur. In order to unravel the origin of the faunal elements and their migration routes, the relationship of the ammonite fauna of Iran to that of other regions need to be analysed in the future. Especially the appearance of several allegedly regionally restricted Ataxioceratidae such as Phanerostephanus, Nannostephanus, Nothostephans and the Oppeliidae as Oxylenticeras, which occur in Ethiopian Province (Page, 2008) is of great palaeobiogeographical interest.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 46--46
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 22.

Tytuł:

Stratigraphy of the Jajarkot nappe: finding the rocks of the Tethys province

Autorzy:

Lamsal, Sunil
Paudyal, Kabi Raj

Powiązania:

https://bibliotekanauki.pl/articles/24202133.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

stratigraphy
Tethys
Nepal

Opis:

There are several thrust sheets in the Lesser Himalayan region of Nepal. The Jajarkot nappe is one of them. It is located immediately west of the Kahun Klippe and east of the Karnali Nappe. There is no unified stratigraphy established for this thrust sheet. In the present research, an attempt was made to establish the stratigraphy of the Jajarkot nappe to fulfill the research gap. Previously described by Fuchs & Frank (1970) and Sharma (1980), the Jajarkot nappe in western Nepal have two distinctive crystalline lithological units: the Chaurjhari Formation and Thabang Formation. The previous unit consists of garnet-grade schist, and quartzites, with intrusions of basic rocks and granites, while the later unit consists of grey to brown crystalline limestones with biotite-quartz-schists. An unconformity is observed above the Thabang Formation. The younger geological unit above the unconformity is mapped as the Jaljala Formation, which is composed of finegrained calcareous sandstone and calcareous siltstone with minor proportions of limestones and grey-green slates. At present work, a preliminary geological study was carried out to work on the stratigraphy of the Jajarkot nappe in the Jaljala areas at 1:25,000 scales. Fossils of crinoids are found in the rock unit of the Jaljala Formation. These fossils are considered the index fossils of the Silurian. In this case, the Jaljala Formation would be equivalent to the rocks of the Tethyan affinity, and further study is under progress. The concept that the thrust sheets are moved from north to south in the Himalayas will be evidenced by these findings. An attempt is made to correlate the presently found fossils with the crinoids of the Phulchauki Group of the Kathmandu nappe and with the root zone of the Tethys succession.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 41--41
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 23.

Tytuł:

The Banda Arcs and Carpathia/Pannonia: new insights on the Tethys Twins

Autorzy:

Milsom, John

Powiązania:

https://bibliotekanauki.pl/articles/24202142.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
Carpathians
Pomerania

Opis:

The Outer Banda and Carpathian arcs, of eastern Indonesia and Europe respectively, are examples of the highly arcuate fold-and thrust belts enclosing extensional basins that have been named oroclines. Both regions have experienced large scale extension within what is, overall, a compressive regime created by the convergence of major continental blocks and, despite major differences stemming from the quasi-oceanic setting of the one and intracontinental the setting of the other, there are reasons to suppose that comparative studies may produce insights into the evolution of both areas (Milsom, 2000). Processes in the Banda region are in some respects more open to direct examination, because extension is more recent, deep seismic activity is more widespread and basement structures are not concealed beneath thick sediment cover. To a considerable extent these advantages have compensated for the disadvantages of poor access and a relatively sparse database. The final two decades of the Twentieth Century saw rapid advances in understanding the area in terms of both geology and geophysics. In the first decade of the 20th century the techniques of seismic tomography began to be applied (Hall & Spakman, 2003) and confirmed the earlier interpretation, based on hypocentre locations, of the presence of a single, scoop-shaped, slab underlying the Banda Sea (Milsom, 2001). Intensive field and laboratory studies of Seram, the largest island in the northern part of the Outer Arc, then identified exposures of rocks metamorphosed at ultra-high temperature in the vicinity of the crust-mantle boundary, which led to the abandonment of the earlier interpretations of the associated ultramafic rocks as ophiolitic (Pownall et al., 2013). The extreme extension that brought these rocks to the surface also affected the subducted lithosphere that underlies the Banda Sea, and is one of the many pointers to the importance of asthenospheric flows in creating the present situation. While similar in many respects, the Carpathia-Pannonia area shows an orocline at a much later stage in its evolution, with some evidence concealed by later overprinting and some processes that would have been important in earlier stages now no longer occurring. On the other hand, some other aspects of orocline formation are likely to be better displayed there than in the Banda region. The now increasingly well determined history of the destruction of the Western Tethys and the development of the Alps-Carpathian-Dinarides orogen (e.g. Handy et al., 2015) offers strong support for theories involving mantle flow as a key factor in orocline formation.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 50--51
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 24.

Tytuł:

Red algae grains from the Żurawnica Sandstone Member in the Sucha Beskidzka area (Magura Nappe, Polish Outer Carpathians) as the indicator of shallow water palaeoenvironment on the intrabasinal Tethyan ridge

Autorzy:

Koczur, Maria
Waśkowska, Anna
Bassi, Davide

Powiązania:

https://bibliotekanauki.pl/articles/24202109.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
paleoenvironment
Magura Nappe

Opis:

The Żurawnica Sandstone Member was deposited in the Paleocene on the northern slope of the Magura Basin in the western part of the Tethys. It is built of clastic material transported by gravitational currents from shallow parts of the Foremagura Ridge (Cieszkowski et al., 1999), which was an uplifted intrabasinal structure. At the top of the Żurawnica Hill (Beskid Makowski, location known as Kozie Skały) a well-exposed section crops out. It is a part of flysch succession of the Magura Nappe (Cieszkowski et al., 2006). In the lower part of the section thick-bedded sandstone with red algal grains occurs. Algal remnants were redeposited from the photic zone of the carbonate platform, which developed on the Foremagura Ridge. Their structure-taxonomic differentiation allows to reconstruct algal palaeoenvironment. The red algae are represented by Sporolithaceae, Melobesioideae, and Mastophoroideae genera. They correspond to three algal facies: debris, algal pavement facies, and Melobesioideae rhodolith pavement facies. Sand-sized red algal grains are the most numerous. They are fragmented and well rounded crustaceous algal thalli, typically with no traces of bioerosion. They represent algal debris facies, which was developed in high energy environment (Nebelsick et al., 2005). Red algae grains could be fragmented and rounded during turbidity transport, but considering the different degree of abrasion, especially in gravel fraction, it should be assumed that the rounding took place before the turbidity transportation. Two types of gravel grains are present: not rounded algal limestone clasts and rhodoliths. The non-rhodolith grains are built of encrusting (layered and foliose), warty, and lumpy algal crusts. Rhodoliths can be divided into two types: irregular and regular ones. Irregular rhodoliths are up to 3 cm in diameter. They contain large nuclei constituting grain skeleton. Both non-rhodolith grains and irregular rhodolits are polygeneric and contain numerous benthic organisms (bryozoans, encrusting foraminifera, and bivalves) between algal lamella, as well as constructional voids. They are bioeroded. They are elements of algal pavement facies for which the occurrence of the algal buildups with irregular rhodoliths in areas, where the energy of the environment is a bit higher is typical (Nebelsick et al., 2005, 2013; Bassi et al., 2017). The regular rhodoliths, up to 0.5 cm in size, contain small carboniferous nuclei. Typically, they are unigeneric (Sporolithaceae, Melobesioideae) and not contain other benthic organisms. Lack of constructional voids was observed in thick algal encrustation. Only encrusting growth form was observed. Regular rhodoliths are typically developed as a main part of Melobesioideae rhodoliths pavement facies, which is rather “deep” water facies of high energy environments (Adey, 1986; Bassi et al., 2017).

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 35--35
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 25.

Tytuł:

Late Cretaceous palaeoenvironmental and tectonostratigraphic reconstructions on the Polish sector of Peri-Tethys

Autorzy:

Kwietniak, Anna
Łaba-Biel, Anna
Urbaniec, Andrzej
Filipowska-Jeziorek, Kinga

Powiązania:

https://bibliotekanauki.pl/articles/24202128.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Tethys
paleoenvironment
Late Cretaceous

Opis:

The study area is located in the central part of the Carpathian Foreland in Poland (Fig. 1), and the analysed interval includes mixed carbonate-clastic sediments of the Upper Cretaceous and the uppermost part of the profile of carbonate sediments of the Upper Jurassic. The sedimentation of the studied formations during the Late Jurassic and Cretaceous took place in the shelf zone of the northern, passive margin of the Tethys Ocean. The western Tethys, unlike its eastern margins, was not a single open ocean; rather, it covered many small plates, Cretaceous island arcs and microcontinents (Palcu & Krijgsman, 2023). The spatial range of the subbasins created between these islands was significantly limited, resulting in a large diversity of palaeoenvironments and the mixed carbonate-clastic sediments of a shallow sea. The entire Upper Jurassic to Cretaceous complex can be viewed as a carbonate platform that lasted almost until the end of the Late Cretaceous with an episode of Early Cretaceous erosion. The sedimentary cover formed at that time initially reached considerable thickness (presumably about 2,000 m). Dislocation and bathymetric differentiation within the carbonate platform initiated the development of a complex depositional environment. During the Late Cretaceous, the syndepositional activity of NW-SE dislocation sequences resulted in an extensive flexural deflection within the Upper Jurassic-Lower Cretaceous sedimentary complex and lowermost part of the Upper Cretaceous complex. The resulting accommodation space was filled with a complex of Upper Cretaceous carbonate formations within which there are intervals with a significant share of siliciclastic material. At the end of the Late Cretaceous as well as in the Paleocene, movements of the Laramie phase led to the re-uplift of the analysed part of the Carpathian Foreland. During this tectonic episode, the reactivation of an older fault system occurred, mainly in the NW-SE directions. The Upper Cretaceous formations deposited in the flexural depression underwent a partial inversion and intensive erosion process, lasting until the beginning of the Neogene, which contributed to the reduction of thicknesses or the removal of some of the Upper Cretaceous formations, especially in the areas, adjacent to the major dislocations. The material for analysis consisted of 3D seismic data and geological information from the wells. In the scope of the project, we approached linking 3D seismic image and well data to reconstruct, as detailed as possible, the palaeoenvironment of the studied segment of the Late Cretaceous basin based on the chronostratigraphic method. The analysis shows various palaeomorphological elements that can bring insight into the sedimentation environments (Fig. 2). The significant influence of tectonic processes on the depositional history of the sedimentary basin was also evidenced. The tectonostratigraphic interpretation divided the Late Cretaceous sediments into two different tectonic phases (Łaba-Biel et al., 2023). Analysis of a thick Miocene interval that overlies directly on the Mesozoic formations enabled to reason about the influence of the Alpine orogenesis on the study area that was manifested by the reactivation of major regional faults in the central part of the Carpathian Foreland. This phase is directly related to the stage of progressive closure of the Tethys Ocean due to the collision of tectonic plates.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 39--40
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 26.

Tytuł:

Cephalopod fauna and stratigraphy of the Adnet type red deposits of the Krížna unit in the Western Tatra Mountains, Poland

Autorzy:

Myczyński, R.
Jach, R.

Powiązania:

https://bibliotekanauki.pl/articles/191903.pdf

Data publikacji:

2009

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

ammonites
nautiloids
Toarcian
Western Tethys

Opis:

The Lower Jurassic Adnet type red limestones and marlstones (Kliny Limestone Member, Huciska Limestone Formation) of the Krížna unit in the Tatra Mountains comprise cephalopod fauna represented by ammonites, belemnites and rarely by nautiloids. Ammonites belong to the families Phyloceratidae, Lytoceratidae, Hildoceratidae and Dactylioceratidae and indicate Early Toarcian Serpentinum Zone, Middle Toarcian Bifrons Zone (most probably Sublevisoni and Bifrons Subzones) and Late Toarcian Pseudoradiosa Zone. Hence, the age of Adnet type deposits may be estimated as Early Toarcian-Late Toarcian. Relatively moderate diversity of ammonite assemblage is noticed. Ammonites and nautiloids are preserved mainly as internal moulds, only some specimens display preserved calcified shells. Part of this macrofauna has resedimented character. Studied ammonite assemblage is closely related to that of the Mediterranean Province.

Źródło:

Annales Societatis Geologorum Poloniae; 2009, 79, No 1; 27-39
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 27.

Tytuł:

Foraminifers from the early basin of the Polish Outer Carpathians: relationship with the Western and Eastern Tethys (Tithonian)

Autorzy:

Szydło, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/24202099.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Polish Outer Carpathians
Tethys
foraminifers

Opis:

The formation of the Polish part of the Outer Carpathian Basin was initiated by the rifting process which led to the collapse and disintegration of the southern margins of the European Platform in the Late Jurassic. Fragments of carbonate platform were incorporated into the basin structures which divided the area into several sedimentary zones located at different depth. Under these conditions, most of the carbonate sediments were transported to the basin in the form of submarine landslides and gravity flows of varying densities, or accumulated during pelagic sedimentation. These deposits belong to two formations exposed in the westernmost part of the Polish Outer Carpathians, located near the Polish-Czech border. The first is mainly represented by the Tithonian marls (Vendryne Fm.) which also contain redeposited carbonate rocks and fossils (Oxfordian-Tithonian), the second is composed of limestones and marly shales of the late Tithonian-Berriasian (Cieszyn Limestone Fm.). These oldest sedimentary rocks in the Polish Outer Carpathians contain mainly benthic foraminifers and very scarce plankton occurring in exotic blocks and sometimes directly in sediments forming both formations. The first group includes forms with calcareous walls and also cemented with siliceous or calcareous material. Calcareous benthic forms belong mainly to Vagulinidae (Vaginulina, Vaginulinopsis, Astacolus, Citharina, Citharinella, Lenticulina, Palmula), Nodosariae (i.e. Frondicularia, Nodosaria, Dentalina), Epistominidae (Epistomina), and Polymorphinidae (Guttulina), while agglutinated taxa are represented by Verneulinidae (Uvigerinammina, Paleogaudryina, Belorussiella, Verneuilina), Andercotrymidae (Praedorothia, Protomarssonella, Pseudomarssonella) and Textulariopsidae (Bicazammina, Hagimashella, Textulariopsis). They can be related to the Jurassic shelf microfauna, which are known both from the Tethys and the European Platform. Among foraminiferal benthos there are also very rare aggluinated taxa belonging to several genera: Melathrokerion, Buccicrenata, Alveosepta, Pseudocyclammina, and the more common calcareous forms of Andersenolina, Neotrocholina, Trocholina, Paalzowella, as well as of Discorbis, which inhabited shallow marine environments formed around the elevations within the basin as well as on its coast. Recently, apart from the benthic microfauna isolated Globigerina-like forms have been also found in the Tithonian deposits. These few forms resemble early planktonic foraminifera of the Western Tethys (Gl. oxfordiana, F. hoterivica) as well as the taxa known epicontinental and subTethyan seas located north (“Gl.” stellapolaris) and east (Gl. balakhmatovae, G. terquemi) of the studied area. The taxonomy, abundance and state of preservation of the described foraminifera from the early basin of the Polish Outer Carpathians indicate a connection with the gradually degraded areas of the platform inhabited by benthic and plankton communities from both the Tethyan and Boreal seas. The studied foraminifera resemble the microfauna of Western and Eastern Tethys and adjacent platforms.

Źródło:

Geotourism / Geoturystyka; 2023, 1-2 (72-73); 70--70
1731-0830

Pojawia się w:

Geotourism / Geoturystyka

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 28.

Tytuł:

Middle Triassic evolution of the northern Peri-Tethys area as influenced by early opening of the Tethys Ocean
Ewolucja środkowotriasowa północnej Paratetydy i jej związki z rozwojem Oceanu Tetydy

Autorzy:

Szulc, J.

Powiązania:

https://bibliotekanauki.pl/articles/191262.pdf

Data publikacji:

2000

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

late Scythian-Carnian
Tethys
Peri-Tethys
basin analysis
sequence stratigraphy
paleogeography
paleoenvironments

Opis:

During Middle Triassic times, the Germanic or northern Peri-Tethys Basin pertained to the western Tethys Ocean. The basin was closed from the north and open toward the Tethys by tectonically controlled depressions (gates). The gates were opened in different times. The marine incursions broke first (as early as in late Scythian time) through the eastern gates and from the Polish Basin advanced gradually to the west. Semiclosed disposition of the basin resulted in its distinctive environmental diversification. Open marine environments developed along the southeastern margins which should be regarded as an integrate part of the Tethys Ocean rather than the epicontinental sea. Northward and westward from the Silesian and Carpathian domains the environments became more restricted. This resulted in significant facies diachronity between the western and eastern parts of the basin. As indicated by the faunal diversity, facies variability and geochemical properties of the sediments, during almost entire Anisian time the open marine sedimentation dominated in the eastern part while the western part displayed restricted circulation, typical for the semi-closed, evaporitic basin. The circulation reversed in Ladinian time when the westward shift of the tethyan spreading center gave rise to opening of the western gate. Meanwhile, the eastern and northern parts of the basin were uplifted and underwent emersion by the end of the Ladinian. Evolution of the southern parts of the Germanic Basin (Silesia, Holy Cross Mts., SW Germany) has been directly influenced by the Tethys rifts. The crustal motion was transmitted from the Tethys rift onto its northern periphery by reactivated Hercynian master faults. The Northern Germany and the North Sea basins were controlled by the North Atlantic-Arctic rift system. The central part of the basin was dominated by thermal subsidence. Despite of the intense synsedimentary tectonism affecting the basin, the distinguished 3rd order depositional sequences resulted from eustatic controls. The concordance between the tethyan and peritethyan sequence stratigraphy argues for the overregional, eustatic nature of the sequences. Faunal migration from the Tethys into its northern periphery followed generally the rift-controlled opening of the seaways within the Tethys. The first tethyan faunas which appeared in the south-eastern part of the Polish Basin as early as in Induan time came from the eastern branch of the Tethys Ocean (Paleo-Tethys). The next migration waves proceeded by western branches of the spreading ocean (Neo-Tethys) and entered the Germanic Basin through the Silesian-Moravian Gate (in Anisian time) and through the Western Gate from Ladinian time onward.
W czasie środkowego triasu basen germański należał do północnego obrzeżenia Oceanu Tetydy nazywanego północną Perytetydą. Taka pozycja paleogeograficzna wskazuje że basen germański należy traktować raczej jako integralną część zachodniej Tetydy niż jako typowy basen epikontynentalny. Bezpośrednie połączenie między obszarem germańskim a Tetydą utrzymywane było przez system tektonicznie generowanych obniżeń (bram) rozwiniętych w obrębie speneplenizowanego lądu windelicko-bohemskiego stanowiącego strukturalną barierę między otwartym oceanem i jego strefą peryferyjną. Przez większą część środkowego triasu basen germański wykazywał cechy basenu półzamkniętego o ograniczonej i jednokierunkowej cyrkulacji. Taki układ hydrologiczny powodował ewaporacyjny wzrost zasolenia wód basenu w miarę oddalania się od strefy dopływu wód oceanicznych. Znajduje to potwierdzenie w wyraźnym ubożeniu zespołów fauny zasiedlającej zbiornik jak i w zapisie izotopów stabilnych węgla i tlenu. Otwieranie bram miało charakter diachroniczny i postępowało ze wschodu na zachód. Najwcześniej, bo już w środkowej części wczesnego triasu otwarta była tzw. Brama Wschodniokarpacka. W anizyku głównym połączeniem była Brama Morawsko-Śląska a w ladynie Brama Zachodnia. Diachronizm w otwieraniu bram był pochodną migracji głównej strefy spreadingu tetydzkiego, która przemieszczała się ze wschodu na zachód. Wyróżnione dla basenu germańskiego sekwencje depozycyjne trzeciego rzędu wykazują dobrą korelację z sekwencjami z basenów alpejskich co pozwala stwierdzić, że cykle transgresywno-regresywne w basenie germańskim kontrolowane były głównie przez wahania eustatyczne. Subtropikalna pozycja paleogeograficzna północnej Perytetydy warunkowała jej gorący i półsuchy klimat. Okresowe zwilgotnienia w późnym ladynie i w karniku były pochodną przebudowy tektonicznej i intensywnej działalności wulkanicznej w obrębie Tetydy.

Źródło:

Annales Societatis Geologorum Poloniae; 2000, 70, 1; 1-48
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 29.

Tytuł:

Magnetostratigraphy of the Jurassic/Cretaceous boundary interval in the Western Tethys and its correlations with other regions: a review

Autorzy:

Grabowski, J.

Powiązania:

https://bibliotekanauki.pl/articles/2061000.pdf

Data publikacji:

2011

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

magnetostratigraphy
Tithonian
Berriasian
Western Tethys

Opis:

Magnetostratigraphy is an important method in regional and worldwide correlations across the Jurassic/Cretaceous boundary. The M-sequence of magnetic anomalies, embracing this boundary, provides an easily recognizable pattern which might be identified in biostratigraphically calibrated land sections. The polarity chrons between M21r and M16n are well correlated to calpionellid and calcareous nannofossil stratigraphy in the Tethyan Realm. This results in a very high precision of stratigraphic schemes of pelagic carbonates (ammonitico rosso and maiolica limestones), integrating the two groups of fossils with magnetostratigraphy. The main clusters of the reference sections are located in the Southern Alps and Apennines, but the database was recently enriched by sections from the Western Carpathians and Eastern Alps. Quite a few Jurassic/Cretaceous boundary sections with magnetostratigraphy are known in the Iberian Peninsula and south-eastern France but their importance relies on the integration of magnetostratigraphy also with the Tethyan ammonite zonation. Correlation of Boreal and Tethyan regions still remains a major problem. Just two sections with reliable correlation to the global polarity time scale are documented outside Tethys: a shallow marine to non-marine Tithonian–Berriasian–Valanginian sequence in southern England (Portland–Purbeck beds) and the marine clastic Upper Tithonian–Middle Berriasian (= Middle Volgian–lowermost Ryazanian) sequence at Nordvik Peninsula (Siberia). The Volgian/Ryazanian boundary at Nordvik seems to be located in the lower part of magnetochron M18n, while the most commonly accepted definitions of the Tethyan Jurassic/Cretaceous boundary are situated either within magnetochron M19n (A/B calpionellid zonal boundary, Durangites/Jacobi ammonite zonal boundary), or at the boundary of M19n/M18r (Jacobi/Grandis ammonite subzonal boundary).

Źródło:

Volumina Jurassica; 2011, 9, 1; 105-128
1896-7876
1731-3708

Pojawia się w:

Volumina Jurassica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 30.

Tytuł:

Triassic micro-charcoal as a promising puzzle piece in palaeoclimate reconstruction: An example from the Germanic Basin

Autorzy:

Götz, Anette E.
Uhl, Dieter

Powiązania:

https://bibliotekanauki.pl/articles/2171822.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

wildfire
palaeoclimate
Triassic
Peri-Tethys
Germany

Opis:

Fossil charcoal is the primary source of evidence for palaeo-wildfires and has gained increasing interest as a proxy in the reconstruction of past climates and environments. Today, increasing temperatures and decreasing precipitation/humidity appear to correlate with increases in the frequency and intensity of wildfires in many regions worldwide. Apart from appropriate climatic conditions, sufficient atmospheric oxygen (>15%) is a necessary precondition to sustain combustion in wildfires. The Triassic has long been regarded as a period without evidence of wildfires; however, recent studies on macro-charcoal have provided data indicating their occurrence throughout almost the entire Triassic. Still, the macro-palaeobotanical record is scarce and the study of micro-charcoal from palynological residue is seen as very promising to fill the gap in our current knowledge on Triassic wildfires. Here, the authors present the first, verified records of micro-charcoal from the Triassic of the Germanic Basin, complementing the scarce macro-charcoal evidence of wildfires during Buntsandstein, Muschelkalk and Keuper (Anisian-Rhaetian). The particles analysed by means of scanning electron microscopy (SEM) show anatomical features typical of gymnosperms, a major element of the early Mesozoic vegetation following the initial recovery phase after the PT-boundary event. From the continuously increasing dataset of Triassic charcoal, it becomes apparent that the identification of wildfires has a huge potential to play a crucial role in future studies, deciphering Triassic climate dynamics. The first SEM study of micro-charcoal from palynological residue spanning the entire Triassic period, presented here, is a key technique to further unravel the charcoal record as a puzzle piece in palaeoclimate reconstruction.

Źródło:

Annales Societatis Geologorum Poloniae; 2022, 92, 3; 219--231
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 31.

Tytuł:

Upwelling regime in the Carpathian Tethys: a Jurassic-Cretaceous palaeogeographic and paleoclimatic perspective

Autorzy:

Golonka, J.
Krobicki, M.

Powiązania:

https://bibliotekanauki.pl/articles/2059324.pdf

Data publikacji:

2001

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Tethys
Carpathians
Jurassic
Cretaceous
palaeogeography
palaeoclimate
palaeoecology
upwelling

Opis:

Jurassic and Cretaceous global palaeogeographic reconstructions show a changing configuration of mountains, land, shallow seas and deep ocean basins, and these are used as input for paleoclimatic modelling. We have generated Oxfordian-Kimmeridgian, Tithonian-Berriasian and Barremian-Hauterivian paleoclimatic maps, showing air pressure, wind directions, humidity zones and areas favourable to upwelling conditions, modelled by the PALEOCLIMATE program and plotted on the palaeogeographic background. Paleoclimate modelling suggests that prevailing Jurassic-Cretaceous winds in the northern Tethys area came from south-south-west, and may have been parallel to the Czorsztyn Ridge, uplifted as a result of extension during the Jurassic supercontinental breakup. Upwelling may have been induced at the southeastern margin of the ridge. The model is consistent with the rock records within the earliest Cretaceous deposits. The presence of phosphates and a palaeoenvironmental analysis of benthic fauna support the upwelling model.

Źródło:

Geological Quarterly; 2001, 45, 1; 15-32
1641-7291

Pojawia się w:

Geological Quarterly

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 32.

Tytuł:

Temporal dynamics of the geographic differentiation of Late Devonian Palmatolepis assemblages in the Prototethys

Autorzy:

Girard, C.
Ta, H.P.
Savage, N.
Renaud, S.

Powiązania:

https://bibliotekanauki.pl/articles/22384.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Instytut Paleobiologii PAN

Tematy:

paleontology
temporal dynamics
geographic differentiation
Late Devonian
Palmatolepis
Prototethys zob.Proto-Tethys Ocean
Proto-Tethys Ocean
Conodonta
mass extinction
morphometry
Frasnian
Famennian

Opis:

Throughout their history, species had to face environmental variations spatially and temporally. How both levels of variation interact will be of key importance in conditioning their response to major perturbations. We addressed this question by focusing on a period in Earth’s history marked by dramatic environmental and faunal changes, the Late Devonian Frasnian/Famennian boundary. From a paleogeographic point of view, this period is characterized by a cosmopolitanism of the faunas across a large ocean, the Prototethys. We considered the biotic reaction at a seldom considered scale, namely within a single subgenus of conodont, Palmatolepis (Manticolepis). Patterns of spatial and temporal differentiation were quantified using morphometrics of its platform element. The recognized cosmopolitanism of the faunas was confirmed at this scale of variation since temporal records gathered in distant areas around the Prototethys, including the seldom documented regions located nowadays in South−East Asia, displayed similar morphological trends in response to the major F/F crisis. Beyond this overall cosmopolitanism, subtle geographic structure was evidenced but was not stable through time. Geographic differentiation was maximal shortly before the F/F crisis, suggesting that despite high sea−level, tectonics leaded to complex submarine landscapes promoting differentiation. In contrast any geographic structure was swamped out after the crisis, possibly due to a global recolonization from few favorable patches.

Źródło:

Acta Palaeontologica Polonica; 2010, 55, 4
0567-7920

Pojawia się w:

Acta Palaeontologica Polonica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Glaucony from the condensed Lower-Middle Jurassic deposits of the Križna Unit, Western Tatra Mountains, Poland

Autorzy:

Jach, R.
Starzec, K.

Powiązania:

https://bibliotekanauki.pl/articles/191514.pdf

Data publikacji:

2003

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

High-Al autochthonous glaucony
K-Ar dating
Carpathians
Tethys

Opis:

Lower-Middle Jurassic glaucony-bearing deposits crop out in the Polish part of the Križna Unit in the Western Tatra Mts. These deposits, up to 20 cm thick, consist of glaucony-rich marls and limestones. The glaucony grains constitute up to 30% volume of the deposits. They represent an evolved stage of glauconitization since they contain more than 7% K₂O. The content of Al₂O₃ is high (up to 19.97%, average 16.98%) while the content of Fe₂O₃ is low (not more than 23.48%, average 12.84%). These features are interpreted as a product of diagenetic processes. The glaucony-bearing deposits were formed at an upper bathyal depth and their rate of deposition was very low, what allowed long-lasting evolution of the glaucony grains. The K-Ar age of the glaucony grains is much younger than the biostratigraphic age of the studied section. The lowering of the K-Ar dates is interpreted as a result of loss of radiogenic Ar from the lattice of the glaucony.

Źródło:

Annales Societatis Geologorum Poloniae; 2003, 73, No 3; 183-192
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 34.

Tytuł:

Bositra limestones - a step towards radiolarites: case study from the Tatra Mountains

Autorzy:

Jach, R.

Powiązania:

https://bibliotekanauki.pl/articles/191672.pdf

Data publikacji:

2007

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

thin-shelled bivalves
Middle Jurassic
Krížna Basin
Carpathians
Western Tethys

Opis:

Bositra limestones of Aalenian–Lower Bathonian age crop out in the Krížna unit in the Western Tatra Mountains (Poland). They are sandwiched between pelagic red limestones and radiolarites and display lateral facies variation. Four facies were distinguished: (i) Bositra packstones/grainstones, (ii) crinoidal packstones/ grainstones, (iii) Bositra-crinoidal packstones, and (iv) Bositra-radiolarian wackestones. The Bositra packstones/ grainstones were laid down in high-energy setting, while Bositra-radiolarian wackestones in calm condition. Crinoidal packstones/grainstones represent density current deposits. Bositra-crinoidal packstones resulted from intense bioturbation and mixing of crinoidal packstones/grainstones with background Bositra-rich deposits. Topographic gradient affected the lateral facies variation. Taphonomic factors strongly controlled by energy of the sedimentary environment, ecological factors which caused domination of Bositra bivalves in benthos assemblage and dissolution eliminating non-calcitic bioclasts could resulted in formation of the Bositra limestones. The eutrophication of water column and remodelling of the Krížna Basin, which finally led to deposition of radiolarites seem to be of considerable importance. Hence, Bositra limestones can be regarded as the record of the interme- diate stage of the basin evolution towards radiolarite formation.
Wapienie bositrowe wczesnego aalenu–wczesnego batonu, które odsłaniają się w jednostce kriżniańskiej w Polskich Tatrach Zachodnich znajdują się w profilach pomiędzy pelagicznymi czerwonymi wapieniami a radiolarytami (Fig. 1, 2; Lefeld et al., 1985; Gradziński et al., 2004). Wapienie te wykazują wyraźne facjalne zróżnicowanie. Wydzielone zostały następujące facje: (i) bositrowe pakstony/greinstony, (ii) krynoidowe pakstony/greinstony, (iii) bositrowo-krynoidowe pakstony i (iv) bositrowo-ra diolariowe wakstony (Fig. 2, 3). Bositrowe pakstony/greinstony powstały w środowisku o stosunkowo wysokiej energii, a bositrowo- radiolariowe wakstony w warunkach niskiej energii. Krynoidowe pakstony/greinstony są interpretowane jako osady prądów gęstościowych, a bositrowo-krynoidowe pakstony jako osady prądów gęstościowych zbioturbowane i zmiksowane z osadami tła depozycyjnego. Zróżnicowana morfologia basenu wpłynęła na oboczną zmienność facjalną omawianych wapieni i przestrzenny rozkład facji (Fig. 4). Powstanie wapieni bositrowych było warunkowane przez czynniki natury tafonomicznej, związane z energią środowiska sedymentacji, natury ekologicznej decydujące o dominacji bositr w zespole bentosu i procesy rozpuszczania eliminujące nie kalcytowe bioklasty. Postępująca eutrofizacja wód (Bartolini & Cecca, 1999; Cobianchi & Picotti, 2001) i przemodelowanie basenu kriżniańskiego związane z procesami ryftingu Zachodniej Tetydy, które ostatecznie doprowadziły do depozycji radiolarytów, wydają się mieć zasadniczy wpływ na powstanie wapieni bositrowych. Tak więc, wapienie bositrowe reprezentują przejściową fację poprzedzającą w czasie powstanie tetydzkich jurajskich radiolarytów.

Źródło:

Annales Societatis Geologorum Poloniae; 2007, 77, No 2; 161-170
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 35.

Tytuł:

The Jurassic-Cretaceous boundary in Boreal Russia : radiolarian and calcareous dinoflagellate potential biomarkers

Autorzy:

Vishnevskaya, V. S.

Powiązania:

https://bibliotekanauki.pl/articles/2060606.pdf

Data publikacji:

2017

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Tithonian stages
Berriasian stages
radiolarians
calcareous dinoflagellates
Tethys
boreal
Volgian

Opis:

The International Berriasian Working Group (ISCS) suggested primary and secondary marker “datums” to fix the basal Berriasian boundary and thus to detine the Jurassic-Cretaceous boundary (Wimbledon et al., 2011, 2013). Two primary markers Calpionella, as well as calcareous nannoplankton, are practically unknown in the Boreal Realm. Testing and calibration of these markers, as well as of fossils of radiolarians and other signals, in the most complete sections, were declared as an important task for the near future. In the Tethys, the Jurassic-Cretaceous boundary based on radiolarians falls inside zone UAZ 13 of Baumgartner et al. (1995), whereas in the palaeo-Pacific it corresponds to the boundary between zones 4 and 5 of Pessagno et al. (2009), and in boreal Siberia it probably falls between the biohorizons of Parvicingula haeckeli and P. khabakovi. The radiolarian events at the Jurassic-Cretaceous boundary in the boreal successions of Russia can be proposed to be used as an additional biomarker to help develop new integrated boundary criteria. Thus, as the first appearance of the zonal species Calpionella alpina, which defines the Jurassic and Cretaceous boundary, coincides with the first occurrence of the calcareous dinocyst zonal species Stomiosphaerina proxima (Reháková, 2000), it is logical to propose a calcareous dinoflagellate, widely represented in the Upper Jurassic-Lower Cretaceous Bazhenovo Formation of Siberia, as a secondary marker.

Źródło:

Geological Quarterly; 2017, 61, 3; 641--654
1641-7291

Pojawia się w:

Geological Quarterly

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 36.

Tytuł:

Oligocene crabs (Decapoda: Brachyura) from the Asmari Formation in Yasuj area (SW Iran)

Autorzy:

Bahrami, Ali
Ossó, Alex
Yazdi, Mehdi
Ansari, Heshmatollah

Powiązania:

https://bibliotekanauki.pl/articles/27323965.pdf

Data publikacji:

2023

Wydawca:

Polska Akademia Nauk. Czasopisma i Monografie PAN

Tematy:

Paleogene
Rupelian
Tethys
Brachyura
Palaeocarpilius
Lophoranina
paleogen
rupel
Tetyda
krab

Opis:

New findings of crustacean decapod brachyurans from the Rupelian period (lower Oligocene) in Iran are presented in this study. In particular, Lophoranina sp. and Palaeocarpilius cf. P. rugifer Stoliczka, 1871, from the Rupelian strata were found in two previously unexplored localities, Abshar and Vezg near Yasuj in the southwestern region of Iran. The discovery contributes to fill the gap in the record of brachyuran decapod crustaceans in Iran during the Eocene and Miocene periods. The presence of both genera in the Oligocene of Iran suggests a certain degree of faunal similarity among brachyurans on both sides of the Tethys Realm.

Źródło:

Acta Geologica Polonica; 2023, 73, 2; 189--200
0001-5709

Pojawia się w:

Acta Geologica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 37.

Tytuł:

The Oxfordian ammonite genus Passendorferia Brochwicz Lewiński and the Tethyan subfamily Passendorferiinae Meléndez: origin and palaeobiogeography

Autorzy:

Mendez, G.
Atrops, F.
Bello, J.
Brochwicz-Lewiński, W.
Darpa, C.
Fozy, I.
Perez-Urresti, I.
Ramajo, J.
Sequeiros, L.

Powiązania:

https://bibliotekanauki.pl/articles/2061354.pdf

Data publikacji:

2009

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Upper Jurassic
ammonites
paleobiogeography
West Tethys
biostratigraphy
evolution
Mediterranean Province

Opis:

The Oxfordian ammonite group Passendorferiinae (known as "Mediterranean perisphinctids") forms a group of perisphinctids characterized by strongly evolute serpenticone coiling and subcircular to subquadrate whorl section, and forms a lateral divergent branch of the main stem Perisphinctidae. They originated probably from Late Callovian Grossouvriinae (Alligaticeras) and spread mainly in the Mediterranean (Tethyan) Province along the southern margin of Tethys, occasionally reaching the outer areas of epicontinental platforms. Their particular morphological features make them somewhat homoeomorphic with Tethyan Kimmeridgian Nebrodites. The phyletic link might be represented by the genus Geyssantia Meléndez, known from the Late Oxfordian Planula Chronozone. Separate biogeographic distribution in relation to the Perisphinctinae might reflect a progressive differentiation of western Tethyan faunas at the Callovian-Oxfordian boundary and at the onset of the Middle Oxfordian Transversarium Chronozone. Their rapid evolution gives them a biostratigraphic value similar to that of the Perisphinctinae. At the turn of the Middle-Late Oxfordian they gave rise to early Ataxioceratinae (Orthosphinctes), which replaced the Perisphinctinae in epicontinental areas, and colonised the marginal epicontinental blocks of northern Tethys. The taxonomy of this group is based upon the recognition of sexual dimorphism, using a single generic and specific name for both (M) and (m), and hence rejecting the use of former subgeneric ames for both dimorphs. A new species within this line: Passendorferia nodicostata sp. nov. from the Plicatilis Biozone (Paturattensis Subbiozone) is defined and described for the first time.

Źródło:

Volumina Jurassica; 2009, 7, 1; 113-134
1896-7876
1731-3708

Pojawia się w:

Volumina Jurassica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 38.

Tytuł:

Pliensbachian, Early Jurassic radiolarians from Mount Rettenstein in the Northern Calcareous Alps, Austria

Autorzy:

Cifer, T.
Gorican, S.
Gawlick, H.-J.
Auer, M.

Powiązania:

https://bibliotekanauki.pl/articles/2082123.pdf

Data publikacji:

2020

Wydawca:

Polska Akademia Nauk. Instytut Paleobiologii PAN

Tematy:

Radiolaria
Polycystina
systematics
stratigraphy
Jurassic
Western Tethys
Eastern Alps
Austria

Opis:

One of the best preserved Early Pliensbachian radiolarian assemblages from the Western Tethys is described from the grey marly limestone exposed at Mount Rettenstein in the Northern Calcareous Alps, south of the Dachstein Massif. Fourty-five genera and 71 species are documented and illustrated here. Four species are newly described: Tozerium filzmoosense Cifer sp. nov., Loupanus pliensbachicus Cifer sp. nov., Thurstonia? robusta Cifer sp. nov., and Ares rettensteinensis Cifer sp. nov. Radiolarian age is in accordance with ammonoid data from the overlying red marly limestone, which was assigned to the upper part of the Lower Pliensbachian. The best equivalent for the radiolarian-bearing lithology is the Dürrnberg Formation, characteristic of the open-marine Hallstatt facies zone. Previously published radiolarian data from the Dürrnberg Formation were re-evaluated and the originally proposed age assignments revised. At two localities, the published Hettangian–Sinemurian age was emended to the early Early Pliensbachian that is in accordance with the age of radiolarians from Mount Rettenstein. We compared the studied fauna from Mount Rettenstein also with two other rich radiolarian assemblages, one from another locality in the Dürrnberg Formation and one from the Gümüslü Allochthon in Turkey, which were assigned to the late Early Pliensbachian and are somewhat younger than the assemblages studied herein.

Źródło:

Acta Palaeontologica Polonica; 2020, 65, 1; 167-207
0567-7920

Pojawia się w:

Acta Palaeontologica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 39.

Tytuł:

Middle to Late Jurassic carbonate-biosiliceous sedimentation and palaeoenvironment in the Tethyan Fatricum Domain, Krížna Nappe, Tatra Mts, Western Carpathians

Autorzy:

Jach, Renata
Reháková, Daniela

Powiązania:

https://bibliotekanauki.pl/articles/191204.pdf

Data publikacji:

2019

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

radiolarite
nodular limestone
Fleckenmergel facies
carbonate production crisis
calcite compensation depth
Tethys

Opis:

The Jurassic of the Alpine-Mediterranean Tethys was characterized by the formation of several interconnected basins, which underwent gradual deepening and oceanization. Sedimentation in each basin was influenced by a specific set of interrelated factors, such as tectonic activity, seawater circulation, climate, chemistry and trophic state of seawater as well as evolutionary changes of the marine biota. This paper deals with the Fatricum Domain (Central Carpathians, Poland and Slovakia), which in the Jurassic was a pull-apart basin on a thinned continental crust. The sedimentation history of this domain during the Bajocian-Tithonian and its governing factors have been revealed. Facies analysis of the Bajocian-Oxfordian deposits evidences considerable relief of the basin-floor topography. Deposits in the Western Tatra Mts represent sedimentation on a submarine intrabasinal high, whereas the coeval deposits of the eastern part of the Tatra Mts accumulated in a deeper basin. The basin succession began with Bajocian bioturbated “spotted” limestones and siliciclastic mudstones (Fleckenmergel facies). These were succeeded by uppermost Bajocian - middle Bathonian grey nodular limestones, affected by synsedimentary gravitational bulk creep. The coeval deposits of the intrabasinal high are represented by well-washed Bositra-crinoidal limestones with condensed horizons. Uniform radiolarite sedimentation commenced in the late Bathonian and persisted until the early late Kimmeridgian. The basal ribbon radiolarites (upper Bathonian - lower Oxfordian), which consist of alternating chert beds and shale partings, are a record of seawater eutrophication, a related crisis in carbonate production and the rise of the CCD, which collectively resulted in biosiliceous sedimentation. The overlying calcareous radiolarites (middle Oxfordian - lowermost upper Kimmeridgian) marked a gradual return to carbonate sedimentation. The return of conditions that were favourable for carbonate sedimentation took place in the late Kimmeridgian, when the red nodular limestones were deposited. They are partly replaced by basinal platy limestones (uppermost Kimmeridgian - Tithonian) in the Western Tatra Mts. This lateral variation in facies reflects a change in the sedimentary conditions governed by a bathymetric reversal of the seafloor configuration, attributed to a further stage in the pull-apart transcurrent tectonics of the Fatricum Domain.

Źródło:

Annales Societatis Geologorum Poloniae; 2019, 89, 1; 1-46
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 40.

Tytuł:

Late Carboniferous-Neogene geodynamic evolution and paleogeography of the circum-Carpathian region and adjacent areas
Późnokarbońsko-neogeńska geodynamiczna ewolucja i peleogeografia rejonu wokółkarpackiego i obszarów przyległych

Autorzy:

Golonka, J.
Oszczypko, N.
Ślączka, A.

Powiązania:

https://bibliotekanauki.pl/articles/191280.pdf

Data publikacji:

2000

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

plate tectonics
paleogeography
Tethys
Mediterranean
Carpathians
Carboniferous
Triassic
Jurassic
Cretaceous
neogene clays

Opis:

Twelve time interval maps were constructed which depict the plate tectonic configuration, paleogeography and general lithofacies. The aim of this paper is to provide the geodynamic evolution and position of the major tectonic elements of the area within the global framework. The Hercynian orogeny was concluded with the collision of Gondwana and Laurussia, whereas the Tethys Ocean formed the embayment between the Eurasian and Gondwanian branches of Pangea. The Mesozoic rifting events resulted in the origin of the oceanic type basins like Meliata and Pieniny along the northern margin of the Tethys. Separation of Eurasia from Gondwana resulted in the formation of the Alboran-Ligurian-Pieniny Ocean as a part of the Pangean breakup tectonic system. During the Late Jurassic-Early Cretaceous time, the Outer Carpathian rift had developed. Latest Cretaceous-earliest Paleocene was the time of the closure of the Pieniny Ocean. Adria-Alcapa terranes continued their northward movement during Eocene-Early Miocene time. Their oblique collision with the North European plate led to the development of the accretionary wedge of Outer Carpathians and foreland basin. The formation of the West Carpathian thrusts was completed by the Miocene time. The thrust front was still progressing eastwards in the Eastern Carpathians.
Dla obszaru wokółkarpackiego skonstruowano 12 map przedstawiających konfigurację płyt litosferycznych, paleogeografię i uproszczony rozkład litofacji w okresie od późnego karbonu po neogen. Przedstawiono ewolucję geodynamiczną tego rejonu na tle ruchu płyt i pozycji głównych elementów tektonicznych w globalnym układzie odniesienia. Orogeneza hercyńska zakończyła się kolizją Gondwany i Laurusji, a Ocean Tetydy utworzył zatokę pomiędzy dwom a ramionami Tetydy - Gondwaną i Laurazją. W wyniku mezozoicznych ryftów wzdłuż północnej krawędzi Oceanu Tetydy powstało szereg basenów typu oceanicznego takich jak Meliata i basen pieniński. Ocean alborańsko-liguryjsko-pieniński powstał w wyniku oddzielenia się Gondwany i Laurazji jako fragment tektonicznego sytemu rozpadu Pangei. W okresie od późnej jury do wczesnej kredy rozwinął się ryft Karpat Zewnętrznych. Na przełomie kredy i paleocenu nastąpiło zamknięcie basenu pienińskiego pasa skałkowego. W okresie od eocenu do wczesnego miocenu terany Adri-Alkapy i Karpat Wewnętrznych kontynuowały ruch w kierunku północnym, a ich kolizja z płytą euroazjatycką doprowadziła do powstania pryzmy akrecyjnej Karpat Zewnętrznych i basenu przedgórskiego. Przy końcu miocenu środkowego uformowały się ostatecznie nasunięcia Karpat Zachodnich, podczas gdy w Karpatach Wschodnich ruchy te przetrwały do końca pliocenu.

Źródło:

Annales Societatis Geologorum Poloniae; 2000, 70, 2; 107-136
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 41.

Tytuł:

Late Jurassic facies succession of the Kleszczów Graben area (southern border of the Łódź Depression, peri-Tethyan shelf, central Poland)

Autorzy:

Olchowy, Piotr
Krajewski, Marcin
Felisiak, Ireneusz

Powiązania:

https://bibliotekanauki.pl/articles/2058630.pdf

Data publikacji:

2019

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Late Jurassic
outer-inner ramp facies
Oxfordian
Kimmeridgian
Tithonian
North Tethys Shelf

Opis:

Numerous fully cored boreholes completed in the last years in central Poland (Kleszczów Graben area, southern border of the Łódź Depression) enabled the researchers to obtain new sedimentological data on the Oxfordian-Tithonian continuous sedimentary record in the Polish part of the northern Tethys shelf. Twenty-two facies were distinguished in the sedimentological succession. The facies represent the outer-, mid- and inner-ramp environments, including evaporitic episodes and palaeosols. The facies document that the Oxfordian-Lower Kimmeridgian (up to Hypselocyclum) carbonate ramp has evolved to the Upper Kimmeridgian-Tithonian carbonate-siliciclastic ramp. Among the Kimmeridgian deposits, numerous hardgrounds, tidal channel deposits and gravity flow sediments were identified. The Kleszczów Graben sedimentary succession is discussed along with the lithostratigraphical units known from the adjacent regions of southern and central Poland.

Źródło:

Geological Quarterly; 2019, 63, 4; 657--682
1641-7291

Pojawia się w:

Geological Quarterly

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:

Jurassic planktonic foraminifera from Pieniny Klippen Belt and their taxonomic and phylogenetic importance (Carpathians, southern Poland)
Jurajskie otwornice planktoniczne z pienińskiego pasa skałkowego Polski i ich znaczenie

Autorzy:

Hudson, W.
Hart, M.
Sidorczuk, M.
Wierzbowski, A.

Powiązania:

https://bibliotekanauki.pl/articles/2061222.pdf

Data publikacji:

2005

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

otwornice planktoniczne
pochodzenie
zagadnienia taksonomiczne
jura
Tethys
planktonic foraminifera
origin
taxonomical problems
Jurassic

Opis:

In this brief review of the occurrence of planktonic foraminifera in the Middle and Upper Jurassic in the Pieniny Klippen Belt (Carpathians, southern Poland), we wish to draw attention to the importance of these faunas in early evolution of the group. The appearance of planktonic foraminifera could be related to major palaeogeographic changes in the Tethys during early Middle Jurassic which induced vigorous upwelling circulation making nutritiens available in the surface waters.
Wiele wapieni pelagicznych występujących w pienińskim pasie skałkowym, zwłaszcza środkowo i górnojurajskie osady formacji wapienia czorsztyńskiego, wykazuje niezwykle liczne nagromadzenia otwornic planktonicznych. Zebrane próby pochodzą z pięciu odsłonięć, zlokalizowanych w obrębie pienińskiego pasa skałkowego, reprezentujących utwory od batonu do kimerydu (fig. 2) (por. Wierzbowski i in. 1999) - trzech z sukcesji czorsztyńskiej (Czorsztyn Zamek, potok Krupianka, Stankowa Skała) oraz dwóch z sukcesji niedzickiej (Niedzica Podmajerz, Czajakowa Skała) (fig. 1). Współczesne rozważania nad wczesną ewolucją otwornic planktonicznych (Simmons i in. 1997; Hart i in. 2003) wskazują, że dawniejsze poglądy o triasowym rodowodzie tej grupy organizmów są prawdopodobnie niesłuszne, i że wykształciła się ona dopiero na przełomie wczesnej i środkowej jury. Stan zachowania jurajskich otwornic planktonicznych w badanych płytkach cienkich przysparza jednak sporo kłopotów taksonomicznych, co dodatkowo wynika z obiektywnych trudności podania i oceny wartości cech rozpoznawczych dla poszczególnych gatunków. Znaczenie taksonomiczne szeregu cech (jak liczba komór w ostatnim zwoju, rozmiar i położenie ujścia oraz wysokość wierzchołka) jest bowiem stosunkowo ograniczone, a ekologiczne uwarunkowanie występowania tych cech jest słabo poznane. Zmienność badanych otwornic z pienińskiego pasa skałkowego w płytkach cienkich, pomimo dużego interwału stratygraficznego, z którego pochodzą (dolny baton - dolny kimeryd), jest niewielka. Wspomniane wcześniej okoliczności nie pozwalają stwierdzić n.p. jednoznacznie czy najczęściej spotykane formy należą do gatunku Globuligerina bathoniana Pazdrowa, czy też G. oxfordiana Grigelis, które różnią się zwłaszcza kształtem ujścia (pl. 1). Można się spodziewać jedynie, że okazy występujące w osadach dolnego batonu formacji wapienia niedzickiego są blisko spokrewnione, jeśli nawet nie identyczne, z gatunkiem G. bathoniana, na co może wskazywać, obserwowany niekiedy w płytkach cienkich, bardziej strzelisty kształt wierzchołka skorupki. Obfitość występowania otwornic planktonicznych w badanych osadach środkowej i górnej jury pienińskiego pasa skałkowego może mieć jednak duże znaczenie w rozważaniach nad ewolucją otwornic planktonicznych, co stanie się szczególnie wyraziste wówczas gdy podjęte próby maceracji metodą acetolizy doprowadzą do pełnej ekstrakcji skorupek tych organizmów ze skały. Masowe występowanie otwornic planktonicznych w północnej części oceanu Tethys jest zagadnieniem niezwykle ciekawym, a jednocześnie mało poznanym. W osadach europejskiej części oceanu otwornice planktoniczne występowały u schyłku wczesnego bajosu (doba Humphriesianum), a ich liczniejsze nagromadzenia z tego czasu odnotowano w wielu rejonach, jak n.p. Góry Bakony (Wernli i Görög 1999), Apeniny (rejon Umbria-Marche - Baumgartner 1990) i pieniński pas skałkowy (Tyszka 1999). Skorupki otwornic planktonicznych występowały już bardzo licznie w wapieniach pelagicznych typu ammonitico rosso w środkowej (schyłek bajosu-kelowej) i późnej jurze (Wierzbowski i in. 1999). Wapienie ammonitico rosso były charakterystyczne dla podmorskich wyniesień, a równowiekowe osady basenowe były zdominowane przez osady bogate w radiolarie. Silny rozkwit organizmów planktonicznych podczas środkowej i późnej jury mógł być związany ze zmianami paleogeograficznymi, takimi jak tworzenie się wąskich oceanicznych basenów i długich podmorskich wyniesień, które mogły wymuszać intensywną cyrkulację prądów wznoszących dostarczających do strefy przypowierzchniowej wody dużej ilości składników odżywczych. Wyraźna paleogeograficzna przebudowa europejskiej części Tethys rozpoczęła się w bajosie (Bill i in. 2001; Plašienka 2003); we wczesnym bajosie ukształtował się też śródoceaniczny grzbiet czorsztyński w pienińskim basenie skałkowym (Krobicki i Wierzbowski 2004). Wzmożona aktywność oceanicznych systemów ryftowych mogła zaowocować transgresją i otwarciem szerokich morskich połączeń między oceanem Tethys i morzami epikratonicznymi Europy. Właśnie taki proces mógł spowodować we wczesnym oksfordzie migrację otwornic planktonicznych daleko ku północy, nie tylko do epikratonicznej Polski centralnej, ale nawet znacznie dalej, do Polski północnej, Litwy, południowej Szwecji i południowej Anglii (Grigelis 1958, 1985; Grigelis i Norling 1999; Smoleń 2000; Oxford i in. 2002).

Źródło:

Volumina Jurassica; 2005, 3, 1; 1-10
1896-7876
1731-3708

Pojawia się w:

Volumina Jurassica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:

Integrated stratigraphy of the Middle–Upper Jurassic of the Krížna Nappe, Tatra Mountains

Autorzy:

Jach, R.
Djerić, N.
Goričan, Š.
Řeháková, D.

Powiązania:

https://bibliotekanauki.pl/articles/191333.pdf

Data publikacji:

2014

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

carbon and oxygen isotopes
radiolarians
calcareous dinoflagellates
radiolarites
Krizna nappe
Western Carpathians
Tethys

Opis:

Middle-Upper Jurassic pelagic carbonates and radiolarites were studied in the Krížna Nappe of the Tatra Mountains (Central Western Carpathians, southern Poland and northern Slovakia). A carbon isotope stra- tigraphy of these deposits was combined with biostratigraphy, based on radiolarians, calcareous dinoflagellates and calpionellids. In the High Tatra and Belianske Tatra Mountains, the Bajocian and part of the Bathonian are represented by a thick succession of spotted limestones and grey nodular limestones, while in the Western Tatra Mountains by relatively thin Bositra-crinoidal limestones. These deposits are referable to a deeper basin and a pelagic carbonate platform, respectively. The various carbonate facies are followed by deep-water biosiliceous facies, namely radiolarites and radiolarian-bearing limestones of Late Bathonian-early Late Kimmeridgian age. These facies pass into Upper Kimmeridgian-Lower Tithonian pelagic carbonates with abundant Saccocoma sp. The bulk-carbonate isotope composition of the carbonate-siliceous deposits shows positive and negative S C excursions and shifts in the Early Bajocian, Late Bajocian, Early Bathonian, Late Bathonian, Late Callovian, Middle Oxfordian and Late Kimmeridgian. Additionally, the S13C curves studied show a pronounced increasing trend in the Callovian and a steadily decreasing trend in the Oxfordian-Early Tithonian. These correlate with the trends known from the Tethyan region. The onset of Late Bathonian radiolarite sedimenlalion is marked by a decreasing trend in S13C. Increased S13C values in the Late Callovian, Middle Oxfordian and Late Kimmeridgian (Moluccana Zone) correspond with enhanced radiolarian production. A significant increase in CaCO3 content is recorded just above the Late Callovian S13C excursion, which coincides with a transition from green to variegated radiolarites.

Źródło:

Annales Societatis Geologorum Poloniae; 2014, 84, 1; 1-33
0208-9068

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Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 44.

Tytuł:

Campanian–Maastrichtian foraminiferal stratigraphy and palaeoenvironment of the Lower Tar Member in the Wadi Tar section, Western Sirte Basin (Libya)

Autorzy:

Tshakreen, S. O.
Gasiński, M. A.
Machaniec, E.
Mącznik, A.

Powiązania:

https://bibliotekanauki.pl/articles/191767.pdf

Data publikacji:

2017

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

Southern Tethys
Western Sirte Basin
Lower Tar Member
foraminifera
biostratigraphy
palaeoenvironment
late Campanian–Maastrichtian

Opis:

Upper Campanian–Maastrichtian sections on the western flank of the Hun Graben in the Western Sirte Basin (WSB) are displaying two major type facies based on the foraminiferal assemblages. The first one indicates open-marine to outer-shelf conditions, and is represented by numerous bathy-pelagic planktonic foraminiferal species referable to the Radotruncana calcarata, Globotruncana aegyptiaca and the lower part of the Gansserina gansseri Zone (all late Campanian).The second type facies indicates an inner-shelf environment and is represented in the middle-upper part of the Gansserina gansseri Zone (early Maastrichtian) and Racemiguembelina fructicosa (late Maastrichtian) dominated by epi-pelagic planktonic and large benthic foraminifers. Large benthic foraminiferal index species Siderolites calcitrapoides Lamarck and Omphalocyclus macroporus (Lamarck) occur in abundance by the middle–late Maastrichtian. Correlation between planktonic foraminiferal zonation and large benthic foraminiferal zonation is given. An open-marine to outer-shelf environment passed into shallower marine conditions during the late Campanian–early Maastrichtian to late Maastrichtian, then a slight deepening and again shallowing is noticed.

Źródło:

Annales Societatis Geologorum Poloniae; 2017, 87, 4; 349-362
0208-9068

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Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:

A new family of giant Jurassic–Cretaceous littorinoid gastropods from the northern Tethys shelf

Autorzy:

Harzhauser, M.
Schneider, S.

Powiązania:

https://bibliotekanauki.pl/articles/945827.pdf

Data publikacji:

2014

Wydawca:

Polska Akademia Nauk. Instytut Paleobiologii PAN

Tematy:

mollusca
gastropoda
leviathania
carbonate platform
body size
jurassic–cretaceous
tethys
tithonian
ernstbrunn limestone
austria

Opis:

The giant, up to 40 cm high littorinoid gastropods from the Middle Tithonian to Berriasian carbonates of the Alpine-Carpathian northern Tethys margin are assigned to the genus Leviathania. The genus is distributed from Spain to the Caucasus. Some species formed dense populations in the wide-spread, highly productive lagoonal environments situated on the carbonate platforms of Ernstbrunn (Austria), Mikulov, Štramberk (both Czech Republic), and Nyzhniv (Ukraine). The conspicuous morphology, comprising very large shells with strongly angulated whorls and especially the phaneromphalous umbilicus exclude the traditional attributions of this genus to the families Purpurinidae and Purpuroideidae. Therefore, we establish the new family Leviathaniidae for the type genus Leviathania. The family comprises the largest pre-Cenozoic gastropods, represented by a yet unnamed gigantic Leviathania species from the latest Tithonian or early Berriasian of Ukraine. The gastropods are tentatively assumed to have fed omnivorous, i.e., on a mixed detrital-algal diet, based on comparable population densities as the large modern queen conch Lobatusgigas from the Caribbean Sea.

Źródło:

Acta Palaeontologica Polonica; 2014, 59, 2; 367-378
0567-7920

Pojawia się w:

Acta Palaeontologica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 46.

Tytuł:

Development of the Mid-Polish Troughversus Late Jurassic evolution in the Carpathian Foredeep area

Autorzy:

Matyja, B. A.

Powiązania:

https://bibliotekanauki.pl/articles/2059116.pdf

Data publikacji:

2009

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Mid-Polish Trough
Late Jurassic
northern Tethys shelf
sponge megafacies
Štramberk-type coral reefs

Opis:

Late Jurassic is the key epoch for an idea of the existence of the southeastern segment of the Mid-Polish Trough. New data on the evolution of Upper Jurassic deposits in the Carpathian Foredeep substrate provide information that there is a complete Oxfordian through Valanginian succession in the area of thick Oxfordian and Kimmeridgian deposits, proving the occurrence of the trough. Thickness of the Oxfordian and Kimmeridgian succession is twice to three times smaller than previously assumed. The facies development patterndistinguishes this area from the rest of the Late Jurassic basin. The sponge megafacies ranges up into the lower most Tithonian in this region.Tithonian Štramberk-type reefs occur near the Carpathian thrust front and alongside. The Late Jurassic and earliest Cretaceous facies are latitudinally arranged. Starting from the latest Middle Jurassic, the study area showed strong structural and facies relations to the Tethys do main. The collected data contradict the hypothesis that the Mid-Pol ish Trough continues in the Carpathian Foredeep substrate.

Źródło:

Geological Quarterly; 2009, 53, 1; 49-49
1641-7291

Pojawia się w:

Geological Quarterly

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:

Litostratygrafia i charakterystyka mikropaleontologiczna utworów kredy dolnej w środkowej części przedgórza Karpat
Lithostratigraphy and micropalaeontological characteristic of Lower Lithostratigraphy and micropalaeontological characteristic of Lower

Autorzy:

Urbaniec, A.
Bobrek, L.
Świetlik, B.

Powiązania:

https://bibliotekanauki.pl/articles/2074749.pdf

Data publikacji:

2010

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

kreda późna
przedgórze Karpat
Perytetyda
mikroskamieniałości
formacje litostratygraficzne
Lower Cretaceous
Carpathian Foreland
Peri-Tethys

Opis:

During the Early Cretaceous a central part of the Carpathian Foreland was situated in the Peri-Tethys area. That zone was located on the SW margin of the East European Craton and it was adjacent to the Tethys basins in the south. Impact of those both zoogeographic provinces (the Boreal Sea and the Tethys Ocean) is easily noticeable in assemblages of microfauna. Character of sedimentation in the Early Cretaceous basin of the Carpathian Foreland is connected mainly with changes of the sea-level as well as tectonic activity of this region. The stratigraphy and facies data are based on near two hundreds wells profiles. Detailed sedimentological profiles and photographic documentation of the Upper Jurassic and the Lower Cretaceous deposits from about 50 boreholes were done as well as micropalaeontological and microfacial studies of core samples. The presented work is an attempt of unification and formalization of lithostratigraphic units’ nomenclature. Two boreholes: Zagorzyce-7 andWiewiórka-4 were suggested as stratotype sections of distinguished formations. Jurassic–Cretaceous boundary is probably situated within limits of Ropczyce formation in this area. Three formations have been distinguished in the profile of Lower Cretaceous above Ropczyce formation: Zagorzyce limestone-marl formation (Berriasian age), Dębica marl and organodetritic limestone formation (Valanginian) andWiewiórka limestone formation (Late Valanginian-Hauterivian). The most marked erosion surface is recorded between Zagorzyce and Dębica formations. We suppose that hiatus including a large part of Lower Valanginian profile is connected with that erosion surface. It could be refered to a rapid fall of the sea-level in the Tethys Ocean, noticed inter alia in theWestern Carpathians and the Northern Calcareous Alps. The known existing thickness of the Lower Cretaceous sediments in the middle part of Carpathian Foreland (total of three formations: Zagorzyce fm., Dębica fm. andWiewiórka fm.) rises to 188 m in Zagorzyce-1 well.

Źródło:

Przegląd Geologiczny; 2010, 58, 12; 1161-1175
0033-2151

Pojawia się w:

Przegląd Geologiczny

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:

The Late Eocene evolution of nummulitid foraminifer Spiroclypeus in the Western Tethys

Autorzy:

Less, G
Ozcan, E.

Powiązania:

https://bibliotekanauki.pl/articles/21784.pdf

Data publikacji:

2008

Wydawca:

Polska Akademia Nauk. Instytut Paleobiologii PAN

Tematy:

biometry
nummulitid foraminifer
paleontology
Foraminifera
stratigraphy
Spiroclypeus
Eocene
evolution
Late Eocene
Western Tethys
Nummulitidae

Opis:

Megalospheric forms of Priabonian Spiroclypeus of the Western Tethys were morphometrically investigated. Based on the reduction of the average number of undivided, post−embryonic chambers, the investigated populations are grouped into two successive, phylogenetically linked species, S. sirottii sp. nov. and S. carpaticus. The evolution is also demonstrated by the increase of the number of secondary chamberlets in particular chambers, by the increase of the diameter of the first two whorls and by that of the size of the proloculus, although the latter turned out to be also ecologically controlled. This evolution is supported by the stratigraphic succession of populations in the Mossano section (N Italy) and by the change of accompanying fossils. Lacking in upper Bartonian beds, the first appearance of genus Spiroclypeus seems to be synchronous with the beginning of the late Eocene. The newly described S. sirottii is associated with Heterostegina reticulata mossanensis and orthophragmines containing forms of middle Eocene acme, both marking the lower part of the Priabonian. Meanwhile S. carpaticus co−occurs with H. gracilis and/or with orthophragmines characteristic of the upper part of the Priabonian. We suppose that the Spiroclypeus sirottii–carpaticus lineage is restricted to the Priabonian. Thus, Spiroclypeus sirottii is a zonal marker for the Shallow Benthic Zone (SBZ) 19 (early Priabonian) while S. carpaticusindicates the SBZ 20 (late Priabonian).

Źródło:

Acta Palaeontologica Polonica; 2008, 53, 2
0567-7920

Pojawia się w:

Acta Palaeontologica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:

The middle to Late Eocene evolution of nummulitid foraminifer Heterostegina in the Western Tethys

Autorzy:

Less, G
Ozcan, E.
Papazzoni, C.A.
Stockar, R.

Powiązania:

https://bibliotekanauki.pl/articles/21939.pdf

Data publikacji:

2008

Wydawca:

Polska Akademia Nauk. Instytut Paleobiologii PAN

Tematy:

biometry
Heterostegina
nummulitid foraminifer
paleontology
Foraminifera
stratigraphy
Eocene
evolution
Late Eocene
Western Tethys
Nummulitidae

Opis:

Megalospheric forms of Western Tethyan late Bartonian to late Priabonian involute Heterostegina from numerous localities, marking different ecological conditions, were morphometrically investigated. They belong to three species, H. armenica, H. reticulata, and H. gracilis based on the presence/absence of granulation, on the chamberlet characteristics and on the relative size of proloculus. Within these species a very rapid evolution could be observed in the reduction of the number of operculinid chambers, in the increase of the number of chamberlets and partially in the increase of the proloculus size. This evolution is demonstrated by stratigraphic superpositions in several localities (especially in the Mossano section), and is supported also by the change of co−occurring fossils, starting with the disappearance of large−sized Nummulites, then followed by the appearance of the genus Spiroclypeus and then by the disappearance of orthophragmines of middle Eocene acme. Based on the reduction of operculinid chambers, two chronosubspecies of Heterostegina armenica and seven of H. reticulata are defined biometrically (four of them: H. armenica tigrisensis, H. reticulata tronensis, H. r. hungarica, and H. r. mossanensis are introduced here). This allows to subdivide the Shallow Benthic Zone (SBZ) 18 into three and SBZ 19 into two subzones. The extremely rapid evolution of H. reticulata allows to calibrate larger foraminiferal events around the middle/late Eocene boundary. The extinction of large−sizedNummulitesseems to be heterochronous in the late Bartonian in having migrated eastward, while the first appearance of Spiroclypeus is shown to be synchronous at the base of the Priabonian. The middle/upper Eocene (= Bartonian/Priabonian) boundary is to be placed at the base of the Priabona marls in the Mossano section corresponding to the SBZ 18/19 limit, to the first appearance of genus Spiroclypeus, to that of Nummulites fabianii and of Heterostegina reticulata mossanensis. It falls into the upper part of both the P 15 and NP 18 planktic zones. The Western Tethyan Eocene involute Heterostegina became extinct, apparently with no Oligocene successors.

Źródło:

Acta Palaeontologica Polonica; 2008, 53, 2
0567-7920

Pojawia się w:

Acta Palaeontologica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:

Origin of marls from the Polish Outer Carpathians: lithological and sedimentological aspects

Autorzy:

Górniak, Katarzyna

Powiązania:

https://bibliotekanauki.pl/articles/2086509.pdf

Data publikacji:

2011

Wydawca:

Polskie Towarzystwo Mineralogiczne

Tematy:

marls
Outer Carpathians
lithologic classification
lithofacies
Northern Tethys
sedimentation conditions
tectonics
volcanism
origin of marls

Opis:

Outcrops of marls, occurring within the sandstone-shaly flysch deposits of the Polish part of Outer Carpathians, considered to be locus typicus of these rocks, were described, measured and sampled. Lithologic features of marls, representing 15 complexes of different age and occurring in 15 complexes of various tectonic units, are presented (Fig. 1, 2). The present studies were concerning Jurassic marls from the Silesian Unit (Goleszów Marls), Upper Cretaceous marls from the Skole and Sub-Silesian Units (Siliceous-Fucoid and Węgierka Marls and Węglowka, Frydek, Jasienica and Zegocina Marls respectively), and Eocene-Oligocene marls from the Magura, Fore-Magura and Skole Units (Łącko, Zembrzyce, Budzów, Leluchów and Niwa, as well as Grybów and Sub-Cergowa and Dynów Marls respectively). The former opinions on lithology, age, formal subdivision, sedimentation conditions and genesis of these rocks are discussed (Table 1, 2; Fig. 1). Detailed description of the above mentioned marl-bearing complexes are presented and for each of them the typical lithological features are determined (Tables 3 - 20). The results of profiling are presented against the background of geological studies of the Carpathian marls. The results of lithologic studies are compared to form a classification scheme and are used as the basis of distinguishing genetic types of marls. Moreover, the interpretation of the conditions of sedimentation of these rocks is presented.

Źródło:

Mineralogia; 2011, 42, 4; 165--297
1899-8291
1899-8526

Pojawia się w:

Mineralogia

Dostawca treści:

Biblioteka Nauki

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