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Tytuł:
Construction of ichnogeneric names
Autorzy:
Rindsberg, A. K.
Powiązania:
https://bibliotekanauki.pl/articles/191214.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
ichnology
trace fossils
ichnotaxonomy
terminology
Opis:
Ichnologists have over used the root ichn- “trace”, employing it in new terms and new ichnogenera alike, to the point where it can be difficult to express one self clearly without using it several times in one sentence. The root derives from Ancient iχνος (ichnos), which means “foot print” or “track”, or by extension a “trace”, any sign of an animal’s activity. Perhaps it is time to explore the use of other roots to create new ichnologic terms and genera. Alternative Latin and Greek roots are given here, as well as ad vice on how to construct new ichnogenera in a technically correct and aesthetically pleasing manner.
Źródło:
Annales Societatis Geologorum Poloniae; 2015, 85, 3; 529-549
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of fossils on diagenetically controlled reservoir quality : the Zechstein Brońsko Reef
Autorzy:
Fheed, Adam
Powiązania:
https://bibliotekanauki.pl/articles/191256.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
carbonates
dissolution channels
diagenesis
fossils
porosity
Opis:
Although the sedimentation and diagenesis of the Polish Zechstein Limestone strata (Ca1, Permian) already have been investigated, relatively little has been done to resolve their petrophysical potential. Therefore, the gap between sedimentological and petrophysical studies was bridged through an integrated analysis of geological and geophysical data. The results of core description, polarized-light microscopy, well log interpretations and laboratory measurements on core samples were combined with previously published nuclear magnetic resonance (NMR) and X-ray microtomography (μCT) data, especially helpful in the recognition of pore geometry. The Ca1 strata of the Brońsko-1 and Brońsko-2 wells, located on the Zechstein Brońsko Reef (West Poland), were studied to determine the influence of fossils on porosity and permeability. It was concluded that greater diversification of the original biota led to an increase in porosity and variation in pore geometry. While encrusting organisms such as foraminifers promoted the development of channel and fracture porosity, the dissolution of the primarily aragonitic bivalve and gastropod shells and the shells of terebratulid brachiopods often gave rise to the formation of cavernous and mouldic porosity. The channels appear to be most common in the bryozoan-foraminifer biofacies, representing a shallowing of the depositional environment. Caverns, in turn, corresponded to the organisms of the brachiopod-bryozoan and the lightly karstified bivalve-gastropod biofacies, both of which probably experienced the influence of sabkha conditions, leading to a general decrease in porosity. The bryozoan zoecia tended to enhance both primary intraparticle voids, and after their dissolution, secondary intraparticle pores, which showed limited connectivity in the high-energy Acanthocladia biofacies, where considerable fragmentation of fossils took place, hence decreasing the permeability. Anhydrite cementation was found to be the most pronounced factor controlling porosity destruction, while dolomitization enhanced it significantly, especially for the stromatolitic biofacies, where small, unconnected vugs were formed owing to this process. The permeability is typically below 100 mD, and this is caused by the rich diagenetic history of the reef, that recorded marine, sabkha-related and burial cementation, now represented by the different fabrics of anhydrite, calcite, and dolomite.
Źródło:
Annales Societatis Geologorum Poloniae; 2019, 89, 1; 47-81
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioerosional ichnotaxa and the fossilization barrier
Autorzy:
Bromley, R. G.
Nielsen, K. S. S.
Powiązania:
https://bibliotekanauki.pl/articles/191978.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Fossilized
unfossilized
bioerosion
trace fossils
microborings
Opis:
For the establishment of a new ichnogenus or ichnospecies, the type material shall be fossil, not unfossilized material. This is not always possible, because the transition between the two states, the fossilization barrier, is extremely vague defined. In most fossil material, this is not a problem. However, in the case of bioerosion structures (borings, rasping traces, attachment scars in hard substrates), the problem is serious. For example, when does a sponge boring in an oyster shell be come fossilized? The question arises when Recent and sub-Recent materials are considered. Two examples are discussed. (1) Microborings are described and named in foraminifera dredged from the sea floor. In this material, it is not possible to distinguish between “fossilized” and “unfossilized” foraminifera. Bioturbation and other processes may have mixed recently dead, Pleistocene and older foraminifera in the sea-floor sediments. (2) Small, characteristic borings are made by slipper limpets in pagurized gastropod shells. The structures would constitute a new ichnospecies of Oichnus, but these borings have not been found in “fossilized material” and the borings therefore remain nameless. Because bioerosion structures constitute “ready-made fossils”, it is suggested that the onset of fossilization be equated with the death of the bioeroding tracemaker.
Źródło:
Annales Societatis Geologorum Poloniae; 2015, 85, 3; 453-455
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ichnology of Upper Cretaceous–lower Palaeogene deep-sea deposits in the Haymana Basin of Central Anatolia
Autorzy:
Demircan, Huriye
Görmüş, Muhittin
Powiązania:
https://bibliotekanauki.pl/articles/1836251.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
trace fossils
benthic foraminifera
Campanian
Paleocene
Turkey
Opis:
Upper Cretaceous to lower Palaeogene carbonate and siliciclastic deposits that crop out widely in the Haymana and Polatlı districts (Ankara Province) of the Haymana Basin (Central Anatolia) are rich in larger benthic foraminifera, various macrofossils and ichnofossils. The ichnofossils of the Haymana and Yeşilyurt formations were studied at five localities. The Upper Cretaceous siliciclastics of the Haymana Formation contain moderately diverse trace fossils, belonging to the deep-sea Nereites ichnofacies. The Paleocene siliciclastic and carbonate deposits of the Yeşilyurt Formation comprise similar trace fossils, which do not show significant changes in comparison to the Haymana Formation. This indicates that the K-Pg boundary extinction event did not affect the ichnofauna with any longer consequences. The Upper Cretaceous coarser, siliciclastic deposits of the Haymana and Beyobası formations are rich in shallow-marine, larger benthic foraminifera, including species of Orbitoides, Omphalocyclus, Siderolites, Hellenocyclina, and Loftusia, whereas fine siliciclastic deposits contain abundant planktonic, open-marine foraminifera, such as Globotruncana and Heterohelix. Palaeogene siliciclastic to carbonate deposits of the Kartal, Yeşilyurt and Çaldağ formations are rich in the larger, benthic foraminifera Nummulites, Discocyclina, Assilina and Alveolina. The larger foraminifers have been redeposited from nearby, shallow-marine parts of the basin.
Źródło:
Annales Societatis Geologorum Poloniae; 2020, 90, 4; 463-493
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First report on swimming trace fossils of fish from the Upper Permian and Lower Triassic of the Dolomites (Italy)
Autorzy:
Ronchi, A.
Santi, G.
Marchetti, L.
Bernardi, M.
Gianolla, P.
Powiązania:
https://bibliotekanauki.pl/articles/191698.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Trace fossils
Undichna
Permian
Triassic
northern Italy
Opis:
In the Upper Permian continental to marginal-marine succession of the Southern Alps (Dolomites, north Italy), the ichnological record consists of diverse vertebrate footprints and non-diverse invertebrate trace fossils, mainly occurring in the “Bletterbach ichnoassociation” of the Val Gardena Sandstone Formation. After the Permian-Triassic Boundary event, vertebrate ichnoassociations are scarce until the Middle Triassic (Anisian), whereas the uppermost Permian-Lower Triassic Werfen Formation preserves a rich invertebrate trace-fossil record. To date, fish body and trace fossils (Undichna) are very rare in the pre- and post-extinction deposits of the Dolomites; only Undichna gosiutensis Gibert, 2001 was identified in the “Voltago Conglomerate” (Middle Anisian), whereas some unidentified fossil fish casts were found in the Permian Val Gardena Sandstone and some fish remains in the overlying Werfen Formation. Recently, for the first time, fish trails have been discovered in the Val Gardena Sandstone (Lopingian) and in the Werfen Formation (Campil member, Early Triassic, Smithian). Val Gardena Sandstone yielded Undichna cf. quina Trewin, 2000 and U. bina Anderson, 1976 and these represent the oldest fish trails found in the Southern Alps so far. Conversely, the specimens found in the Werfen Formation can be assigned to Undichna cf. britannica Higgs, 1988. They represent the oldest Mesozoic record of fish trace fossils in northern Italy and one of the few records of Undichna from marine environments. These trace fossils are consistent with the fossil association found in the two formations and reflect fish swimming activity in different environments: in very shallow, calm, brackish distal-floodplain to marginal-marine environments in the Late Permian, in association with abundant and diverse tetrapod tracks, and non-diverse invertebrate trace fossils, and in inter- to subtidal calm, shallow, marine environments in the Early Triassic, together with abundant, but not diverse invertebrate trace fossils.
Źródło:
Annales Societatis Geologorum Poloniae; 2018, 88, 2; 111-125
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ichnotaxonomy as a science
Autorzy:
Rindsberg, A. K.
Powiązania:
https://bibliotekanauki.pl/articles/191834.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
taxonomy
ichnotaxobases
trace fossils
ichnology
standardized classification
Opis:
If ichnotaxonomy is to be scientific, then its results must be repeatable. While some ichnotaxa are identified consistently, others are not, suggesting that ichnotaxonomy is not a mature science. When researchers disagree on the identification of a specimen, it suggests that closer examination is needed: an intermediate stage in the scientific method. But when ichnologists publish different names for the same trace fossils, multiple trials of classification have yielded different results, suggesting a failure of the hypotheses that led to the names. The burgeoning of invertebrate ichnology from the 1960s onward was made possible by demonstrating its utility to the petroleum industry; in part, this was accomplished by simplifying the ichnotaxonomy of common trace fossils to the point where a specialist was not required to make use of them in sedimentology and stratigraphy. The biological aspect of trace fossils, albeit of great interest, was downplayed in favour of a severely geometric approach. Ironically, this has had the effect of obscuring basic relationships of trace fossils and their palaeoenvironments that could be of great use to sedimentologists. Previous researchers have emphasized the value of a uniform approach in ichnotaxonomy. To accomplish this, ichnologists should take inspiration from the taxonomy of body fossils. Making ichnotaxonomy more replicable will take time and effort among investigators. In the long run, this can be accomplished by a holistic approach that includes close observation of trace fossils, standardized procedures of description and diagnosis, reinvestigation of type material, attention to bioprint (morphological traits that reveal the anatomical and ethological characteristics of the tracemakers; Rindsberg and Kopaska-Merkel, 2005), avoidance of taphonomic and human bias, and above all, cooperation.
Źródło:
Annales Societatis Geologorum Poloniae; 2018, 88, 2; 91-110
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A mixed assemblage of deep-sea and shelf trace fossils from the Lower Cretaceous (Valanginian) Kamchia Formation in the Troyan region, central Fore-Balkan, Bulgaria
Autorzy:
Uchman, A.
Tchoumatchenco, P.
Powiązania:
https://bibliotekanauki.pl/articles/973639.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
trace fossils
ichnology
Lower Cretaceous
Fore-Balkan
Bulgaria
Opis:
Trace fossils collected from the best outcrop of the Kamchia Formation have been analysed. There are thirteen ichnotaxa (Curvolithus simplex, Gyrochorte isp., ?Helminthoidichnites tenuis, Multina minima [second occurrence], Palaeophycus tubularis, ?Palaeophycus isp., Phycodes bilix, Phycosiphon incertum, Planolites cf. reinecki, Spongeliomorpha ?chevronensis, Squamodictyon tectiforme, Thalassinoides suevicus, Zoophycos isp.) representing different ethologic, toponomic and preservational types, and produced at different depths in the sediment. The ichnoassemblage contains a mixture of forms typical of flysch (Squamodictyon) and shelf deposits (Curvolithus, Gyrochorte). Probably, sediments of the Kamchia Formation were deposited in an offshore or deeper basin with storm deposition of sand beds and background marly sedimentation. It is possible that storm currents transported trace makers of the shelf trace fossils to the deeper sea. It is not excluded that the trace maker of Gyrochorte migrated to the deep-sea after the Jurassic. However, the simplest explanation is that the Kamchia ichnofauna represents an ecological transition between shelf and slope communities.
Źródło:
Annales Societatis Geologorum Poloniae; 2003, 73, No 1; 27-34
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New ichnotaxa of vertebrate burrows from the Salt Wash Member, Upper Jurassic Morrison Formation, south-eastern Utah (USA)
Autorzy:
Raisanen, D. C. W.
Hasiotis, S. T.
Powiązania:
https://bibliotekanauki.pl/articles/191391.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
ichnofossils
continental
palaeosols
fossorial
trace fossils
domichnia
polychresichnia
Opis:
Large-diameter burrows in pedogenically modified floodplain deposits in the Salt Wash Member, Upper Jurassic Morrison Formation, southeast Utah, U.S.A., are interpreted to have been constructed by mammals. They are distinguished as Daimonelix martini isp. nov., which exhibits a helical shaft down to a horizontal tunnel with a mean depth of 71.4 cm from the inferred palaeosurface. The mean path length of the shaft is 99.4 cm; mean dip of the whorls is 39°. The mean tunnel length is 42.3 cm. Shafts and tunnels are oval or elliptical in cross section with the horizontal diameter slightly larger than the vertical (ratio of -1.26:1); the shaft averages 9.2 cm wide and 7.3 cm tall; the tunnel averages 10.7 cm wide and 10.7 cm tall. The tracemaker was likely a fossorial mammal that used the burrow as a den to shelter when not foraging above ground; the burrows are domichnia. The other from the same member is Fractisemita henrii igen. nov. et isp. nov., a network of interconnected shafts and tunnels; shaft and tunnel segments are straight, curved, or helical. The segments are at angles of 0-89°; mean length of a section is 30.7 cm. The cross sections of all elements are oval or elliptical; the mean width is 6.3 cm and the mean height is 4.9 cm (ratio of -1.29:1). The burrows are interpreted as the work of a social mammal and represent multiple tracemaker behaviours: protection, denning, foraging, and possibly food storage. The burrows are polychresichnia. Surficial morphologic features preserved on the burrow walls of both types are interpreted as scratches made by the tracemaker claws and/or teeth. The burrows reveal the actions of small vertebrates not recorded by body fossils showing potential partitioning of the environment and availability of resources for small vertebrates.
Źródło:
Annales Societatis Geologorum Poloniae; 2018, 88, 2; 181-202
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan
Autorzy:
Warchoł, M.
Leszczyński, S.
Powiązania:
https://bibliotekanauki.pl/articles/191469.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Tien Shan
Kyrgyzstan
Silurian-Devonian
turbidites
trace fossils
Opis:
The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian–Devonian age. They resemble deposits of overbank areas and depositional lobes of deep sea fans, and display common trace fossils particularly on lower surfaces of sandstone beds. Sixteen ichnotaxa representing four morphological groups have been distinguished. The trace fossil assemblages suggest their affiliation to the Nereites ichnofacies. Various branched, preturbidite forms predominate in both examined units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor.
Źródło:
Annales Societatis Geologorum Poloniae; 2009, 79, No 2; 1-11
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan
Autorzy:
Warchoł, M.
Leszczyński, S.
Powiązania:
https://bibliotekanauki.pl/articles/191868.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Tien Shan
Kyrgyzstan
Silurian-Devonian
turbidites
trace fossils
Opis:
The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian-Devonian age. They resemble deposits of overbank areas and depositional lobes of deep sea fans, and display common trace fossils particularly on lower surfaces of sandstone beds. Sixteen ichnotaxa representing four morphological groups have been distinguished. The trace fossil assemblages suggest their affiliation to the Nereites ichnofacies. Various branched, preturbidite forms predominate in both examined units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor.
Źródło:
Annales Societatis Geologorum Poloniae; 2009, 79, No 1; 1-11
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ichnofossil assemblages and palaeosols of the Upper Triassic Chinle Formation, south-eastern Utah (USA): Implications for depositional controls and palaeoclimate
Autorzy:
Fischer, J. S.
Hasiotis, S. T.
Powiązania:
https://bibliotekanauki.pl/articles/973435.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
continental
trace fossils
groundwater profile
ichnology
ichnocoenoses
ichnopedofacies
Mesozoic
Opis:
The Upper Triassic Chinle Formation in the Stevens Canyon area in south-eastern Utah represents fluvial, palustrine, and lacustrine strata deposited in a continental back-arc basin on the western edge of Pangea. Previous investigations interpreted a megamonsoonal climate with increasing aridity for the Colorado Plateau towards the end of the Triassic. In this study, we systematically integrate ichnological and pedological features of the Chinle Formation into ichnopedofacies to interpret palaeoenvironmental and palaeoclimatic variations in the north-eastern part of the Chinle Basin. Seventeen ichnofossil morphotypes and six palaeosol orders are combined into twelve ichnopedofacies, whose development was controlled by autocyclic and allocyclic processes and hydrology. Ichnopedofacies are used to estimate palaeoprecipitation in conjunction with appropriate modern analogue latitudinal and geographic settings. In the north-east Chinle Basin, annual precipitation was -1100-1300 mm in the Petrified Forest Member. Precipitation levels were >1300 mm/yr at the base of the lower Owl Rock Member, decreased to -700-1100 mm/yr, and then to -400-700 mm/yr. Two drying upward cycles from -1100 mm/yr to -700 mm/yr occurred in the middle and upper part of the Owl Rock Member. In the overlying Church Rock Member, precipitation decreased from -400 mm/yr at the base of the unit to -25-325 mm/yr at the end of Chinle Formation deposition. Ichnopedofacies indicate monsoonal conditions persisted until the end of the Triassic with decreasing precipitation that resulted from the northward migration of Pangea. Ichnopedofacies in the northeast Chinle Basin indicate both long-term drying of climate and short-term, wet-dry fluctuations.
Źródło:
Annales Societatis Geologorum Poloniae; 2018, 88, 2; 127- 162
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Disappeared almost without a trace : Taphonomic pathways and the recognition of hidden bioturbation events in Eocene storm deposits (Paují Formation, Lake Maracaibo, Venezuela)
Autorzy:
Buatois, L. A.
Delgado, M.
Mángano, M. G.
Powiązania:
https://bibliotekanauki.pl/articles/191974.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
trace fossils
ichnofabric
taphonomic pathways
tempestites
shallow marine
Eocene
Opis:
Shallow-marine deposits, included in the “Basal Sands” of the Eocene Paují Formation of the Maracaibo Basin in western Venezuela, record deposition in fore shore to lower off shore settings. These deposits are stacked in coarsening-upward parasequences that reflect variable intensities and frequencies of storms. Of particular interest are sharp-based, amalgamated, hummocky cross-stratified and rippled, very fine-grained sandstone beds, observed in the core MOT-X from the Motatán Field. These beds record storm deposition, under purely oscillatory to combined flows in an offshore-transition setting. The amalgamated nature of the sand stone interval indicates repeated erosion, due to multiple storm events. The ichnofabrics in these tempestites result from a distinctive taphonomic pathway, reflecting the interplay between bioturbation events and storm erosion and deposition. The storm-related trace-fossil suite is represented by Diplocraterion parallelum and local occurrences of Palaeophycus tubularis, Bergaueria isp. and Thalassinoides isp., which is consistent with the relatively high energy of formation of these deposits. Fair-weather deposits are absent from the sand stone interval. However, high densities of Chondrites isp. are present in the infills of Diplocraterion parallelum and, more rarely, Thalassinoides isp. providing the sole evidence of the establishment of a resident fauna during inter-storm intervals. Deposits containing the fair-weather suites were erosionally removed during the subsequent storm. The deep-tier emplacement of Chondrites and the ability of its producer to rework other biogenic structures favour preservation, allowing recognition of a “hidden” bioturbation event that otherwise might have remained undetected.
Źródło:
Annales Societatis Geologorum Poloniae; 2015, 85, 3; 473-479
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace fossils from the Upper Cretaceous Capacete Formation, Sanfranciscana Basin, Central Brazil
Autorzy:
Sedorko, Daniel
Alessandretti, Luciano
Warren, Lucas Veríssimo
Verde, Mariano
Rangel, Caio César
Ramos, Kimberly Silva
Netto, Renata Guimarães
Powiązania:
https://bibliotekanauki.pl/articles/1836263.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
meandering fluvial system
insects
continental trace fossils
Scoyenia ichnofacies
Opis:
The Upper Cretaceous Capacete Formation, from the intracratonic Sanfranciscana Basin, central Brazil, consists of epiclastic sediments with a significant aeolian contribution. This unit has been traditionally interpreted as deposited by alluvial fans distally grading to braided rivers in an arid- to semiarid climate within the central part of southwestern Gondwana. Locally, some expositions with wide lateral extension show architectural elements indicative of deposition in meandering rivers, such as floodplain fines (FF) interbedded with crevasse splay (CR), lateral-accretion macroforms (LA), and channels (CH). Bioturbation within the meandering fluvial deposits is commonly associated with the floodplain element, mainly occurring in fine-grained sandstone and mudstone. The lateral-accretion elements and channel deposits are barren of trace fossils. Sandstone with climbing ripples (Sr) from the element CR show low bioturbation of meniscate trace fossils assigned to Taenidium, Beaconites, and Scoyenia ichnogenera. Simple vertical and horizontal burrows identified as Skolithos and Palaeophycus occur associated with Taenidium and Camborygma in sandstone facies (Sr, St and Sh), as well as rhizoliths, representing the Scoyenia ichnofacies. The predominance of trace fossils related to the FF and CR architectural elements attests to the colonization mostly by insects in episodic and vegetated flood plains of the meandering river system from the Capacete Formation. Thus, despite the primarily arid to semiarid conditions interpreted for the inner parts of the newly formed South American continent during the Upper Cretaceous, our new data support deposition under humid conditions in some intervals of the Capacete Formation from the Sanfranciscana Basin.
Źródło:
Annales Societatis Geologorum Poloniae; 2020, 90, 3; 247-260
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace fossils from the Mississippian of the Piaskowa Góra section (the Intra-Sudetic Basin, SW Poland)
Autorzy:
Muszer, Jolanta
Powiązania:
https://bibliotekanauki.pl/articles/1836353.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Trace fossils
Szczawno Formation
Intra-Sudetic Basin
lower Serpukhovian
Opis:
Eight ichnotaxa and enigmatic tubular forms were discovered and described for the first time from clastic deposits (the Culm facies) of the uppermost part of the Szczawno Formation (upper Mississippian) from in the Piaskowa Góra section in the northern part of the Intra-Sudetic Basin near Wałbrzych. The trace fossils are represented mostly by pascichnia and less numerous domichnia, fodinichnia and repichnia. Psammichnites plummeri and numerous Phycosiphon isp. are the most common ichnotaxa. They are accompanied by Archaeonassa fossulata, Beaconites cf. capronus, Curvolithus multiplex, Dictyodora liebeana, Palaeophycus isp., and Planolites isp. D. liebeana is described for the first time from the lower Serpukhovian. Most components of the ichnoassem-blage are typical of the Cruziana ichnofacies, but the co-occurrence of Dictyodora and Phycosiphon could indicate a transition to deeper environmental settings (the Zoophycos ichnofacies). The lithological features as well as the accompanying trace fossils, wrinkle structures and floral remains of Archaeocalamites indicate rapid sedimentation, alternating with more tranquil periods of sedimentation, in an intermediate environment between the lower offshore (the distal Cruziana ichnofacies) and the fan-delta slope (below the wave base, the Zoophycos ichnofacies). The studied trace fossils and palynological data indicate that marine conditions in the Wałbrzych area in the Mississippian prevailed locally until the early Sepukhovian.
Źródło:
Annales Societatis Geologorum Poloniae; 2020, 90, 2; 195-213
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pioneer colonization, evidenced by Rhizocorallium in the Middle Triassic of Poland
Autorzy:
Stachacz, Michał
Powiązania:
https://bibliotekanauki.pl/articles/27311290.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
trace fossils
bioturbation
Muschelkalk
Ichnotaxonomy
palaeoecology
post-extinction biota recovery
Opis:
A large collection of the trace fossil Rhizocorallium from the Middle Triassic of the Polish part of the Germanic Basin (Peri-Tethys) is analysed and their ichnotaxonomical classification presented. Special attention is given to the deep form of Rhizocorallium with a vertical retrusive spreite, filled with faecal pellets, with detailed documentation of this structure, based on isolated specimens and serial sections. This analysis also reveals ∩-shaped and deep, protrusive structures. A former interpretation of Rhizocorallium as a rapidly formed fugichnion is not followed here; instead, an interpretation of the trace fossil as a complex fodinichnion is proposed. Scavengers and their relation to crinoid meadows, as well as predators, are indicated as potential tracemakers of some Rhizocorallium. Although Rhizocorallium is common throughout the Middle Triassic, unusual forms and the domination of substrates by Rhizocorallium in general mostly occur in the transgressive system of the lowermost Muschelkalk, and in regressive, marginal facies of the lower Keuper. Such a distribution of unusual forms of Rhizocorallium is interpreted as representing opportunistic, pioneer burrow assemblages that developed during the long-term benthic recovery after the P-T crisis, or in unfavourable conditions generally. Moreover, dynamic conditions with mixed clastic-carbonate sedimentation and rapidly varying salinity promoted smooth transitions from Rhizocorallium to Diplocraterion. Similar successions of dominant trace-fossil assemblages, of comparable sizes, occur in many sections around the world and demonstrate the record of slow recovery that continued through the Middle Triassic. The illustrated record of evolution of the Middle Triassic Rhizocorallium assemblages in Poland documents the last two stages of benthos recovery after the P-T boundary. A similar situation is observed around the world and, in many cases, great abundance of Rhizocorallium seems to be an indication of pioneer burrowing in dynamic, unfavourable environments.
Źródło:
Annales Societatis Geologorum Poloniae; 2023, 93, 4; 363--379
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł

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