Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "encrusters" wg kryterium: Temat


Wyświetlanie 1-3 z 3
Tytuł:
Morphology and palaeoecology of new, non-marine microconchid tubeworm from Lower Carboniferous (Upper Mississippian) of West Virginia, USA
Autorzy:
Zatoń, M.
Peck, R. L.
Powiązania:
https://bibliotekanauki.pl/articles/191946.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
microconchids
Mississippian
Carboniferous
encrusters
palaeoecology
fresh waters
Opis:
A new species of a non-marine microconchid (Tentaculita) tubeworm, Microconchus hintonensis, from the Lower Carboniferous (Upper Mississippian, Chesterian) of West Virginia, USA, is described. Non-marine microconchids occur abundantly in the deposits of the Bluefield, lower Hinton, Princeton and Bluestone Formations of the Mauch Chunk Group, where they are either associated with land plant remains and bivalve shells, or are preserved loose in the host sediment. The specimens attached to plant remains and bivalve shells, are poorly preserved, but those occurring loose in the deposits are well-preserved in three dimensions. The interpretation pre sented here, is that the loose specimens of Microconchus hintonensis sp. nov. also originally encrusted plants (land plants, algae) and bivalve shells, but became detached after substrate degradation and dissolution. The association of land plant remains, charophyte gyrogonites, bivalves, ostracodes, conchostracans, and fish teeth and scales, and the concomitant lack of strictly marine fossils indicate that the microconchid-bearing deposits of the lower Hinton, Princeton and Bluestone Formations were deposited in fresh-water environments. Microconchus hintonensis sp. nov. is regarded as a highly fecund, opportunistic species that in large numbers colonized every available substrate in its habitat. Its abundance in the deposits investigated indicates that the species was welladapted to the environments it occupied, even during episodes of higher sedimentation rates and/or competition with other soft-bodied encrusters. During such episodes, microconchids were able to grow vertically by uncoiling and elevating their tubes, in order to escape potential burial and/or overgrowth by other encrusters.
Źródło:
Annales Societatis Geologorum Poloniae; 2013, 83, 1; 37-50
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Konkrecje hiatusowe z iłów rudonśnych Wyżyny Krakowsko-Częstochowskiej
Hiatus concretions fromthe ore-bearing clays of the Cracow-Czestochowa Upland (Polish Jura)
Autorzy:
Zatoń, M.
Marynowski, L.
Bzowska, G.
Powiązania:
https://bibliotekanauki.pl/articles/2074474.pdf
Data publikacji:
2006
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
konkrecje hiatusowe
Wyżyna Krakowsko-Częstochowska
hiatus concretions
Middle Jurassic
Cracow-Częstochowa Upland
borers
encrusters
Opis:
Hiatus concretions are arly-diagenetic sedimentary bodies, which in their history of formation, underwent exhumation during sedimentation break and/or erosion of sea-floor. Then they were colonized by various encrusters and borers, before they were buried again. Within Middle Jurassic (Bajocian through Bathonian) clays, hiatus concretions occur in four localities in the Cracow-Częstochowa Upland (south and central Poland): Ogrodzieniec, Bugaj, Mokrsko and Krzyworzeka. Preliminary data about their mineralogy, organic geochemistry and palaeoecology is given. Mineralogical analyses showed, that except dominant high Mg-calcite (up to 87.10% of total carbonates), concretions possess minor amounts of such compounds as quartz, clay minerals (kaolinite and illite), pyrite, siderite or Mg-kutnahorite. However, high differences are observed between total organic carbon contents of concretions (TOC=0.46%) and surrounded clays (TOC = 2.16%), but their molecular composition is similar. Most of identified biomarkers are of terrestrial origin. In clay lithology, the hiatus concretions are the only sedimentary bodies that clearly mark the sedimentation pauses (hiatuses). In the investigated area, they form more or less continuous horizons. The concretions are calcitic, possessing various encrusting fauna such as bryozoans, oysters and oyster-like bivalves, serpulids, solitary corals and foraminifers. They often post-date the borings, belonging to such ichnogenera as Gastrochaenolites, Trypanites and Entobia. Some of the nodules show distinct transition from firmground (characterized by the presence of Glossifungites ichnocoenosis) to hardground (presence of Trypanites ichnocoenosis), pointing to the fact, that they formed at, or very close to, the sediment-water interface. Some concretions, like those from Bugaj and Mokrsko, are characterized by their high diversity of hard bottom communities. Those concretions are also irregular in shape; others, like those from Ogrodzieniec and Krzyworzeka, possess lower diversity. The concretions from Krzyworzeka are especially dominated by the borers, while the encrusters are sparse and not diverse. Those nodules that are wide and flat tend to be more bored on one surface only, while those that are more roundish, are bored on both sides more evenly. The degree of diversity is probably correlated with physical disturbance, causing the rolling and overturning of the exhumed concretions in the littoral zone. On the other hand, the overall diversity could be lowered due to destructive abrasion either of the shallowest borings, echinoid/gastropod scratch marks and shells of nestling bivalves, as well as more delicate epilithozoans.
Źródło:
Przegląd Geologiczny; 2006, 54, 2; 131-138
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Depositional environments, facies and diagenesis of the Upper Jurassic–Lower Cretaceous carbonate deposits of the Buila-Vânturariþa Massif, Southern Carpathians (Romania)
Autorzy:
Pleş, G.
Bucur, I. I.
Săsăran, E.
Powiązania:
https://bibliotekanauki.pl/articles/191844.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Carbonate platforms
reefs
microfacies
micro-encrusters
carbonate diagenesis
Upper Jurassic
lowermost Cretaceous
Southern Carpathians
Romania
Opis:
The Buila-Vânturariţa Massif consists of massive Upper Jurassic reef limestones (Kimmeridgian–Tithonian) and Lower Cretaceous (Berriasian–Valanginian, and Barremian–?Lower Aptian) deposits. Besides corals and stromatoporoids, a wide range of micro-encrusters and microbialites has contributed to their development. In this study, the authors describe briefly and interpret the main facies associations and present the microfossil assemblages that are important for age determination. The distribution of facies associations, corroborated with the micropalaeontological content and early diagenetic features, indicate different depositional environments. The carbonate successions show the evolution of the Late Jurassic–Early Cretaceous depositional environments from slope and reef-front to internal-platform sedimentary settings, including peritidal environments in the lowermost Cretaceous. Early diagenesis, represented by synsedimentary cementation in the form of micritization (including cement crusts in the reef microframework), followed by dissolution, cementation and dolomitization in a meteoric regime, and void-filling late cementation during the burial stage.
Źródło:
Annales Societatis Geologorum Poloniae; 2016, 86, 2; 165-183
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies