The biostratigraphic and palaeoenvironmental significance of Lower Cambrian (Botomian) trilobites from the Ak-Kaya section of the Altai Mountains (southern Siberia, Russia)

Autor:	Nikolay Sennikov, Lauren Pouille, Igor’ V. Korovnikov, Taniel Danelian, Olga Obut
Rok vydání:	2013
Předmět:	Paleontology Sequence (geology) biology Stage (stratigraphy) Section (archaeology) Sedimentary rock Pelagic sediment biology.organism_classification Geology Radiolaria
Zdroj:	Annales de Paléontologie. 99:79-89
ISSN:	0753-3969
Popis:	The presence of one of the oldest records of polycystine Radiolaria in the Lower Cambrian sedimentary sequence of the Ak-Kaya section (Gorny Altai) requires a biostratigraphic dating. The trilobites found recently a few tens of meters below the radiolarian-bearing level belong to Calodiscus resimus Repina, Serrodiscus fossuliferus Repina and Alacephalus aff. contortus Repina; they suggest that this part of the Shashkunar Formation can be correlated with the lower part of the Botomian stage. The absence of eyes in the two former species suggests a mode of life buried in the fine pelagic sediments. Indications of the presence of a strongly developed musculature on the third species point to a palaeoenvironment characterized by a relatively high hydrodynamic regime.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::0d3c9a8a6c6bbb91aca4ecd73b4fb7ab https://doi.org/10.1016/j.annpal.2012.12.001 Zobrazit plný text záznamu Full Text from ScienceDirect