气候变化领域集成服务门户(CCPortal): Upper Jurassic to Lower Cretaceous benthic foraminifera from South Tibet (Tethyan Himalayas): systematic, biostratigraphic, and palaeoecologic implications

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DOI	10.1016/j.revmic.2023.100713
	Upper Jurassic to Lower Cretaceous benthic foraminifera from South Tibet (Tethyan Himalayas): systematic, biostratigraphic, and palaeoecologic implications
	Colpaert, Clementine Peggy Anne-Marie; Li, Gang
发表日期	2023
ISSN	0035-1598
卷号	78
英文摘要	The present study represents the first attempt to described foraminiferal fauna of the Gucuo Locality and is among the first work to illustrate the Upper Jurassic to Lower Cretaceous benthic foraminifers of South Tibet. The material consists in a combination of unpublished data on the Gucuo Section and published data on the Gyangze; Weimei, and Bandingsi sections. A total of 239 specimens have been currently recorded in the Upper Jurassic to Lower Cretaceous Menkadun and Gucuo formations of the Gucuo locality. To facilitate further researches on foraminifers from the Tethyan Himalayas, a total of 59 species from 38 genera have currently been repertory and described. Among the recorded specimens, a few species are significant biostratigraphic markers used to identify and constrain the age of four foraminiferal assemblages. The Textularia aff. haeusleri assemblage contains a few numbers of agglutinated species very similar to the one described in the Oxfordian to Kimmeridgian Nupra Formation of the Thakkola Region. The Tithonian Trochammina quinqueloba assemblage is a widespread biostratigraphic horizon recorded in both southern and northern parts of South Tibet, as well as in the Indian and the Proto-Atlantic oceans. The Berriasian to Valanginian Trochammina abrupta assemblage contains typical Early Cretaceous foraminifers. It confirms the Jurassic/Cretaceous boundary should be delineated at the base of the shale Unit of the Gucuo Formation, although it was previously attributed to the base of the volcaniclastic sandstone units using ammonite data. This latest being currently associated to the Valanginian to Hauterivian Ammobaculites crepinae-Textularia bettenstaedti foraminiferal assemblage. A palaeoecological reconstruction along a southwest to northeast transect of South Tibet, Himalayas, is proposed to understand the composition and dynamic of foraminiferal assemblages along with palaeoenvironmental changes. The morphogroup approach has been selected as the best methods to illustrate both sea-level and oxic changes. The northern tectonic zone of South Tibet is associated with the abundance of deep-water agglutinated foraminifers, which suggests a deep environment beyond the shelf break. The southern tectonic zone of South Tibet is rich in typical species of shallow environment and was located on the neritic shelf. The morphogroup analysis reveals localized, periodic disaerobic conditions on the sea-floor. The Jurassic to Cretaceous Boundary interval was associated with a drop of the sea-level, whereas the rise in diversity and abundance of marginal-sea taxa during the Valanginian to Hauterivian times underline a higher sea-level and a pulse in the development of epeiric seas in the southern part of South Tibet.
关键词	Mesozoic Micropalaeontology Tethys Ocean Gondwana Biozonation Foraminifera
英文关键词	PREBETIC ZONE; BETIC CORDILLERA; DALAZI FORMATION; BASIN; STRATIGRAPHY; ASSEMBLAGES; WESTERN; SUCCESSION; EVOLUTION; COLLISION
WOS研究方向	Paleontology
WOS记录号	WOS:001005402500001
来源期刊	REVUE DE MICROPALEONTOLOGIE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283002
作者单位	Chinese Academy of Sciences; Russian Academy of Sciences; Trofimuk Institute of Petroleum Geology & Geophysics
推荐引用方式 GB/T 7714	Colpaert, Clementine Peggy Anne-Marie,Li, Gang. Upper Jurassic to Lower Cretaceous benthic foraminifera from South Tibet (Tethyan Himalayas): systematic, biostratigraphic, and palaeoecologic implications[J],2023,78.
APA	Colpaert, Clementine Peggy Anne-Marie,&Li, Gang.(2023).Upper Jurassic to Lower Cretaceous benthic foraminifera from South Tibet (Tethyan Himalayas): systematic, biostratigraphic, and palaeoecologic implications.REVUE DE MICROPALEONTOLOGIE,78.
MLA	Colpaert, Clementine Peggy Anne-Marie,et al."Upper Jurassic to Lower Cretaceous benthic foraminifera from South Tibet (Tethyan Himalayas): systematic, biostratigraphic, and palaeoecologic implications".REVUE DE MICROPALEONTOLOGIE 78(2023).