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The Paleogene marine strata in southern Tibet are well developed and rich in foraminifera and other marine fossils. Based on the study of macroforaminifera taxonomy and Stratigraphy in the West Tethys domain (mainly the Mediterranean region), western scholars established the Paleocene Eocene macroforaminifera biostratigraphy in 1998. Compared with Tibet in the East Tethys domain, the development of macroforaminifera in the Paleocene in the Mediterranean region is relatively poor. Therefore, the accuracy of biostratigraphy based on sittis foraminifera is low. In this study, detailed profile survey and high-density sample collection of lower Paleogene carbonate sedimentary strata in guru area, southern Tibet are carried out to supplement and improve the biostratigraphy of macroforaminifera in southern Tibet on the basis of macroforaminiferal taxonomy research; Based on biostratigraphy and carbon isotope stratigraphy, a high-resolution chronostratigraphic framework is established.

A total of 7 profiles were measured in this study, and the profiles are located between 89 ° 11 ′ ~ 89 ° 13 ′ E and 28 ° 3 ′ ~ 28 ° 7 ′ n; The elevation range is 4643 ~ 5380 M. Based on the observation of rock slices in the laboratory, the age of the measured strata is preliminarily judged. P2 section is a limestone sequence overlying the late Cretaceous strata, representing the earliest Paleocene sedimentation in the study area; P1 section is a set of very thick limestone deposits of lower Paleocene; Section E2 is the top of Paleocene, close to the Paleocene / Eocene boundary; The ages of sections E1, E3, E3s and E4 are roughly early Eocene; The grayish green marl and red shale at the top of section E4 represent the latest marine strata in the study area.

We plan to conduct detailed taxonomic and stratigraphic studies on foraminifera in these sections to establish high-resolution large foraminifera biostratigraphy; At the same time, we also need to analyze the changes in composition and abundance of macroforaminifera, and further explore the evolution process of macroforaminifera in early Paleogene. For the sandstone strata in the section, we need to conduct detrital zircon U-Pb isotope analysis, the obtained age and biostratigraphic data confirm each other, and further explore the paleogeographic evolution process under the influence of India Eurasia collision.