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Yadong area was located at the residual basin of the Neotethys during Paleogene,which developes a set of youngest marine deposition of the Tethyan Himalayas,and therefore the biostratigraphic data from Tingri-Gamba-Yadong area are essential to constrain the age of the India-Asia collision.Planktic foraminifera study is usually considered to be one of the most important methods to determine the age of the Meso-Cenozoic marine sediments,and thus can be used to define the age of the latest sediment of Tethyan Himalayas,which can well constraint the age of the India-Asia collision.A detailed investigation on planktic foraminfer was firstly provided for the newly discovered marine horizon (Palaeogene Zhepure Formation) at Gulupu section,Duina,Yadong,southern Tibet.The Zhepure Formation was further divided into underlying Limestone Member and overlying Shale Member which conformably contact with each other.Abundant benthic and planktic foraminifera are respectively gained from the Limestone Member and the Shale Member.This paper focuses on the planktic foraminiferal biostratigraphy of the Shale Member.Examination of body and thin-section fossils of the Shale Member has yielded 135 species of 28 planktic foraminiferal genus and 10 planktic foraminiferal biozones (respectvely in ascending order: M.formosa formosa,M.aragonensis,A.pentacamerata,H.nuttalli,G.subconglobata subconglobata,M.lehneri,O.beckmanni,T.rohri,G semiinvoluta,T.cerroazulensis s.l.Zone) were recognized.The planktic foraminfera retrieved from the Shale Member provide it an Eocene age,spanning the interval from the middle Ypresian to Latest Priabonian (P7-P17,deposited ~52-34Ma),indicating that the final closure of the Tethys seaway in this region occurred at ~ 34 Ma.