Paleoecology Characteristics And Paleoclimate Significance Of Cenozoic Pollen In Dongping Area In Qaidam Basin

The research scope of this paper is Dongping area,which is in front of A-erh-chin Mountains.It's a third-level tectonic in Yiliping sunken subregion in the west of Qaidam Basin sunken area,and west to Jianding mountain,south to Jian mountain,east to Niudong and Eboliang NO.1,north to Niubei area in north of Dongping.The samples of this paper are from Swells.It can via specific identification of fossils to build sporopollen assemblages,and to regain the types of paleovegetation,and also analysis the characters of the paleoclimate.The main achievements and cognition as follow:1?processing and identification of fossils.This paper totally process and analysis 437 samples from 8 wells:Jian 3,E2,E3,Jian 1,Jian 2,Feng 2 and Han 2.These samples belong to 135 genus and 247 species.2?division of assemblages and the significance of their time.According to the characters of these fossils and the place they deposit,these fossils can divide into 8 assemblages.Comparing with the same beds of the rest parts of the basin and other places in China,to discuss the time significance of each assemblage.3?Research of paleovegetation and paleoclimate.The main sporopollen fossil is divided in Humidity type(hygrophilous,mesic and xerophytic)and temperature type(hyperthermal,thermophilic,eurythermic)based on the ecological contrast between sporopollen fossil and related modern maternal plants.This paper made research and analyzed about cenozoic sporopollen fossil assemblages,composition and structure for each assemblages,the compound differentiation,simple differentiation degree,degree of dominance and richness and recover the main vegetation type and the affected climate characteristics for each ages based on characters of sporopollen assemblages.4?the buried type and ecological type of sporopollen and study on paleobathymetry change.The hydrophytes can be divided into emerged plants,floating plants and submerged plants from the shallow to deep.It also can be divided into 3 buried types according to the characters of their transfer and burial:local components?part components and area components.According to the changes of burial type and ecological type,it can discuss their relationship with paleobathymetry.With the increase of water deep,the emerged plants and floating plants are decrease,and submerged plants increase,and also discuss the relationship between the distribution of pollen and datum plane.