The Paleogene-Neogene Paleoclimate Evolution in Western Sector of Northern Margin of Qaidam Basin
Jia Yanyan
Xing Xuejun
Sun Guoqiang
Shi Jian
Liu Shijie
Abstract：Paleoclimate is one of the main sedimentary dynamic factors for the formation of sequence stratigraphy of continental basin. The Paleogene-Neogene paleoclimate evolution in western sector of northern margin of Qaidam basin and surrounding areas was com-plex,but now paleoclimate evolution remains controversial.The elements,TOC and C,O stable isotope content of key well cores and rock debris were measured by geochemical methods.Correlation analysis between paleoclimate indicators shows that:Sr/Ba,Rb/Sr, Sr/Ca,TOC and chloride ion content can be the paleoclimate recovery indicators,however,δ13 C andδ18 O can??t indicate the paleocli-mate evolution process in the study area.Analysis of rock debris chloride ion data of key wells shows that the paleoclimate evolution process in the study area is arid-humid-arid.From Lulehe Formation to upper Shangganchaigou Formation,the paleoclimate gradually evolved from arid to humid climate,including 7 cycles,and lake water salinity decreased,the climate was humid and water was brack-ish overall.From Shangganchaigou Formation to Shizigou Formation,the paleoclimate evolved from humid to arid,including 12 cycles, and brackish water changed to medium brackish water.
Keywords：western sector of northern margin of Qaidam basinPaleogene-Neogenegeochemistrypaleoclimateevolution
Publication Date：2015-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：13( 1955-1967 )