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The distributions of cosmogenic nuclide ~(10)Be in the upper and lower salt units from a core(36.4°N,94.5°E) in the Chaidamu Basin,Qinghai,China have been measured by means of accelerator-mass spec-trometer.The comparison of these ~(10)Be resuhs measured on salt and detritus fractions shows that thegeochemical behaviour of ~(10)Be is detritus-phile,In this area ~(10)Be influx is different in the past tens ofthousands of years,which is suggested to be related to climatic fluctuations during late Pleistocene.It seemsthat ~(10)Be influx is higher in the humid climate environment than in the dry climate environment.The~(230)Th-age estimates of two salt units have been determined.The corrected ages of the lower unit show aclimate shift from humid to dry at about 50 Ka ago in this area.
The distributions of cosmogenic nuclide ~ (10) Be in the upper and lower salt units from a core (36.4 ° N, 94.5 ° E) in the Chaidamu Basin, Qinghai, China have been measured by means of accelerator-mass spec-trometer. The comparison of these ~ (10) Beresuhs measured on salt and detritus fractions shows that the geochemical behavior of ~ (10) Be is detritus-phile, In this area ~ (10) Be influx is different in the past tens of thousands of years, which is suggested to be related to climatic fluctuations during late Pleistocene. At seem (10) Be influx is higher in the humid climate environment than in the dry climate environment. (230) Th-age estimates of two salt units have been determined.The corrected ages of the lower unit show aclimate shift from humid to dry at about 50 Ka ago in this area.