Chemical weathering history of the southern Tajikistan loess and paleoclimate implications

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:woaini009
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Major chemical elements and Rb, Sr, Ba abundances were measured for loess samples from Chashmanigar loess-soil sequence in southern Tajikistan. And the degree of element loss and intensity of weathering of the samples were calculated. From these calculations we found that the paleosol horizons of the Chashmanigar section were chemically weathered to some extent and the weathering intensity of the soils is stronger than that of loess horizons, indicating that paleosols in southern Tajikistan were deposited in relatively warm and humid interglacial ages. In addition, the southern Tajikistan loess deposited before 0.9Ma BP was more intensely weathered than that deposited after 0.9Ma BP, which may imply the intensification of aridity in this area since 0.9Ma BP. Major chemical elements and Rb, Sr, Ba abundances were measured for loess samples from Chashmanigar loess-soil sequence in southern Tajikistan. And the degree of element loss and intensity of weathering of the samples were calculated. From these calculations we found that the paleosol horizons of the Chashmanigar section were chemically weathered to some extent and the weathering intensity of the soils is stronger than that of loess horizons, indicating that paleosols in southern Tajikistan were deposited in relatively warm and humid interglacial ages. In addition, the southern Tajikistan loess deposited before 0.9 Ma BP was more intensely weathered than that deposited after 0.9 Ma BP, which may imply the intensification of aridity in this area since 0.9 Ma BP.
其他文献
Major element compositions of garnet, clinopyroxene, orthopyroxene andspinel in the garnet-bearing lower crust and upper mantle xenoliths from Hannuoba, North C
The Lower Cambrian black shales of the Niutitang Formation and their lateral equivalents occur widely on the Yangtze Platform, South China. In this study, we ex
Spectral absorption coefficients of the total particulate, ap(λ), nonalgal particulate, ad(λ), and phytoplankton pigment, aph(λ), in the Pearl River estuary
In this paper, we applied the newest emission scenarios of the sulfur and greenhouse gases, i.e. Intergovernmental Panel on Climate Change (IPCC) Special Report
Using the CCM3 global climate model of National Center for AtmosphericResearch(NCAR), this paper comparatively analyzes the characteristics of East Asian monsoo
Black shales, cherts, and associated lithologies in the Early Cambrian of the Yangtze Platform yielded abundant phytoplankton, the earliest well preserved skele
Systematic grain-size analysis has found that Chinese loess generally shows bimodal distribution composed of overlapped coarse and fine components. Sedimentary
Fine particles play an important role in the atmosphere. Research on heterogeneous reactions on the surface of fine particles is one of the frontier areas of at
The Yangtze Block in South China is one of the important regions where Neoproterozoic glacial rocks are well developed and studied. However, the classification