Geochemical Characteristics and Sedimentary Environment of the Epipleistocene Peat on Zhaojiayuanzi Sediment Column in Caohai Basin, Guizhou Province
Based on the analytical results of major elements,trace elements and 14C age of the Zhaojiayuanzi sediment column in the Caohai Basin,Weining country,Guizhou Province,China,writers discussed the depositional rate of peat,climatic evolution and provenance from Late Pleistocene to Holocene and the source environment of sediment.The results show that trace elements Li,Sc,V,Cr,Ni,Ga,Rb,Sr,Sn,Cs,Ba,Zr,Th,U et al.are consistent throughout the whole column.14C dating suggests that the age of the basal peat layer in the sediment column is spanned between 33.74 and 23.29 ka BP,and the deposition rates of different layers respectively are 148.4 mm/ka for the bottom peat layer,24.3 mm/ka for the black paleosol,22.4 mm/ka for top layer,so that the deposition rates gradually reduce from the bottom to top.The climate indicators,such as some element ratios (Sr/Ba,Sr/Cu,Rb/Sr,MgO/CaO),and the multi-elements ratios [(CaO + K2O + Na2O)/ A12O3,(Fe2O3 + Al2O3)/(MgO + CaO)] suggest that,during the period from 42.37 ± 1.27 ka BP to 15.60 ± 0.10 ka BP,the ancient climate at ZhaojiaYuanzi area evolved from warm--slight humid →warm--wet →warm--dry →cool--some moist →→cool--moist.The source of sediments has experienced an intense chemical weathering,in which the bottom peat layer,however,was less weathered.
国家科技期刊平台
NSTL
万方数据
维普
