Boron Isotope Compositions and Environmental Significance of Sediments from the East Taijnar Salt Lake
The isotopic composition of boron(B)can reflect its geological origin and geological evolu-tion,so it has been widely used in many fields.Through the analysis of geochemistry elements,mineral composition and distribution,and water-soluble component B isotopes in the sediments of the East Taijnar Salt Lake,it was found that the B content of the profile sediment ranged from 5.82 μg/g to 677.70 μg/g,with an average content of 296.26 μg/g.The variation range of δ11B value was between-8.52‰～7.93‰,the average value was-2.81‰,and the correlation between B content and δ11B value was relatively weak(R=0.15).The results indicate that the East Taijnar Salt Lake has undergone reverse(chloride type-sulfate type)and forward(sulfate type-chloride type)evolution of lake sedimentation since the late Pleistocene.The specific characteristics of the lake are as follows,1)the Late Pleistocene to the middle Holocene(27～4.6 ka):under dry and cold climate conditions,the lake was undergoing processes of evaporation and con-centration;2)the Middle to Late Holocene(4.6～0.3 ka):under warm and humid climate conditions,the lake was undergoing the process of dilution;3)the Late Holocene to Present(0.3 ka～):the lake water was affected by evaporation,and the corresponding relationship between sedimentation and climate change was relatively weak,overall being in a state of evaporative concentration.This not only reconstructs the ancient environmental evolution process of Dongtai Salt Lake since the Late Pleistocene,but also provides basic data for the current resource development of the Salt Lake.
East Taijnar Salt LakeSedimentsBoron isotopesPaleoenvironment
NETL
NSTL
万方数据
