浑善达克沙地全新世中晚期地层化学元素特征及其气候变化

在系统考察浑善达克沙地的基础上,选择沙地北部锡林浩特全新世地层剖面样品进行全量化学元素分析和¹⁴C年代测定;并根据地球化学特征的变化,推论8kaBP以来的气候变化过程。结果表明,8kaBP以来区域气候具有干旱化的趋势,并经历了6个冷干暖湿变化旋回,气候变化可划分为4个阶段:8060~7100aBP,气候寒冷干旱;7100~5500aBP,气候温暖半湿润;5500~3500aBP,气候发生频繁的干湿波动;3500aBP特别是2200aBP以来气候以干旱为主。

Characters of Chemical Elements in Strata of Middle and Late Holocene in Hunshandake Desert and the Indicating Climatic Changes

On Hunshandake Desert,located in the eastern part of Inner Mongolia,are mainly distributed by fixed and semi-fixed sand dunes,which interlaced with mobile dunes,lakes and rivers.The deposits in Holocene strata of the study region belong to aeolian and lacustrine facies.The five typical geologic sections are selected and sampled for analyzing the total chemical elements and dating the forming age.The distributing characters and the integrated parameters of chemical elements corporately indicated that the regional climate had aridization tendency and has experienced 6 cycles between cold-arid and warm-humid since 8 ka BP.On the whole,the climatic changes could be divided into 4 stages:8 060~7 100 a BP,cold and arid;7 100~5 500 a BP,warm and semi-humid;5 50~3 500 a BP,frequently fluctuated between arid and humid;3 500 a BP to present,especially from 2 200 a BP,arid climate predominated.