新疆阿尔金山南缘长沙沟断陷盆地洪积物时代厘定及古气候环境分析  

Paleoclimate and environment analysis and age dating of proluvium at Changsha ditch fault basin in the south of Altun Mountain Area,Xinjiang

作　　者：杨济远 郭金城 于龙 赵静仪 齐慧云 常雅辉 齐琳 高幸 YANG Jiyuan;GUO Jincheng;YU Long;ZHAO Jingyi;QI Huiyun;CHANG Yahui;QI Lin;GAO Xing(Hebei Regional and Geological Survey Institute/Geotourism Research Center of Hebei Province,Langfang 065000,Hebei,China)

机构地区：[1]河北省区域地质调查院(河北省地学旅游研究中心),河北廊坊065000

出　　处：《矿产与地质》2023年第5期995-1002,共8页Mineral Resources and Geology

基　　金：中国地质调查局基础调查项目“新疆阿尔金地区1∶5万(J45E012015、J45E012016、J45E012017、J45E013015、J45E013016、J45E013017)六幅区域地质调查”(1212011085033)资助。

摘　　要：新疆阿尔金山长沙沟断陷盆地第四系发育。本文对长沙沟断陷盆地洪积物开展了岩石学、光释光(OSL)年代学及孢粉分析研究。洪积物岩石组合多为复成分砂砾石层夹含砾粗砂透镜体,砂砾分选、磨圆中等,多为松散状,局部为半固结状;该时期洪积物中以木本植物花粉占优势,灌木与草本植物花粉居于次要地位,植被类型主要为针阔混交林,松属、栎属、栗属等为主要的组成部分,表明该时期长沙沟一带气候温暖较湿多雨,为中纬度地区高山地理环境;光释光(OSL)年龄测试,年龄分布于87.3~109.5 ka之间,时代厘定为中更新世。Quaternary system is developed in the Changsha ditch fault basin of the Altun Mountains in Xinjiang.In this paper,the study of petrology,optical luminescence(OSL)geochronology and sporopollen analysis of the proluvium in the Changsha ditch fault basin are carried out.The rock assemblage of diluvium is mainly composed of multiple component sand gravel layers with coarse sandstone lenses containing gravels.The gravels are poorly sorted and rounded,mostly loose and partially semi consolidated.In the diluvium of this period,the woody plant pollen is dominant,and the shrub and herb pollen is in a secondary position,the vegetation type is mainly coniferous and broad-leaved mixture forest,and the pine,oak,chestnut and other genera are the main components,it is indicated that the climate around Changsha valley is warm,wet and rainy,and it is a geographical mountain environment in the middle latitude region.The OSL age test result shows that the age ranges from 87.3 ka to 109.5 ka,which is determined as the Middle Pleistocene.

关 键 词：阿尔金 洪积物 中更新世 光释光测年 孢粉分析 

分 类 号：P534.631[天文地球—第四纪地质学]