渭河陇西段河流对构造-气候变化的响应  

Response of Weihe River to climatic change in Longxi zone

作　　者：刘小丰[1,2] 李明永[1] 刘洪春[1] 高红山[2] 潘保田[2] 李保雄[1] 范兵[1] 

机构地区：[1]中国地震局兰州地震研究所,兰州730000 [2]兰州大学西部环境教育部重点实验室,兰州73000

出　　处：《干旱区资源与环境》2010年第11期68-72,共5页Journal of Arid Land Resources and Environment

基　　金：国家科技支撑项目"汶川地震断裂带科学钻探"项目;国家自然科学基金(批准号:40401007;40471016);国家重点基础研究发展计划(批准号:2005CB42001)资助

摘　　要：中更新世以来,渭河陇西段共发育了七级阶地,形成年代分别为860ka、787ka、621ka、412ka、128ka、60ka、11ka。研究表明:渭河阶地是在构造和气候共同作用下形成,构造抬升为河流的下切提供一个垂直空间,准0.1Ma周期的气候变化控制着渭河阶地的发育。陇西地区黄土记录表明自860ka以来该地区共经历了10个较大的气候转型事件,此地区并没有发育10级阶地,黄土样品的色度数据显示渭河陇西段缺失的3级阶地可能与气候温暖湿润程度较低及气候的不稳定性波动有关。The seven terraces preverved along Weihe River in Longxi basin since middle Pleistence were estimated to form about 860ka、787ka、621ka、412ka、128ka、60ka、11ka.Analysis on sedimentation characteristics and dating of these terraces showed that seven terraces may be jointly generated by tectonic uplifts and climatic changes.Tectonic uplift provided incision space for the river,and the terraces were controlled by cycles of a period of about 0.1 Ma.The loess information indicated that ten climatic transition events were found in Longxi basin since 860Ka,and the three Absent terraces was considered to be the response to the instability and moist degree of the climate.

关 键 词：陇西 阶地 气候变化 

分 类 号：P467[天文地球—大气科学及气象学]