摘要
通过1∶5万通远乡幅等2幅区调工作对兰州北部永登县地沟村山城湾岭剖面的磁性地层研究，发现剖面底部黄土为兰州地区迄今为止最老的黄土沉积，形成于1．84Ma．BP以前。磁性地层中出现布容正极性期（B）、松山反极性期（M）。松山反极性期内自上而下出现后贾拉米洛、贾拉米洛、奥杜威等亚极性期。对CaCO3含量、黄土剖面所反映出的古气候进行了研究。
During 1∶50000 regional surveys of the Tongyuanxiang Sheet and another sheet， the authors conducted a magnetostratigraphic study of the Shanchengwanling section， Digou Village， Yongdeng County， north of Lanzhou， and found that the loess at the bottom of the section was the so far oldest loess deposits， formed 1．84Ma ago． There appear the Brunhes normal polarity epoch (B) and Matuyama reversed polarity epoch (M) in the magnetostratigraphic polarity units． Inside the Matuyama reversed epoch， there appear in descending order the Jaramillo and Olduvai polarity subepochs． The authors also studied the paleoclimate reflected by the CaCO3 content and loess section．
出处
《中国区域地质》
CSCD
北大核心
2001年第2期141-145,157,共6页
Regional Geology of China
