甘肃临夏盆地8～6MaBP的构造变化  

Tectonic change during 8～6 MaBP in Linxia Basin, Gansu Province

作　　者：徐先海[1,2] 方小敏[1,3] 付开道[1] 

机构地区：[1]兰州大学西部环境教育部重点实验室 [2]中国科学院南京地理湖泊研究所,江苏南京210008 [3]中国科学院青藏高原研究所,北京100085

出　　处：《兰州大学学报（自然科学版）》2006年第6期1-5,共5页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金重点基础资助项目(40334038)

摘　　要：甘肃临夏盆地毛沟剖面上半部高精密度古地磁测年结果表明该剖面磁极性年龄为4．34-13．07 MaBP,其中东乡组、柳树组与何王家组的年龄分别为13．07-7．8 Ma,7．8-6．4 Ma和6．40-4．34 MaBP．该测年结果与文献[1]测得的结果基本一致．临夏盆地6．40-6．16 MaBP湖泊沉积环境突变,8 MaBP左右毛沟剖面地层磁偏角发生明显偏转,盆地中王家山剖面银川沟背斜大约在6 MaBP左右发生倾斜与变形,这表明临夏盆地8-6 MaBP经历了一次强烈的构造运动．Maogou Section is located in Linxia Basin, Gansu Province. The fine paleomagnetic measurement of age suggests that the polarity time of Maogou upper section is 4.34-13.07 MaBP. The result is basically consistent with the result of reference [1]. The obvious changes of the sedimental type and the average declinations of Maogou Section by formations both indicate that Linxia Basin experienced a strongly tectonic movement during 8-6 MaBP; the tilting and folding of the strata in the Yingchuanggou anticline, where the Wangjiashan Section is located, further supports the above idea.

关 键 词：临夏盆地毛沟剖面 磁性地层 极性年龄 构造变形 

分 类 号：P931[天文地球—自然地理学] K90[历史地理—人文地理学]