Late Cenozoic deformation subsequence in northeastern margin of Tibet --Detrital AFT records from Linxia Basin  

作　　者：ZHENG Dewen (郑德文) ZHANG Peizhen (张培震) WAN Jinglin (万景林) LI Chuanyou (李传友) CAO Jixiu (曹继秀) 

机构地区：[1]Institute of Geology, China Seismological Bureau, Beijing 100029, China Institute of Geology, China Seismological Bureau, Beijing 100029, China Institute of Geology, China Seismological Bureau, Beijing 100029, China Institute of Geology, China Seismological Bureau, Beijing 100029, China Department of Geology, Lanzhou University, Lanzhou 730000, China

出　　处：《Science China Earth Sciences》2003年第z2期266-275,共10页中国科学（地球科学英文版）

基　　金：This work was supported by the National Key Basic Research Project (Grant No. G1998040701) and the National Natural Science Foundation of China (Grant No. 49825104).

摘　　要：Two events of Tibet uplifting are revealed by detrital apatite fission track (AFT) age data from Linxia Basin. They occurred at about 14 and 5.4-8.0 MaBP respectively. We interpret the first one to be related to the uplifting of the northern Tibet, which might have resulted from convectively removing the thickened lower lithosphere. The second one is a result of Laji Mountain uplifting. Numerous studies of the Tibetan Plateau suggest that the onset time of the deformation in the northeastern margin of Tibetan Plateau and the time of Tibet attaining to its present elevation is about 8 MaBP. They are approximately coincident with the uplift of Lajishan Mountain. It suggests that the northeastern margin of Tibet propagated northeastwardly to its present site in about 8 MaBP for accommodating the sustained convergence between India-Eurasia plate and for keeping its high elevation. The active block pattern dominating the strong earthquake distribution of Chinese continent probably formed at about 8.0-5.4 MaBP.

关 键 词：LINXIA Basin  DETRITAL APATITE fission track  tectonic event  active block. 

分 类 号：P315[天文地球—地震学]