|
|||||
|
|
| Unroofing around Qaidam Basin of northern Tibet at 30 Ma: constraints from ~(40)Ar/~(39)Ar and FT thermochronology on granitoids | |
| 作者姓名： | 王非 罗清华 李齐 万京林 郑德文 王二七 |
| 作者单位： | Institute of Geology Seismological Bureau Beijing 100029 China，Department of Geology Taiwan University Taipei 106 China，Institute of Geology Seismological Bureau Beijing 100029 China，Institute of Geology Seismological Bureau Beijing 100029 China，Institute of Geology Seismological Bureau Beijing 100029 China，Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China |
| 摘 要： | An ~(40)Ar/~(39)Ar and fission track thermochronological study has been carried out on threesuites of granitoids collected along the northern and southern edges of the Qaidam Basin to betterconstrain the mechanisms accommodating the India-Asia collision around the Qaidam Basin(northern Tibet), in order to understand the evolution of the entire deformation area. Mica andK-feldspar have been analyzed and the cooling histories of the latter have been modeled. Thecooling histories based upon K-feldspar modeling and fission track ages show that samples simul-taneously recorded an important cooling event (7.5-10.7℃/Ma) around 30 Ma, which is thoughtto reflect an increase of denudation rate related to the tectonic activity in this area associated withuplift suggesting significant crustal thickening starting around 30 Ma in this area. The estimatedsedimentation rate in the Qaidam Basin, the propagation rate along the Altyn Tagh fault and fieldobservations support this deduction. |
Unroofing around Qaidam Basin of northern Tibet at 30 Ma:constraints from 40Ar/39Ar and FT thermochronology on granitoids |
|
| WANG Fei,Ching-hua Lo,LI Qi,WAN Jinglin,ZHENG Dewen WANG Erqi.Unroofing around Qaidam Basin of northern Tibet at 30 Ma: constraints from ~(40)Ar/~(39)Ar and FT thermochronology on granitoids[J].Science in China(Chemistry),2002,45(Z1). | |
| Authors: | WANG Fei Ching-hua Lo LI Qi WAN Jinglin ZHENG Dewen WANG Erqi |
| Institution: | 1. Institute of Geology, Seismological Bureau, Beijing 100029, China 2. Department of Geology, Taiwan University, Taipei 106, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China |
| Abstract: | An 40Ar/39Ar and fission track thermochronological study has been carried out on three suites of granitoids collected along the northern and southern edges of the Qaidam Basin to better constrain the mechanisms accommodating the India-Asia collision around the Qaidam Basin (northern Tibet), in order to understand the evolution of the entire deformation area. Mica and K-feldspar have been analyzed and the cooling histories of the latter have been modeled. The cooling histories based upon K-feldspar modeling and fission track ages show that samples simultaneously recorded an important cooling event (7.5-10.7℃/Ma) around 30 Ma, which is thought to reflect an increase of denudation rate related to the tectonic activity in this area associated with uplift suggesting significant crustal thickening starting around 30 Ma in this area. The estimated sedimentation rate in the Qaidam Basin, the propagation rate along the Altyn Tagh fault and field observations support this deduction. |
| Keywords: | unroofing ~(40)Ar/~(39)Ar fission track Qaidam Basin multi-domain diffusion |
| 本文献已被 CNKI 万方数据 等数据库收录！ | |