Small Grants for Exploratory Research: Collaborative Project: Rapid Response to the November 14, 2001 Kunlun Fault Earthquake

来自阿拉斯加大学、加州大学洛杉矶分校和中国地震局的科学家沈正康和中国正在对2001年11月14日发生在西藏的7.9级昆仑断裂地震进行快速响应。这次地震为测量8级地震的震后形变提供了一个难得的机会。这场地震发生在已知相对速度约为1 mm/年的现有大地网内。中国地震局在震后一周内在破裂附近建立了三个连续记录的GPS站点，在大约150公里之外建立了第四个GPS站点。此外，2001年12月还对青藏公路沿线17个现有和新建的GPS站点进行了调查。第二个野外活动是从青藏公路向西延伸GPS网络，在近场地表破裂两侧的断层上增加新的站点。这项调查重复了11-12月调查的所有地点的测量结果，提供了初步的震后结果。这些测量将有助于更好地了解西藏北部异常厚重的地壳的流变结构，以及如此大的地震引发的震后过程。

EAR-0209434/EAR-0209892Shen Zheng-Kang/FreymuellerScientist from the University of Alaska, University of California Los Angeles, and the China Seismological Bureau are carrying out a a rapid response to the November 14, 2001 Mw~7.9 Kunlun fault earthquake in Tibet. This earthquake provides a unique opportunity to measure the postseismic deformation of an M~8 earthquake that occurred within a pre-existing geodetic network in which relative site velocities are known to about 1 mm/yr., Three continuously recording GPS sites near the rupture and a fourth about 150 km away were established one week after the event by the China Seismological Bureau. Also, 17 existing and new GPS sites along the Qinghai-Tibet highway were surveyed in December, 2001. A second field campaign is extending GPS network westward from the Qinghai-Tibet highway, adding new sites along the fault on either side of surface rupture in the near field. This survey is repeating measurements at all of the sites surveyed in November-December, providing the initial postseismic results. These measurements will lead to a better understanding of the rheological structure of the exceptionally thick northern Tibetan crust as well as the postseismic processes triggered by such a large event.