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

美国阿拉斯加大学、加州大学洛杉矶分校和中国地震局的科学家们正在对2001年11月14日发生在西藏的昆仑山口西7.9级地震进行快速反应。这次地震提供了一个独特的机会来测量一个8级地震的震后形变，该地震发生在一个预先存在的大地测量网内，其中相对场地速度已知为1 mm/yr。中国地震局在事件发生一周后建立了三个位于破裂附近的连续记录GPS站点和第四个位于约150公里处的GPS站点。2001年12月，对青藏公路沿线沿着17个现有和新建GPS站点进行了测量。第二次野外活动是从青藏公路向西延伸GPS网络，在近场沿地表破裂两侧的断层沿着增加新的站点。这次调查是在11月至12月调查的所有地点重复测量，提供初步的震后结果。这些测量结果将有助于更好地了解异常厚的北方西藏地壳的流变结构，以及由这样一个大事件触发的震后过程。

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.