HR: 1340h
AN: G13B-1240    [Abstracts]
TI: ERROR ANALYSIS OF STRAIN RATES FROM GPS MEASUREMENTS
AU: * Zhu, S
EM: zhushoubiao@gmail.com
AF: Institute of Crustal Dynamics,China Earthquake Administration, No.1,Anningzhuanglu,Haidian, Beijing, 100085, China
AU: Shi, Y
EM: shiyl@gucas.ac.cn
AF: Graduate University of Chinese Academy of Science, Yuquanlu, Shijingshan, Beijing, 1000049, China
AB: At first, we calculate the strain rates from GPS vectors with the approach combining kriging method with the derivative of shape functions. Then we propose a method to carry out error analysis of the strain rates, estimated from GPS vectors with measurement errors, on the base of Monte Carlo technique. The result shows that the orientations of principal strain rates are consistent with those of the P axis and T axis of focal mechanisms. The absolute value of the component of strain rate in the west of China is approximately 5 times larger than that of eastern China on the whole. Taken the Chinese continent as an example, independent computation of strain rates is repeated for a large number of times, and the errors as well as the components of strain rates, are computed through statistical theory. The error result shows that the errors of principal strain rates are larger in Himalayas and in the east side of the Tibetan plateau than those in other places. However, the relative errors in the East China are much larger than those in the west China such as in and around the region of the Tibet. In general, the strain rates in the west China are accurate and stable. The strain rate and its error results reveal that the orientations of principal strain rates are consistent with those of tectonic stresses in and around the Tibet. And especially the tensile strain rates from GPS vector data in the interior and in the southeast of the Tibet are in good agreement with the seismic and geological observations.
DE: 8110 Continental tectonics: general (0905)
SC: Geodesy [G]
MN: 2007 Fall Meeting