Analysis of Future Strong Earthquake Activity at the Boundary Faults of the Bayan Har Block Based on GPS Data
Nearly ten strong earthquakes(M≥7.0)have occurred on the boundary faults of the Bayan Har block since 1995,providing an opportunity and showing the necessity for the researchers to study the strong earthquake activi-ties along these boundary faults in future.Which boundary fault will be potential place for the next strong earthquake(M≥7.0),and when the earthquake will happen are questions to be addressed.In this article,based on the his-torical earthquake events(M≥7.0)on the boundary faults of the Bayan Har block since 1900,we use the model of the multi-spring slider system to calculate the possible time of the potential earthquake and judge the possible boundary fault on which the earthquake may occur.Then we use the GPS data of the horizontal velocity field in the region of the Bayan Har block from 1991 to 2016 and the homogeneous elastic block model to calculate the long-term seismic characteristics of the boundary faults of the Bayan Har block.We further calculate the seismic proper-ties of the boundary faults in 5 periods(1999-2007,2009-2013,2013-2015,2015-2017,and 2017-2020),and obtain the temporal-spatial evolution characteristics of these faults.On this basis,we analyze the seis-mic trend of the faults with the help of the focal mechanisms of the strong earthquakes(M≥7.0)on the faults since 1995.We find that the seismic characteristics of the boundary faults are consistent with the focal mechanisms,and strong earthquakes(M≥7.0)on the faults since 1995 are caused by the enhancement of the eastward-south-east movement of the Bayan Har block.Strong earthquakes(M≥7.0)are more likely to occur on the Ganzi-Yushu fault and the South Longmenshan fault in ten years.In addition,the east segment of the East Kunlun fault should be paid more attention to.
the Bayan Har blockstrong-earthquake sequenceblock activityhomogeneous elastic modelstrong-earthquake activity
万方数据
维普
