2024年新疆乌什MS 7.1地震数据产品及其分析OA

On January 23,2024,an MS 7.1 earthquake occurred in Wushi,Xinjiang Uygur Autonomous Region,where the Indian Plate and the Eurasian Plate collide.After the earthquake,the China Earthquake Networks Center(CENC)started the emergency response immediately,and the National Seismic Network Center rapidly outputted the seismic data products to provide basic data for the study of seismogenic tectonics and the assessment of seismic hazards in the seismic source area.Based on the data from the China Seismic Networks,the double-difference location method is used to relocate the Wushi mainshock and the sequence of 3 487 aftershocks within 38 days and the result shows that the location of the mainshock is(41.28°N,78.62°E),with a depth of 31 km,while the aftershock sequence is distributed from northeast to southwest,with a length of about 80 km,whose focal depth is predominantly distributed in the range of 30 km or shallower,with the fault plane trending to the northwest.Meanwhile,based on the obtained seismic location and previous source mechanism results,the Coulomb stress distribution at different depths of this earthquake is calculated by using the PSGRN/PSCMP code,and the result shows that the occurrence of the mainshock causes the source area a stress unloading status,while the triggering effect of the mainshock on the occurrence of aftershocks is analyzed.Finally,the instrumental intensity of this earthquake is calculated with the data from the China Earthquake Early Warning Network and shows that the maximum intensity value is Ⅸ,concentrated in a small region and mainly focused on the NEE direction.Based on the above results and the surrounding geological structure,the MS 7.1 event in Wushi,Xinjiang is considered to be a thrust-type earthquake with a left-lateral slip component.