山西分区地壳速度模型的建立及应用

将山西地区划分为北部、中部和南部3个区域,利用2009～2019年山西省及周边50 km范围内的地震事件波形资料,使用线性拟合、折合走时及Hyposat批量定位等方法确定各分区的地壳速度模型.采用批量定位比较残差、PTD方法测定震源深度及非天然地震事件检验等方法对分区模型进行验证,结果显示,相对山西2015速度模型,分...

Establishment and Application of Regional Crustal Velocity Model in Shanxi Zone

In this study, the Shanxi area is divided into three areas of north, middle and south, using seismic event waveform data in and around 50 km in Shanxi province from 2009 to 2019, using linear fitting, reduced travel time, and Hyposat batch processing methods. The crustal velocity models of each subarea are determined, and three methods are used to verify the subarea model: batch positioning to compare residuals, PTD method to determine the source depth, and unnatural seismic events. The results show that the zoning model has better applicability to the Shanxi 2015 velocity model. The difference between the zoning model and the Shanxi 2015 velocity model is mainly reflected in the propagation velocity of the P-wave in the upper crust and Moho and the depth of the Moho. The zoning model shows that the propagation velocity of the crust gradually decreases from north to south, while the velocity of the Moho surface gradually increases, and the depth of the Moho shows a trend of thick north and thin south. The upper crust velocity value is higher due to the Datong volcano in the northern region, while the lower crust and Moho velocity are lower, and the crust thickness is thicker. The upper crustal velocity of southern region is lower, due to the existence of huge thick sediments.