The Crustal Velocity Structure of Western Inner Mongolia

The terrain of Inner Mongolia is long and narrow, and the geological structure is complicated. The South China crustal velocity model and Inner Mongolia''s optimal crustal velocity model 2015 cannot fully meet the earthquake location requirements of Inner Mongolia. Based on the seismological observations produced by Inner Mongolia Seismic Digital Network from 2009 to 2016, the initial model was obtained by using the linear fit of the seismic phases and the converted travel time curve. The Hyposat results of 225 earthquakes that occurred in western Inner Mongolia were scanned using this model, and the velocity model for western Inner Mongolia was determined as follows:V₁=6.06km/s; V_Pb=6.61km/s; V_n=8.12km/s; H₁=30m; and the Moho depth H=44km. Comparison of the test results of the new model and the reference model shows that the residual error of the new model and the mean deviation of the epicenter location have obviously decreased.