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本文利用地震面波频散资料进行反演,得到了中国各地区地壳结构的层状模型。中国地壳可以划分为青藏、蒙古、华北、华南和塔里木等五个大陆块体,其频散曲线和地壳层状结构是彼此不同的.一般可以用沉积层、花岗岩层和玄武岩层来代表,后四个区在上地幔和玄武岩层中的波速值比较接近.青藏和华北地区在地壳中的平均波速值较低,地壳结构的纵横向变化显著,康腊面不是稳定而明显的速度间断面,某些部位上存在着低速层,这两个地区的地震活动之所以十分强烈,与上述地壳深部构造有直接关系.其余三个地区的地壳显示了类似稳定地台的某些特征.中国沿海地区的地壳可以大致以长江口为界分成南北两部分,分属于华北和华南地壳.中国地壳厚度在东部为32—40公里,青藏高原60—70公里.沉积层在塔里木盆地最厚,达11公里,其他地区一般为3—8公里.
In this paper, seismic surface wave dispersion data are used for inversion, and the layered model of crustal structure in various regions of China is obtained. The crust in China can be divided into five continental blocks such as Qinghai-Tibet, Mongolia, North China, South China and Tarim, whose dispersion curve and crustal layered structure are different from each other, generally represented by sedimentary, granitic and basalt layers. The wave velocities of the four regions in the upper mantle and basalts are relatively close, and the average velocity of the crust in Qinghai-Tibet region and North China is lower than that in the crust. The longitudinal and transverse changes of the crustal structure are significant. The Kangla face is not a stable and obvious velocity discontinuity, There are low-velocity layers in some parts of the earth where seismic activity is so intense that it is directly related to the above-mentioned deep crustal structure.The crust in the remaining three areas shows some features similar to a stable platform.China’s coastal areas Of the crust can be roughly divided into northern and southern parts of the Yangtze River estuary, belonging to the North China and South China crustal thickness of the crust in the east 32-40 km, 60-70 km of the Qinghai-Tibet Plateau sediments in the highest in the Tarim Basin, up to 11 km , Other areas are generally 3-8 km.