Crustal structure and comparison of different tectonic blocks in North China
华北不同构造块体地壳结构及其对比研究

North China paleocontinental block underwent reconstruction through multi-stage tectonic movements, and the crustal structure in sub-blocks has distinct characteristics. Based on data and results of nearly 30 deep seismic sounding profiles with a total length of about 20000 km, the fine structures of the crust within each sub-block are further studied in North China, structural differences among the blocks are compared. On the basis of different tectonic features, the crust in North China may be divided into 3 classes: a simple crustal structure in Ordos basin in the western part of the region, with an integrated basement structure, showing the crustal structure feature of stable paleocontinent; a relatively simple crustal structure in Taihangshan mountain uplifts located in the middle part of North China, and Yinshan mountain and Yanshan mountain uplifts located in the northern part of North China, where the slight velocity reversal in local areas of middle and lower crusts is possibly related to medium decoupling deformation within the crust caused by the regional crustal thickening and uplifting; a complex crustal structure in the rift-depression basin in the eastern part of North China, with a sinking and fragmentized basement, loosen medium within the crust, low velocity, uplifted Moho and thinned crust, lateral tectonic differences obvious, showing tectonic features of the rebirth crust. Furthermore, crustal sub-block tectonics and related dynamic evolution in North China are comprehensively studied.