Geodesy and Geodynamics (Mar 2021)

Regional characteristics of the lithospheric structure in the southeast of North China revealed by explosion seismology

  • Zhenyu Fan,
  • Jinren Zhao,
  • Cejun Ma,
  • Mingxin Qu,
  • Xiaoguo Deng,
  • Baofeng Liu,
  • Yan Hai

Journal volume & issue
Vol. 12, no. 2
pp. 110 – 124


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Based on the blasting seismic detection data obtained in the southeast of North China in recent years, this paper comprehensively analyzes and studies the crust-mantle lithospheric structure and seismological characteristics of different tectonic regions, such as offshore basins, west Shandong uplift, Tanlu fault zone and Jiangsu-Shandong orogenic belt. The low-velocity Pg waves in Dongying depression and Northern Jiangsu basin reveal the unstable basement structure with extremely thick sediments. The travel time of Pg wave is characterized by relatively low propagation velocity and small crustal thickness of offshore continental margin; the first break time and high apparent velocity of Pg wave in west Shandong uplift indicate that the sedimentary basement is relatively thin. The Pm wave shows the characteristic of dominant wave in the first-order velocity discontinuity of the crust-mantle interface, which reflects the high crustal velocity and stable structure in west Shandong uplift. The Pm and Pl wave are obviously complicated, which can reflect the crust-mantle lithospheric structure of the transitional zone between Tanlu fault zone and Jiangsu-Shandong orogenic belt. The small time difference between Pn and PL waves can be regarded as the highly destructive seismological manifestation of Tanlu fault zone on the crust-lithosphere scale. Based on many geophysical phenomena such as electrical structure, density structure and terrestrial heat flow, it is believed that the lithospheric destruction degree of Tanlu fault zone and Jiangsu-Shandong orogenic belt was high during the destruction of the North China Craton.