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On the basis of deep seismic profiling carried out in the past six years, the velocity, gcoelectrical and geothermal structures of the crust and upper mantle and tectonic frames of the Moho discontinuity and asthenosphere have been determined for the northern part of North China. A close relationship exists between Cenozoic teetonism and the geodynamic processes in the crust and upper mantle. We surmise that the intense inhomogeneous activities of the asthenospherc between the late Cretaceous and the Cenozoic may have given rise to the following processes: lithospheric breakup, basalt eruptions, increase in geothermal gradient, lower crustal creep, upper crustal spreading, subsidence and the accumulation of sedimentary deposits as well as the development of shallow-level normal faults. The dip angles of such faults gradually decrease with depth and thus disappear in the low velocity layer of the crust.
On the basis of deep seismic profiling carried out in the past six years, the velocity, gcoelectrical and geothermal structures of the crust and upper mantle and tectonic frames of the Moho discontinuity and asthenosphere have been determined for the northern part of North China. A close relationship exists between Cenozoic teetonism and the geodynamic processes in the crust and upper mantle. We surmise that the intense inhomogeneous activities of the asthenospherc between the late Cretaceous and the Cenozoic may have given rise to the following processes: lithospheric breakup, basalt eruptions, increase in geothermal gradient, lower crustal creep, upper crustal spreading, subsidence and the accumulation of sedimentary deposits as well as the development of shallow-level normal faults. The dip angles of such a collision gradually decrease with depth and thus disappear in the low velocity layer of the crust.