A study on crustal and upper mantle structures in east part of North China Craton using receiver functions

The P-wave and S-wave receiver function analysis has been performed along a profile which consists of 34 broadband seismographs to image the crustal and upper mantle structure in east part of North China Craton(NCC). The results reveal that the Moho interface lies at a depth of more than 30 km below the North China basin and shallows to less than 30 km in the West Shandong (Luxi) uplift which displays a dome-like shape. This Moho depth jump is roughly coincident with the transverse location of the Liaokao fault. An obvious uplift of the Moho is also detected below the Tanlu fault zone, which reflects that the fault may cut through the Moho under it. The lithosphere-asthenosphere boundary (LAB) is observed similar to 100 km beneath the Taihang orogenic belt and increases to similar to 60 km below the Luxi uplift. Farther eastward, it seems to be shallower beneath the Qingdao region. We also apply the slant-stack method to determine Poisson's ratio. The result shows rather uniform distribution of Poisson's ratio in the Luxi uplift. In contrast, it is much variable in the Qingdao region which is the north part of the Sulu-Dabie ultra-high-pressure metamorphic belt, implying a more complex evolution history.