Abstract:

In order to study the crustal structures in the southeastern margin of the Ordos Block, a portable broadband
seismograph array with 22 stations was deployed in the study area. Instead of the linear stacking, a non-linear stacking techniquenamed the phase-weighted stack (PWS) was used to stack the radial receiver functions for each station. The results show that thedepth of Moho in the study area gradually decreases towards the southeast. The Moho discontinuity in different parts of the study area exhibits different features: the depth of Moho in the Ordos block is between 42 and 38 km; the Moho in Weihe-Shanxi graben bulges up by about 3 km; In the Xionger-Funiu Mountains, the depth of Moho is betweem 35 and 33 km; the Moho in the Hehuai basin appears to be complex. To conclude, the PWS Method is useful to enhance the S/N (signal/noise) ratio and determine the depth of Moho beneath the stations in the study area.

Key words: receiver function, phase-weighted stack, H -&kappa, stack, common conversion point stack, crustal structure