3D topography of the Moho discontinuity in the Taiwan area as extracted from travel time inversion of PmP phases

The reflective signals are often used to find a particular reflective interface. Therefore, we used the travel time of the PmP phase to investigate the Moho depth beneath Taiwan in this study. We used the directionality and rectilinearity functions to increase the accuracy and the convenience of the PmP phase identification. In all, we selected 1054 earthquakes with 13,715 travel time data of the PmP phase to invert the attitude of the Moho discontinuity. From the results, we offer these conclusions: (1) The distribution of the Moho depth in Taiwan trends NNE–SSW, which is consistent with the topography. (2) The deepest part of the Moho discontinuity is beneath the Central Mountain Range, 38 km in depth. And the depth of the Moho discontinuity beneath the Peikang Basement High is only 26 km. (3) The Western Coastal Plain is divided into an active continental margin and a passive continental margin by the Peikang Basement High. (4) The Moho depth beneath the northern part of the Coastal Range is deeper than the southern part because of more vigorous collision activity.

► We used a practical method to identify the PmP phase accurately.
► A simple inversion method is applied to PmP travel time inversion.
► We investigated a detailed Moho depth model in the Taiwan area.
► The Peikang Basement High is a barrier resisting the plate collision.
► The Western Coastal Plain is divided into two types of continental margins.