Discussion on back-arc rifting tectonics and its geodynamic regime of the Okinawa Trough

Topographic relief,gravity anomalies,magnetic anomalies and geodynamic regime are pertinently discussed for back-arc rifting tectonics of the Okinawa Trough.They are of different characteristics along the continental slope,trough bottom and island slope,respectively,among the northern,middle and southern trough.En echelon grabens or faults on the trough bottom cut obliquely into the continental slope,accompanying with block ridge rifting intensively southwards.In the southern trough,the Diaoyu Island-Chiwei Islet uplift has got rid of features borne by the continental shelf edge uplift to its north,while rotational rifting driven by collision between Luzon and Taiwan has enhanced the crustal extension.Nevertheless,the inner volcanic arc can be traced to Taiwan along the island slope.Different tectonic features can hardly be interpreted only by a general geodynamic background,and there is a large room of research and study for various grabens typical of the trough.Based on different features indicated by grabens,horsts,faults and their delineating tectonic units,together with diverse magmatism,differences and originations of both tectonic attributes and geodynamic factors are mainly explored for these tectonic structures,aiming at further deepening into research of tectonics and geodynamics of the Okinawa Trough.