Activity of Cenozoic fault system in the Luxi Block and deep dynamics

Based on field observation and previous researches, this paper devotes to the Cenozoic fault system in the Luxi Block, with focuses on the connection between the shallow and deep earthquakes and geodynamic mechanism.The results show that the NW and WNW-trending shallow faults are both domino-style faults with sinistral strike slipping according to focal mechanisms.The two sets of faults, together with the NE-trending faults control the formation and development of Cenozoic basins.In depth, there is a gently dipping decollement structure on a large-scale low-velocity anomaly, which is coupled with the shallow system.The deep transitional zones between the high and low anomaly zones controls the distribution of two strong NW-trending earthquake zones.The subduction of the Pacific Plate results in crustal thinning and mantle upwelling which triggered a small-scale convetion within the mantle wedge and resulted in uplifting of the Luxi Block.