Using seismic data and 3D numerical simulation to study strike-slip faulting and stress field evolution in Honghe Oilfield, Ordos Basin

This work focuses on the strike-slip faulting activity and stress field evolution in Honghe Oilfield, Ordos Basin. With the finite difference software, a series of 3D numerical models were constructed to investigate the two stages of structural superposition. Constrained by the refined seismic structure interpretation and the tectonic evolution of Qinling Mountain in the south and Liupanshan Mountain in the west, the model results indicate that the NW trending Yudu Fault developed first and was controlled by the sinistral strike-slip of basement fault. The Yudu Fault is supposed to be active in the late Jurassic-early Cretaceous, which is mainly attributed to the northwestward compression among different blocks in the northern margin of the Qinling Mountains. The maximum principal stress near the Yudu Fault Zone was oriented NEE during faulting. Subsequently, the NEE trending faults developed and were subjected to distributed sinistral strike-slip faulting during eastward compression of the Liupanshan thrust belt. These faults developed in the late Early Cretaceous or the Cenozoic. The maximum principal stress was oriented in the range of N36°~69° with an average of N53°. This study provides a new constraint on the fault prediction in this area, and also sheds new light on faulting dynamics in the other oilfields in the Ordos Basin.