The contemporaneous faults are well-developed in the Qihuan Area of the Western Slope in the western depression of the Liaohe River Rifted Basin. Therefore, one should study the development characteristics and the control of these faults in order to make clear how these faults can influence the structures and reservoirs. These contemporaneous normal faults, characterized by the north-east strike listric faults tilting and sliding in the direction of sag, control the regional structure patterns. Furthermore, from the 3D seismic data, the contemporaneous fault growth index is computed. The relations between the fault growth index and the trap types are analyzed. Finally the general conclusion for this area is that the more intense the fault tectonic activity is, the more advantageous for the formation of local structures. The rollover anticline and the fault nose always develop in a down-dropped block of contemporaneous faults, and these areas are in favour of the hydrocarbon accumulation because of the fine sand distribution in these structures. The conventional well pattern of the oil development is not effective near the contemporaneous faults as their down-dropped block may be overlooked. The research of the contemporaneous faults shows that the areas near these fault down-dropped block have also the potential prospects of the existence of residual oil.

Qihuan Area  /  contemporaneous faults  /  rollover anticline  /  sand distribution  /  residual oil