RECOGNITION OF POTENTIAL FAULT ZONES IN ORDOS BASIN AND ITS PETROLEUM GEOLOGICAL SIGNIFICANCE

In the early stage of fault development, the basic characteristics of faults, such as the relative displacement of the upper and lower walls, are not obvious. However, along the trend of future development of faults in this period, there are intrinsic characteristics such as small echelon faults, densely developed fracture zones and linear distribution of buried hills in sags.This trend zone of weak deformation in caprock caused by regional stress field or basement fracture is called Potential Fault Zone.Based on geophysical data and previous research results, potential fault zones in EW, NW and NE directions were identified in the Ordos Basin, which can be divided into basin level, depression level, depression level and trap level according to scale.The study shows that the potential fault zones regulates the structural pattern of the basin, divides depressions and uplifts, accelerates the development of source rocks, controls the distribution of sedimentary systems, improves the inheritance and transportation systems, and has an important impact on the generation and accumulation of oil and gas.