RELATION BETWEEN BASEMENT FRACTURES AND FORMATION OF ENERGY RESOURCES IN ORDOS BASIN
PAN Aifang 1,2, HE Ying1, LI Rongjian3 and XI Xianwu4 (1. Northwest University, Xi’an, SX 710069, China; 2. Xi’an University of Architecture and Technology, Xi’an, SX 710055, China; 3. Changqing Oil Exploration Bureau, Xi’an, SX 710021, China; 4. College of Geological Engineering and Geometry, Chang’an University,Xi’an, SX 710054, China)
The basement fractures and their activities, element geochemistry fields, and the relationship between the element geochemistry fields and the energy resources in Ordos Basin were compared and analyzed in this paper. The results indicate that the basement fractures controlled the distribution features of multi-energy resources, most natural gas and large- to medium-scale coalfields in North Ordos Basin, and most oil fields and medium- to small-scale coalfields in South Ordos Basin. Distribution of fault zones mostly occur in the mixed regions with both natural gas and oil fields. On the other hand, the enrichment of uranium deposits in the study area is controlled by the basement or deep fractures, where element geochemistry fields are closely correlated with basement fractures. The distribution features, strikes and tortuosities of all kinds of element geochemistry fields are related with the basement fractures in the corresponding section, the geochemistry fields and its element combinations are controlled by the basement fractures. Active indication of deep fluids is reflected by the existence and the activities of the basement fractures, and the features of basement fractures and the activities of the basement fractures offer pathways for migration of deep fluids and joint formation of multi-energy resources.