Tectonic thermal evolution and oil‐gas reservoir in Bachu Upheaval of Tarim Basin, northwest China

Abstract

Regional deep tectonic thermo evolution in sedimentary basin constrains the distributions of shallow layered structure development. There exist several old secular upheaval structures within Tarim Basin, and the studies associated with the relationship between the deep tectonic thermo evolution and oil‐gas formation and reservoir in this region have been considered as an important issue for the future oil‐gas exploration. Located in the Southwest Tarim Basin in Northwest China, Buchu Upheaval region has been considered as one of the most prospective regions for the future oil‐gas exploration. In this upheaval structure, the deep tectonic activities during different geological periods control the size and distribution of the layered structure formation, the level of erosion, the shape of fault fracturing, and the development of unconformity. As we know, therefore, the investigation in the deep tectonic thermo evolution related to the oil‐gas formation and reservoir has become a key issue for the future prospecting for oil‐gas resources in this region. In current study, by integrating geological and geophysical information, such as seismic, gravity, geomagnetic, geothermal, borehole, and outcropping data, in this region, we focus our research work on the investigation of the general relation between the geodynamic background related with the deep tectonic thermal evolution and the oil‐gas formation and reservoir in Bachu Upheaval based on the analysis of the sedimentary thickness, layer sequence, and layer characteristic etc. The main work follow: 1.Using gravity, geomagnetic, and continental heat flow data, we analyze the regional tectonic characteristic and its shape in past; 2. Combing with the thermal‐dynamic conditions, we discuss the tectonic regime related to the different tectonic deformation periods; 3. Based on the interpretation of the seismic and borehole data, we evaluate the oil‐gas formation, migration, and condition of reservoir in the shallow part of the up‐lifted sedimentary layer.