Abstract:

The Kelasu structural belt of the Kuqa Depression has favorable geologic conditions for hydrocarbon accumulation.Its structural development and evolution are controlled by regional thrust faults.It is characterized by apparent zonation from south to north,segmentation from east to west and vertical layering.Four structural zones from south to north and five segments from west to east were identified according to different regional faults and structural styles.Faults controlled structure development and their differences,while three factors,namely palaeotectonic setting,detachment layer,and intensity of compressive stress,exerted influence upon the characteristics of the faults,forming different pooling and preserving conditions.The belt is an ideal prospective area for gas exploration because of its well-developed reservoirs,relatively thick salt beds,and location far away from multi-stage activating faults.Dabei and Keshen areas are more practical targets for gas exploration.

Key words: zonation and segmentation, flow deformation of salt beds, strike-slip fault, geologic condition for hydrocarbon accumulation, exploration direction, Kelasu structural belt, Kuqa Depression