关键词: 库车前陆冲断带, 白垩系, 深层, 盐岩, 勘探发现, 勘探启示

Abstract: After the discovery of Kela-2 gas field, exploration for oil and gas hit bottom in Kuqa Foreland Thrust Belt. Except for Kela-2 gas reservoir, no new boreable traps were discovered. To explore deep oil and gas fields was also faced with such difficulties as geologic complexity, difficult trapping, and lag in technology. To solve the difficulties above, first is to rediscover Kuqa Foreland Thrust Belt, be confident in exploration, and identify main exploration areas; second is to develop seismic and geologic integration technology such as wide line combination, 3D acquisition and processing, modeling of the structure relevant to salt, and phase velocity field building, to discover Keshen-Dabei zone, and to discover and fulfill some drillable traps; third is to intensify development of drilling technology and fulfill efficient and rapid drilling in subsalt ultra-deep, high-pressure and high-temperature gas reservoir. In the past ten years, the exploration depth of Kelasu structural belt was increased from 4000m to 8000m, several large gas fields including Keshen 2 and Bozi 1 gas fields were discovered, and one trillion cubic meters of natural gas resources were gradually identified in Keshen zone. Breakthroughs in exploration of large and deep subsalt gas fields here benefits from innovation of geologic recognition, improvement of exploration techniques, and perseverant exploration practice.