鄂尔多斯盆地延长探区天然气勘探开发技术进展与前景展望OA

The southern Ordos Basin is an important area for natural gas reserves and production increase in China.In recent years,the challenges posed by deteriorating resource quality and increasingly complex exploration targets in this area have been successfully addressed through theoretical and technological innovations.As a result,the Yan'an Gas Field has become the fourth largest gas field in China.Based on the practical exploration and development achievements obtained during the 14th Five-Year Plan period,this paper systematically reviews the progress in the exploration and development of tight sandstone gas,carbonate gas,and new types of natural gas resources,and mainly summarizes the achievements in innovative geological understanding,key engineering technological iteration,and geology-engineering integration collaborative research.Then,the development directions of natural gas exploration and development during the 15th Five-Year Plan period and even in the long term are analyzed with consideration of regional resource endowment and low-carbon development trends.The following results are obtained.First,the hydrocarbon accumulation model featuring saturated charging within source rocks,fault-controlled migration outside source rocks,multistage migration-accumulation adjustment and multilayer sweet spot aggregation is established for the complex and superimposed tight sandstone gas reservoirs.This model effectively expands the exploration plays of principal gas reservoirs.Second,exploration breakthroughs are achieved in the new fields of unconventional natural gas including deep coalbed methane(CBM),shale gas,bauxite-hosted gas and helium,and a pattern for synchronous exploration of various resources is constructed.Third,a series of supporting technologies centered on stereoscopic development with mixed well patterns,precision fracture-controlled stimulation of tight sandstone reservoirs,and high-efficiency acid fracturing of complex tight carbonate reservoirs are formed.These technologies collectively improve the development performance of tight complex gas reservoirs significantly.In conclusion,the achievements of geology-engineering collaborative innovation provide powerful support for the natural gas reserves and production increase in the Yanchang exploration area of the southern Ordos Basin,and point out the directions for high-quality development,including mature area potential tapping,new area expansion,and intelligent and green development.