塔里木盆地克拉苏盐下深层大气田的发现

克拉苏构造带位于库车坳陷北部,其盐下深层大气田为超深高压裂缝性低孔高产砂岩气田,目前已发现油气藏22个,是塔里木盆地天然气的主力产区。1998年发现克拉2气田后,虽坚持勘探,却未再获得重大发现。2006年以来,加强对克拉苏构造带深层的研究,2008年8月,位于克深区带克深2构造的克深2井在白垩系巴什基奇克组获得日产40×104m3高产工业气流,取得了重大勘探突破。此后,经过近10年的研究,在前陆盆地勘探技术、油气地质理论和生产实践3个方面实现了技术突破,指导了克拉苏盐下深层大气田的发现,并围绕复杂山地圈闭落实、储集层形成机理、成藏等地质问题及快速钻进、储集层改造等制约勘探效率的工程技术进行研究,有效支撑了克拉苏盐下深层大气田的高效勘探开发。

Discovery of Kelasu Subsalt Deep Large Gas Field,Tarim Basin

Kelasu tectonic belt is located in the northern Kuqa depression and the discovered subsalt large?deep gas field in the tectonic belt belongs to ultra?deep high?pressure gas fields with low?porosity high?yield fractured sandstones.Up to now 22 oil and gas reservoirs have been discovered in the gas field,which are the major production areas for natural gas in Tarim basin.There was no significant break?through after the discovery of Kela 2 gas field in 1998.Since 2006,the research of the deep zones in Kelasu tectonic belt has been strength?ened,and in Aug.,2008 commercial gas flows were gained from the Cretaceous Bashijiqike formation in the Well Keshen?2 which is locat?ed in the Keshen?2 structure of Keshen area and the daily gas production was 40×104 m3,marking a great breakthrough has been gained.Then over 10 years of study,technological breakthroughs have been made on foreland basin exploration technology,petroleum geological theory and production practice,which provides guidance for the discovery of the Kelasu subsalt deep large gas field.The researches on trap identification in complex mountain areas,reservoir forming mechanism and hydrocarbon accumulation,speedy drilling and reservoir refor?mation effectively support the efficient exploration and development of the Kelasu subsalt deep large gas field.