摘要
库车坳陷的第三系盐膏质区域盖层具有厚度大、分布广、岩性致密、突破压力高、地层压力也很高的特点 ,属于封闭性特别强的区域盖层 ;在坳陷的成藏系统中 ,起着应变分隔带、流体压力屏障、油气成藏机制分界线的作用 ;在其上下出现了两种成藏模式———克拉苏模式和大宛齐模式。这套盖层是坳陷油气富集的最重要条件之一 ,也是我国最优良气田———克拉 2大气田形成的最重要条件之一。在其下还会有更多的克拉
The Tertiary halite gypsum sediments constitute the regionally high quality caprocks, deposited from semiclosed bay and lagoon enviconments.These caprocks are characterized by very large thickness(1000m), broad distribution and high compactness, very high pore pressure and a high breakthrough pressure(>60MPa). They play the role of the strain separation zone, pore pressure barrier and the dividing of two pool forming models, i.e. the Kelasu model and the Dawanqi model in the Kuqa Depression. The Kelasu model takes effect below these regional caprocks, with the overpressure in anticline traps,and the Dawanqi model takes effect above thes regional caprocks, with the normal pressure in many kinds of traps.The caprocks are one of the most important conditions of the oil and gas enrichment in this depression and also one of the most importment forming factors of the Kela 2 gigantic gas field. Somemore gas fields similar to Kela 2 can be discovered under the Tertiary caprocks.
出处
《古地理学报》
CAS
CSCD
2000年第4期51-57,共7页
Journal of Palaeogeography：Chinese Edition
关键词
库车坳陷
第三系
油气成藏
成藏模式
盐膏质盖层
Kuqa Depression, Tertiary, halite gypsum regional caprocks, pool forming controlling process, pool forming model
