楚雄盆地油气保存单元划分与评价

DIVISION AND EVALUATION OF HYDROCARBON PRESERVATION UNITS IN THE CHUXIONG BASIN

楚雄盆地经历了多期构造运动,油气藏形成的关键时段是燕山期,晚燕山期后上覆K2—E地层成为新的区域盖层,喜山运动的挤压作用加强或改造了原先形成的圈闭,同时造成油气重新运聚,形成新的油气保存单元。在油气保存条件综合分析的基础上,结合构造特征、含油气系统研究,将楚雄盆地现今油气保存单元划分为:持续型、残留型、改造型及重建型4种基本类型。最后,对各油气保存单元进行了综合评价,进而提出了下一步有利勘探目标。

The Chuxiong Basin has experienced multiphase tectonic movements,of which Yanshan movement was critical to the formation of oil and gas reservoirs.The overlying K2-E became new regional seals after late Yanshan period,the compression of Himalayan movement enhanced or reformed the pre-existing traps and caused remigration and re-accumulation of hydrocarbons,resulting in new hydrocarbon preservation units.Based on a comprehensive analysis of hydrocarbon preservation conditions and in combination with study of tectonic features and petroleum systems,current hydrocarbon preservation units in the Chuxiong Basin are divided into four basic types,including sustained,relic,reformed,and reconstructed preservation units.The hydrocarbon preservation units are comprehensively evaluated and favorable targets of future exploration are presented.