页岩气储层的形成条件与储层的地质研究内容

Formation condition of gas-bearing shale reservoir and its geological research target

应用沉积学和层序地层学的理论和方法,综合考虑页岩气系统形成的有利条件,结合国内和国外的实例,总结了有利于泥页岩,特别是可作为页岩气储层的富有机质暗色泥页岩形成的时期和沉积环境,认为富有机质暗色泥页岩主要形成在相对海(湖)平面上升时期的海侵(湖侵)体系域,特别是密集段附近的位置;陆相盆地中的湖湾、半深湖—深湖与海相盆地中的半深海—深海盆地、台地边缘深缓坡和半闭塞—闭塞的欠补偿海湾地区是富有机质暗色泥页岩发育的有利地区。通过对美国Bar-nett等页岩气系统的分析,认为制作暗色泥岩等厚图、TOC等值线图、Ro等值线图、暗色泥岩埋深图等单因素基础地质图件,对其进行叠加综合分析,对页岩气的勘探具有很好的指导意义。

According to sedimentology theory and sequence stratigraphy, favorable environment and time for dark organic shale was analyzed and we consider favorable condition for gas system and take domestic and foreign examples in the progress. It can be concluded that dark organic shale, commonly developed in transgressive system tract, especially in condensed section. Arm of lake, semi- deep and deep lacustrine in continental sedimentary basin, and semi-deep and deep sea basin, platform margin deep slope and blocking gulf in marine sedimentary basin are appropriate places for dark organic shale developing. Depending on the analyses of Barnett shale gas system in American, we could say that contour map of TOC, Ro and isobaths of dark mudstone, and so on, are important basic geological maps, and using these maps for shale gas exploration will be an excellent method.