滇黔北地区五峰组—龙马溪组页岩气富集条件及有利区预测

发布时间：2018-12-10 14:52

【摘要】：滇黔北地区上奥陶统五峰组—下志留统龙马溪组海相页岩具有较好的页岩气资源前景,但目前对于其复杂地质条件下的页岩气成藏富集规律仍不明确。为此,基于最新的钻井资料,结合野外露头剖面观察和样品测试结果,对该区五峰组—龙马溪组的沉积环境,优质页岩的分布与埋深、有机地球化学指标、储集性参数、含气性等页岩气富集条件进行了系统分析,预测了优质页岩有利区带并评价其勘探潜力。结果表明:(1)该区五峰组—龙马溪组为浅水陆棚—深水陆棚沉积,沉积环境控制了优质页岩的厚度与分布,地史沉积格局和后期构造运动改造控制了底界埋深——底界埋深介于0~4 000 m,优质页岩沉积厚度介于0~60 m;(2)该区优质页岩有机碳含量高(1.0%~4.0%),热演化程度高(过成熟),有机质类型稳定(腐泥型—偏腐泥混合型),生烃强度高(1.0×10~8~4.0×10~8m~3/km~2),生烃潜力较大;(3)优质页岩脆性矿物含量较高,破裂潜力较好,储层储集空间类型多、微裂缝发育;(4)区内局部保存条件较好,具备页岩气成藏的良好地质条件。结论认为:盐津西、筠连南、威信—叙永—古蔺、习水东等4个区域五峰组—龙马溪组页岩气成藏条件优越,具备良好的页岩气勘探潜力,为该区最有利的页岩气勘探区带。
[Abstract]:The marine shale of upper Ordovician Wufeng formation and Lower Silurian Longmaxi formation in northern Yunnan and Guizhou has a good prospect of shale gas resource, but the law of shale gas accumulation under complex geological conditions is still unclear. Based on the latest drilling data, combined with field outcrop profile observation and sample test results, the sedimentary environment of Wufeng formation and Longmaxi formation, distribution and burial depth of high quality shale, organic geochemical index and reservoir parameters are studied. The enrichment conditions of shale gas, such as gas bearing, were systematically analyzed, the favorable zones of high quality shale were predicted and its exploration potential was evaluated. The results are as follows: (1) the Wufeng formation and Longmaxi formation are shallow-water and deep-water shelf deposits, and the sedimentary environment controls the thickness and distribution of high-quality shale. The geological history sedimentary pattern and the late tectonic transformation controlled the buried depth of the bottom boundary between 0 ~ 4 000 m, and the thickness of the high quality shale deposit was between 0 ~ 60 m. (2) the high quality shale in this area has high organic carbon content (1.0%), high thermal evolution (over mature), stable organic matter type (mixed type of saprophyte and partial saprophytic mud) and high hydrocarbon generation intensity (1.0 脳 10 ~ (8) ~ (8) ~ (4) 脳 10~8m~3/km~2). The potential of hydrocarbon generation is great; (3) the brittle minerals of high quality shale have higher content, better fracture potential, more reservoir space types and microfracture development, (4) good local preservation conditions and good geological conditions for shale gas reservoir formation. The conclusion is that the four regions of Yanjin Xi, Junlian Nan, Weixin, Xuyong and Gulin, Xishuidong, Wufeng formation and Longmaxi formation have excellent reservoir forming conditions and good shale gas exploration potential, which is the most favorable shale gas exploration zone in this area.
【作者单位】：中国地质调查局成都地质调查中心;国土资源部沉积盆地与油气资源重点实验室;重庆地质矿产研究院;国土资源部页岩气资源勘查重点实验室;
【基金】：国家科技重大专项“页岩气勘查评价技术试验与应用推广”(编号:2016ZX05034-004) 中国地质调查局油气基础性公益性地质调查二级项目“四川盆地下古生界海相页岩气基础地质调查”(编号:DD20160176)
【分类号】：P618.13

【相似文献】