四川盆地湖相页岩气地质特征与资源潜力  

Geological characteristics and resource potential of lacustrine shale gas in the Sichuan Basin,SW China

作　　者：李延钧[1,2] 冯媛媛[2] 刘欢[2] 张烈辉 赵圣贤[2] 

机构地区：[1]"油气藏地质及开发工程"国家重点实验室 [2]西南石油大学资源与环境学院

出　　处：《石油勘探与开发》2013年第4期423-428,共6页Petroleum Exploration and Development

基　　金：国家自然科学杰出青年基金(51125019)

摘　　要：分析页岩有机质丰度、类型、成熟度等地球化学特征,及页岩沉积环境、地质特征和发育规模,研究四川盆地下侏罗统自流井组湖相页岩气地质特征及资源潜力。四川盆地自流井组湖相页岩主要发育于东岳庙段和大安寨段,页岩样品有机碳含量、干酪根显微组分、生物标志化合物和镜质体反射率等地球化学分析表明,页岩TOC值一般大于1.0%;有机质类型为Ⅱ1—Ⅲ型,湖盆中心主要为Ⅱ1型;Ro值为1.05%～1.82%,具有较强的生气能力。自流井组页岩厚度约为40～150 m,分布面积广,页岩平均孔隙度为1%～5%,渗透率主要为0.001×10 3～0.100×10 3μm2。湖相页岩发育3种地层组合模式:纯页岩、页岩夹灰质条带、页岩夹薄—中层介壳灰岩,页岩中石英含量较高,利于页岩气开采;页岩中发育的灰质条带、介壳灰岩可进一步提高页岩储集层的经济可采性。容积法估算四川盆地自流井组湖相页岩气资源量约为3.8×1012～8.7×1012m3。The geochemical characteristics of shale such as total organic content, type and maturity, shale sedimentary environment, geological characteristics, and scale of development were analyzed to study the geological characteristics and resource potential of lacustrine shale in the Lower Jurassic Ziliujing Formation in the Sichuan Basin. The Lower Jurassic Ziliujing Formation lacustrine shale is mainly developed in the Dongyuemiao and Da＇anzhai members. The geochemical analysis of the organic carbon content, kerogen macerals, biomarker compounds and vitrinite reflectance of the shale samples showed that the total organic content is generally over 1.0%; the main organic type is 111-111, but type Ill is in the central part of the basin; the vitrinite reflectance value （Ro） is 1.05%-1.82%, thus the shale has a strong ability to generate gas. The thickness of the distributed Ziliujing shale is approximately 40-150 m, the average porosity is 1%-5%, and the permeability is 0.001 × 10^-3-0.100× 10^-3 μm2. The lacustrine shale consists of different assemblages： pure shale, shale with imbedded lime band, and shale with thin-middle shell limestone. The shale has high quartz content, favorable for exploitation of shale gas; the lime band and the shelly limestone, which are developed in the shale can further improve the shale economic recoverability. The estimated shale gas resources of the Ziliujing lacustrine shale by volumetric method is about 3.8×10^12- 8.7×10^12 m3.

关 键 词：页岩气 湖相 地质特征 资源潜力 自流井组 四川盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探]