基于改进的BET多层吸附模型的深层页岩吸附气含量测井评价方法  

Log Evaluation Method for Adsorbed Gas Amount in Deep Shale Based on Modified BET Multilayer Adsorption Model

作　　者：钟光海 李跃纲 李生杰[3] ZHONG Guanghai;LI Yuegang;LI Shengjie(Research Institute of Shale Gas,PetroChina Southwest Oil and Gas Field Company,Chengdu,Sichuan 610041,China;Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province,Chengdu,Sichuan 610041,China;Unconventional Petroleum Research Institute,China University of Petroleum(Beijing),Beijing 102249,China;Chongqing Shale Gas Exploration and Development CO.LTD.,Chongqing 401120,China)

机构地区：[1]中国石油西南油气田公司页岩气研究院,四川成都610041 [2]页岩气评价与开采四川重点实验室,四川成都610041 [3]中国石油大学(北京)非常规油气科学技术研究院,北京102249 [4]重庆页岩气勘探开发有限责任公司,重庆401120

出　　处：《测井技术》2024年第1期84-93,共10页Well Logging Technology

基　　金：国家科技重大专项“深层页岩气地质综合评价技术现场试验”(2019F-31-01);中国石油天然气股份有限公司科学研究与技术开发项目“深层页岩气测井岩石物理与解释评价方法研究”(KT_(2)020-10-10)。

摘　　要：含气量是页岩储层评价的一项关键指标,页岩含气量受温度-压力耦合影响,特别在地层压力较高情况下,准确预测页岩储层吸附气含量较为困难。针对深层页岩气储层高温高压环境下甲烷吸附特性,提出了改进的BET多层吸附模型,建立了一套深层页岩储层吸附气含量测井评价方法。应用该方法对川南深层页岩储层进行含气量评价,结果表明:利用改进的BET多层吸附模型计算的吸附气含量更符合实际地质情况,结合相应层段游离气含量,计算所得的页岩总含气量精度较高,且与现场保压取心获取的总含气量较为一致。基于改进的BET多层吸附模型的吸附气含量评价方法在川南深层页岩气区块具有较好的适应性,可为深层页岩地质甜点评价和资源潜力分析提供技术支撑。Gas content is a key index of shale reservoir evaluation.The gas content is influenced by the coupling of temperature and pressure.Especially under high formation pressure,it’s difficult to accurately predict the adsorbed gas amount of shale reservoirs.Regarding the methane adsorption characteristics in deep shale gas reservoirs under high-temperature and high-pressure condition,a modified BET multi-layer adsorption model is derived.A set of log evaluation methods for adsorbed gas amount of deep shale reservoirs has been established.By applying this method to evaluate the gas content of deep shale reservoirs in southern Sichuan basin,the results show that the adsorbed gas amount calculated by modified BET multi-layer adsorption model is more in line with the actual geological conditions.Combined with the free gas volume corresponding the depth,the total gas content of shale is calculated by this method,and the result is accurate and consistent with that obtained by on-site pressure maintaining coring.The evaluation method of adsorbed gas amount based on the modified BET multi-layer adsorption model has good adaptability in deep shale gas blocks in southern Sichuan basin,and provides strong technical support for geological dessert evaluation and resource potential analysis of deep shale.

关 键 词：四川盆地 吸附气含量 等温吸附实验 BET吸附 含气量 

分 类 号：P631.84[天文地球—地质矿产勘探]