摘要
海陆过渡相页岩气是未来非常规天然气勘探的重要接替领域,开展原位含气性评价及其赋存状态影响因素研究对海陆过渡相页岩气甜点优选具有重要的指导意义。以鄂尔多斯盆地东缘大宁—吉县地区山西组为例,考虑吸附气占据的孔体积,建立了原位页岩含气量校正计算模型,在埋深为1 000~4 000 m范围内,未校正的页岩原位含气量被高估了10.02%~18.79%。海陆过渡相页岩含气性主要受TOC、温度、压力和孔隙空间联合控制。高TOC含量有利于页岩赋存吸附气,高孔隙空间有利于页岩赋存游离气。压力对页岩吸附能力具有促进作用,而温度对页岩吸附能力具有抑制作用,但不同埋深条件下主导因素有所差异。浅层区域,压力的促进作用大于温度的抑制作用;深层区域,温度的抑制作用大于压力的促进作用。基于校正后的原位含气量计算模型,计算了DJ3-4井海陆过渡相页岩原位含气量,其含气量高值段分布在山23亚段的中部,与生产测试结果相吻合。研究结果有效地指导了海陆过渡相页岩气甜点优选。
Marine and continental transitional shale gas is an important replacement field for unconventional gas exploration in the future.In-situ gas evaluation and the study of factors affecting the occurrence state have impor⁃tant guiding significance for the selection of sweet spots of marine and continental transitional shale gas.Taking the Shanxi Formation in Daning–Jixian area,the eastern margin of Ordos Basin as an example,a corrected in-situ shale gas content calculation model is established considering the pore volume occupied by adsorbed gas.In the depth range of 1000-4000 m,the in-situ gas content of uncorrected shale is overestimated by 10.02%-18.79%.The gas bearing properties of marine and continental transitional shale are mainly controlled by total or⁃ganic carbon(TOC),temperature,pressure and pore space.High TOC is conducive to adsorbed gas and high pore space is conducive to free gas.Pressure can promote the gas adsorption capacity of shale,while tempera⁃ture can inhibit it,but the dominant effect is different under different burial depth conditions.In shallow area,the promoting effect of pressure is greater than the inhibiting effect of temperature.In the deep region,the inhibi⁃tion effect of temperature on gas adsorption is greater than the promotion effect of pressure.Based on the correct⁃ed in-situ gas content calculation model,the in-situ gas content of DJ3-4 marine-land transition shale is calculat⁃ed,and its high gas content section is distributed in the middle of Shan23 submember,which is consistent with the production test results.The research results can effectively guide the selection of sweet spots of marine and continental transitional shale gas.
作者
罗力元
李勇
何清波
李树新
李翔
时小松
路俊刚
陈世加
肖正录
尹相东
LUO Liyuan;LI Yong;HE Qingbo;LI Shuxin;LI Xiang;SHI Xiaosong;LU Jungang;CHEN Shijia;XIAO Zhenglu;YIN Xiangdong(National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;Sichuan Natural Gas Geology Key Laboratories,Chengdu 610500,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Key Laboratory of Unconventional Natural Gas Evaluation and Development in Complex Tectonic Areas,Ministry of Natural Resources,Guiyang 550000,China;Guizhou Engineering Research Institute of Oil&Gas Exploration and Development,Department of Natural Resources of Guizhou Province,Guiyang 550000,China;PetroChina Coalbed Methane Co.,Ltd.,Beijing 100028,China)
出处
《天然气地球科学》
CAS
CSCD
北大核心
2024年第12期2215-2227,共13页
Natural Gas Geoscience
基金
国家自然科学基金(编号:42302164,42072185)
中国石油—西南石油大学创新联合体科技合作项目(编号:2020CX030000)
中国石油科技创新基金项目(编号:2022DQ02-0105)
自然资源部复杂构造区非常规天然气评价与开发重点实验室开放课题基金项目(编号:NRNG-202401)联合资助。
关键词
海陆过渡相
页岩气
原位含气性
控制因素
鄂尔多斯盆地东缘
Marine-continental transitional facies
Shale gas
In-situ gas bearing
Controlling factor
Eastern margin of Ordos Basin
