摘要
海陆过渡相页岩是页岩气勘探的重要接替领域。与海相页岩相比,海陆过渡相页岩层段岩石类型多样、厚度分布不稳定、有机质丰度较低,页岩气的勘探难度较大。随着鄂尔多斯盆地东缘海陆过渡相页岩气勘探的不断突破,亟需加强页岩气成藏过程、保存条件及时空匹配等方面的精细化研究,以明确不同构造区海陆过渡相—页岩气—富集主控因素与成藏模式。研究以鄂尔多斯盆地东缘北部和南部页岩气潜力区为研究对象,在详细对比页岩基本地质条件和生烃潜力基础上,从能量场—演化、保存条件—有效性及成藏模式特征进行系统总结。综合分析认为:鄂东缘北部太原组页岩层段生烃潜力优越,具备页岩气勘探潜力;南部山西组页岩生烃潜力要优于太原组页岩,但能量场及页岩气保存条件的研究还相对薄弱;海陆过渡相页岩气成藏模式建立的关键参数缺乏校正,有待精细研究。未来需要在精细刻画岩性组合和流体单元的基础上,开展能量场的重建和盖层封闭性的评价,精细描述能量场对页岩气赋存方式的控制,进而准确建立页岩生排烃过程与保存条件的时空匹配关系,从而建立鄂东缘海陆过渡相页岩气的精细成藏模式,以期为该区页岩气高效勘探开发提供重要理论支撑。
The transitional shale is a promising field for shale gas exploration.Compared with the marine shale,the shale of transitional facies has various rock types,unstable thickness distribution and lower organic matter abundance,which makes it difficult to explore shale gas.With the continuous breakthrough of shale gas exploration of transitional facies in the eastern margin of Ordos Basin,in order to improve the accuracy and efficiency of exploration,it is necessary to carry out fine-grained studies on accumulation process,preservation conditions and spatio-temporal matching of shale gas,so as to clarify accumulation regularity and main controlling factors of transitional facies shale gas in different tectonic zones.Focused on the shale gas potential areas in the north and south of the eastern margin of Ordos Basin,in this paper,the evolution of energy field,the validity of preservation conditions and the matching of accumulation models would be summarized systematically based on the detailed comparison of material basis and hydrocarbon generation potential of shale.Comprehensive analysis shows that,(1)in the northern area,the shale member of Taiyuan Formation has rich material foundation and superior hydrocarbon generation potential,which has the exploration potential of multiple types of unconventional resources;(2)the hydrocarbon generation potential of shales in the southern Shanxi Formation is better than that of shales in Taiyuan Formation,but the study of energy field and shale gas preservation conditions are still very weak;(3)the key parameters of establishing accumulation model of transitional shale gas are lack of correction and need to be discussed carefully.In order to clarify the enrichment mechanism of transitional shale gas,it is necessary to reconstruct the energy field and evaluate the sealing property of cap rock on the basis of fine characterization of lithologic assemblage and fluid units.Only by describing the control of energy field on shale gas occurrence mode can we accurately establish the spatio-temporal matching relationship between shale hydrocarbon generation and expulsion process and preservation conditions.The establishment of fine accumulation model of transitional shale gas would provide important theoretical support for the efficient exploration and development of shale gas in the eastern margin of Ordos Basin.
作者
刘雯
赵群
邱振
赵培华
李树新
董大忠
刘洪林
侯伟
张琴
肖玉峰
刘丹
王玉满
周尚文
梁峰
林文姬
LIU Wen;ZHAO Qun;QIU Zhen;ZHAO Peihua;LI Shuxin;DONG Dazhong;LIU Honglin;HOU Wei;ZHANG Qin;XIAO Yufeng;LIU Dan;WANG Yuman;ZHOU Shangwen;LIANG Feng;LIN Wenji(PetroChina Ressearch Institute of Petroleum Exploration and Development,Beijing 100083,China;China National Energy Shale Gas Research(Experiment)Center,Langfang 065007,China;PetroChina Coalbed Methane Company,Beijing 100028,China)
出处
《天然气地球科学》
CAS
CSCD
北大核心
2023年第5期868-887,共20页
Natural Gas Geoscience
基金
中国石油天然气集团有限公司“十四五”上游领域前瞻性基础性项目“海陆过渡相页岩气成藏条件及勘探前景评价研究”(编号:2021DJ2001)资助.
关键词
海陆过渡相
页岩气
鄂尔多斯盆地东缘
页岩气成藏条件
Transitional facies
Shale gas
Eastern margin of Ordos Basin
Accumulation conditions of shale gas
作者简介
刘雯(1989-),女,山东东营人,博士,工程师,主要从事沉积盆地温压场、非常规油气成藏机理研究.E-mail:liuwen0906@126.com;通信作者:邱振(1984-),男,安徽亳州人,博士,高级工程师,主要从事非常规油气沉积学研究.E-mail:qiuzhen316@163.com.
