Acta Petrolei Sinica ›› 2017, Vol. 38 ›› Issue (12): 1371-1380.DOI: 10.7623/syxb201712004

• Petroleum Exploration • Previous Articles     Next Articles

Development characteristics of bentonite in marine shale and its effect on shale reservoir quality: a case study of Wufeng Formation to Member 1 of Longmaxi Formation, Fuling area

Shu Yi1, Lu Yongchao1, Liu Zhanhong2, Wang Chao3, Mao Huawu1   

  1. 1. Faculty of Earth Resource, China University of Geosciences, Hubei Wuhan 430074, China;
    2. College of Marine Science and Technology, China University of Geosciences, Hubei Wuhan, 430074;
    3. Research Institute of Petroleum Exploration and Development, Sinopec Jianghan Oilfield Company, Hubei Wuhan 430223, China
  • Received:2017-04-17 Revised:2017-09-25 Online:2017-12-25 Published:2018-01-05

海相页岩中斑脱岩发育特征及对页岩储层品质的影响——以涪陵地区五峰组—龙马溪组一段为例

舒逸1, 陆永潮1, 刘占红2, 王超3, 毛华武1   

  1. 1. 中国地质大学资源学院 湖北武汉 430074;
    2. 中国地质大学海洋学院 湖北武汉 430074;
    3. 中国石油化工股份有限公司江汉油田分公司勘探开发研究院 湖北武汉 430223
  • 通讯作者: 舒逸,男,1992年9月生,2016年获武汉工程科技学院学士学位,现为中国地质大学(武汉)资源学院矿产普查与勘探专业硕士研究生,主要从事沉积储层方面的研究。Email:cug_sy904@sina.com
  • 作者简介:舒逸,男,1992年9月生,2016年获武汉工程科技学院学士学位,现为中国地质大学(武汉)资源学院矿产普查与勘探专业硕士研究生,主要从事沉积储层方面的研究。Email:cug_sy904@sina.com
  • 基金资助:

    国家重大科技专项(2016ZX05060-004)及国家自然科学基金项目(No.41690131、No.41772148、No.41702149)资助。

Abstract:

Based on fine core description, whole rock/clay X-ray diffraction analysis, argon ion polishing scanning electron microscopy and other test technologies, the development characteristics of bentonite in the marine shale of Upper Ordovician Wufeng Formation-Lower Silurian Member 1 of Longmaxi Formation, Fuling area are studied as well as its relationship with shale reservoir quality from three aspects, i.e., the development characteristics of bentonite, shale reservoir quality and the development mechanism of reservoir quality difference. The results show that there are totally 42 sets of bentonite layers developed in the regional Wufeng Formation-Member 1 of Longmaxi Formation. According to the single-layer and inter-layer thickness of bentonite, such bentonite layers are classified into three stages, i.e., densely developed stage, relatively developed stage and less developed stage. Through comparing the characteristics of shale reservoir quality in different development stages, it is found that the shale reservoir in the relatively development stage has high brittle mineral, high organic carbon content and high gas content, proven as the most favorable shale reservoir development stage. Furthermore, it is explained from two aspects of paleo-ocean redox conditions and paleo-productivity that discrete volcanic eruptions might be the main reason for the changes in the redox conditions during the deposition. Meanwhile, moderate volcanic activity is beneficial to the enrichment of organic matter and siliceous minerals, which also favors the formation of high-quality shale.

Key words: marine shale, bentonite, reservoir quality, Wufeng Formation-Longmaxi Formation, Fuling area

摘要:

以岩心精细描述为基础,借助全岩/黏土X射线衍射分析、氩离子抛光扫描电镜等测试技术,从斑脱岩发育特征、页岩储层品质和储层品质差异性发育机理3个方面,对涪陵地区上奥陶统五峰组—下志留统龙马溪组一段海相页岩中斑脱岩的发育特征及其与页岩储层品质之间的关系进行了研究。研究表明,本地区上奥陶统五峰组—下志留统龙马溪组一段共发育42层斑脱岩层,结合斑脱岩层单层厚度和层间厚度,将其划分为密集发育段、较发育段和欠发育段3个阶段。通过对比不同发育段页岩储层品质特征发现,较发育段具有高脆性矿物、高有机碳含量和高含气性的特征,为最有利页岩储层发育段。此外,从古海洋氧化还原环境和古生产力2个方面阐述了间发性火山活动是导致沉积期氧化还原环境变化的主要原因,且适度的火山活动有利于有机质和生物成因硅质矿物的富集,促进了优质页岩的形成。

关键词: 海相页岩, 斑脱岩, 储层品质, 五峰组&mdash, 龙马溪组, 涪陵地区

CLC Number: