油气藏评价与开发 ›› 2018, Vol. 8 ›› Issue (2): 1-6.

• 油气地质 • 上一篇    下一篇

川东北元坝中部地区须家河组致密储层裂缝特征及成因探讨

李虎1,2,3,范存辉1,2,秦启荣1,2,张玮3,吴全鹤3   

  1. 1. 西南石油大学油气藏地质及开发工程国家重点实验室,四川 成都 610500
    2. 西南石油大学地球科学与技术学院,四川 成都 610500
    3. 中国石油塔里木油田分公司,新疆 库尔勒 841000
  • 收稿日期:2017-02-06 出版日期:2018-04-30 发布日期:2018-04-30
  • 作者简介:第一作者简介:李虎(1986—),男,在读博士研究生,构造地质,地质工程研究
  • 基金资助:
    四川省应用基础研究项目“冲断带前缘地腹高陡逆断裂形成机理及裂缝发育量化预测”(2017JY0176)

Fracture characteristics and its genesis of tight reservoir in Xujiahe formation of central Yuanba area in Sichuan basin

Li Hu1,2,3,Fan Cunhui1,2,Qin Qirong1,2,Zhang Wei3,Wu Quanhe3   

  1. 1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China
    2. School of Geoscience and Technology; Southwest Petroleum University, Chengdu 610500, China
    3. Tarim Oilfield Company, PetroChina, Korla 841000, China
  • Received:2017-02-06 Online:2018-04-30 Published:2018-04-30

摘要:

川东北元坝中部地区须家河组致密气藏近年来取得油气勘探的重大突破,裂缝对天然气的运移,富集成藏及产能具有重要影响.综合运用野外露头,岩心,成像测井,包裹体分析以及声发射实验资料,对该区裂缝特征及成因进行研究.研究区主要发育构造成因的低角度剪切缝和高角度剪切缝,具有裂缝延伸中等,宽度小,多闭合,密度较小,充填程度较低的特征,高角度缝和直立缝有效性最好;构造裂缝主要形成期次有三期.第一期为燕山运动晚期,受近SN向构造应力场挤压,形成了NW—SE和NE—SW两组平面“X”型共轭剪切裂缝和近SN向低角度剖面剪切缝,古地应力的最大有效主应力为18.8 MPa;第二期为喜马拉雅早—中期构造运动,在NE的挤压力作用下形成近SN向,近EW向平面“X”型共轭剪切缝,古地应力的最大有效主应力为27.9 MPa;第三期为喜马拉雅运动晚期,构造应力方向仍为NE,主要形成NW向剖面“X”型剪切缝,古地应力的最大有效主应力为38.6 MPa.

关键词: 致密储层, 裂缝特征, 形成期次, 成因模式, 须家河组, 元坝中部

Abstract:

The tight gas reservoir in the central Yuanba area of Sichuan basin is one of the major breakthrough in oil and gas survey in recent years. The fractures have important influence on the migration, enrichment and production capacity of the natural gas. Based on the outcrop, core, imaging log, inclusion analysis and acoustic emission experiment data, we studied the fracture characteristics and its genesis of structural fractures in this area. The low-angle shear and high-angle shear fractures lead to the tectonic origin. The fractures have the characteristic of middle scale, minor width(sealed), high thickness, lower density and less filled degree. The high-angle and vertical fractures have better validity. It shows that there are three fracture generations in central Yuanba area: the first stage fractures are formed in late-Yanshanian tectonic movement, NW—SE and NE—SE of plane "X" conjugate shear fractures and low section shear fractures are formed under the compression of SN tectonic stress. The maximum effective principal stress of the paleostructural stress is 18.8 MPa. The fractures in the second stage are formed in middle Himalaya tectonic movement, SN and EW of plane "X" conjugate shear fractures are formed under the compression of NE tectonic stress. The maximum effective principal stress of the paleostructural stress is 27.9 MPa. The third stage are formed in late Himalaya tectonic movement. The structural stress direction is still NE, which mainly forms NW angle section shear fractures and the maximum effective principal stress of the paleostructural stress is 38.6 MPa.

Key words: tight reservoir, fractures characteristics, formation stage, genetic pattern, Xujiahe Formation, central Yuanba area

中图分类号: 

  • TE121