石油与天然气地质 ›› 2019, Vol. 40 ›› Issue (3): 669-677.doi: 10.11743/ogg20190322

• 开发工程 • 上一篇    下一篇

致密储层体积压裂作用范围及裂缝分布模式——基于压裂后实际取心资料

牛小兵1,2, 冯胜斌1,2, 尤源1,2, 梁晓伟1,2, 辛红刚1,2, 淡卫东1,2, 李廷艳1,2, 任继胜3   

  1. 1. 中国石油 长庆油田分公司 勘探开发研究院, 陕西 西安 710018;
    2. 低渗透油气田勘探开发国家工程实验室, 陕西 西安 710018;
    3. 中国石油集团 渤海钻探工程有限公司 第二录井分公司, 河北 任丘 062550
  • 收稿日期:2019-02-15 修回日期:2019-03-27 出版日期:2019-06-28 发布日期:2019-04-26
  • 作者简介:牛小兵(1977-),男,高级工程师,低渗透-致密油气田勘探和评价。E-mail:nxb_cq@petrochina.com.cn。
  • 基金资助:
    国家科技重大专项(2016ZX05046-005);中国石油天然气股份有限公司重大科技专项(2016E-0501)。

Fracture extension and distribution pattern of volume fracturing in tight reservoir: An analysis based on actual coring data after fracturing

Niu Xiaobing1,2, Feng Shengbin1,2, You Yuan1,2, Liang Xiaowei1,2, Xin Honggang1,2, Dan Weidong1,2, Li Tingyan1,2, Ren Jisheng3   

  1. 1. Exploration and Development Research Institute of Changqing Oilfield Company, PetroChina, Xi'an, Shaanxi, 710018, China;
    2. National Engineering Laboratory for Exploration and Development of Low-Permeability Oil & Gas Fields, Xi'an, Shaanxi 710018, China;
    3. No.2 Mud Logging Branch Company, CNPC Bohai Drilling Engineering Co., Ltd., Renqiu, Hebei, 062550, China
  • Received:2019-02-15 Revised:2019-03-27 Online:2019-06-28 Published:2019-04-26

摘要: 体积压裂在地层中的有效作用范围和压裂缝特征是非常规油气勘探、开发非常关注的问题。本文依据长庆油田在鄂尔多斯盆地致密油试验区完钻的取心井岩心资料、测井资料和分析化验资料,对经大规模体积压裂后储层中产生的人工压裂缝进行了识别和表征,进而分析了致密储层体积压裂改造区人工裂缝发育特征,探讨了体积压裂的有效作用范围、压裂缝的空间分布等关键问题。观察结果表明,X233致密油试验区长7段体积压裂后油层段块状砂岩中发育长度0.13 m近垂直的张性微裂缝,邻近长度1.49 m油层见大量层理缝顺层或斜交延伸,油气外渗显著,为压裂改造后形成的人工缝。综合分析认为,长7段致密油层体积压裂后,由有限数量的主缝、压裂影响形成的大量微裂缝及受压裂影响延伸或扩展的层理缝共同构成了改造后储层的裂缝特征;现阶段技术条件下,体积压裂改造区宏观裂缝网络扩展范围有限,微裂缝分布较广,油层剩余油饱和度依然很高,表明致密油藏体积压裂效果还有进一步优化的空间。

关键词: 微裂缝, 压裂缝, 体积压裂, 储层, 致密油, 延长组长7段, 鄂尔多斯盆地

Abstract: The extension and distribution of hydraulic fractures in stimulated reservoir volume (SRV) after volume fracturing are the key for unconventional oil and gas exploration and development.The artificial fractures created in reservoirs after volume fracturing were identified and characterized based on the actual coring data,logging data and laboratory data of the coring wells completed in the tight oil pilot area of the Ordos Basin.Subsequently,the development characteristics of artificial fractures in the simulated reservoir volume (SRV) were analyzed,and the effective extension and spatial distribution of the hydraulic fractures were discussed.The results show that under volume fracturing,the nearly vertical extensional mirco-fractures of 0.13 m in length were created in the oil-bearing massive sandstones in the Chang 7 of the tight oil pilot zone X233,and many bedding-parallel or -crossing fractures were observed in oil layers about 1.49 m away from the operational area.Hydrocarbon extravasation along these fractures is significant,indicating that they are the artificial fractures generated by fracturing.By comprehensive analysis,we found that a hydraulic fracture network consists of limited number of main fractures,a large number of micro-fractures generated and bedding-parallel fractures extended or expanded by fracturing.Meanwhile,the extension range of macro-fracture network in the SRV is limited,but the micro-fractures are widely developed,and the remaining oil saturation of the reservoir stays high,all of which indicate that there is still room to optimize the volume fracturing technology for tight oil reservoir.

Key words: micro-fracture, hydraulic fracture, volume fracturing, reservoir, tight oil, the 7th member of the Yanchang Formation, Ordos Basin

中图分类号: