岩性油气藏 ›› 2018, Vol. 30 ›› Issue (4): 149–160.doi: 10.12108/yxyqc.20180418

• 石油工程 • 上一篇    

页岩力学特性的层理效应及脆性预测

王跃鹏, 刘向君, 梁利喜   

  1. 油气藏地质及开发工程国家重点实验室·西南石油大学, 成都 610500
  • 收稿日期:2017-09-13 修回日期:2018-01-14 出版日期:2018-07-21 发布日期:2018-07-21
  • 第一作者:王跃鹏(1991-),男,西南石油大学在读博士研究生,研究方向为石油工程、非常规页岩岩石力学等。地址:(610500)四川省成都市新都区西南石油大学。Email:wangyuepeng91@126.com
  • 通信作者: 刘向君(1969-),女,博士,教授,博士生导师,主要从事岩石物理(含数字岩石物理)、深部/复杂地层工程地质力学、岩石力学与复杂地层井壁稳定性等方面的教学与研究工作。Email:13880093092@163.com。
  • 基金资助:
    国家自然科学基金“富有机质硬脆性页岩水化机理基础研究”(编号:41772151)资助

Influences of bedding planes on mechanical properties and prediction method of brittleness index in shale

WANG Yuepeng, LIU Xiangjun, LIANG Lixi   

  1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China
  • Received:2017-09-13 Revised:2018-01-14 Online:2018-07-21 Published:2018-07-21

摘要: 为系统研究层理面对页岩力学性质的影响机理,以四川盆地焦石坝地区龙马溪组页岩为例,首先使用偏光显微镜及扫描电镜等对页岩岩样进行微观分析,可见页岩的层理、层间微裂缝及微孔隙等较发育,黏土矿物呈定向排列,层间胶结作用较弱;再通过岩石单轴压缩物理实验和RFPA (真实破裂过程分析)数值模拟,系统研究不同的层理角度、层理密度及层理面力学性能等对页岩单轴抗压强度、弹性模量、泊松比及脆性等参数的影响;最后,采用统计学方法提出一种基于层理密度、层理角度、单轴抗压强度及层理面力学性能等参数的页岩脆性预测新方法。结果表明:页岩的弹性模量随着层理角度的增加呈现先减小再增加之后再次减小再次增加的趋势。页岩的单轴抗压强度和脆性指数的特征曲线均近似为U型,随着层理角度的增加而先减小后增大,且在层理角度为45°左右时,两者均达到最小值,在层理角度为0°和90°附近时,两者的值均相对较大。随着层理角度的增加,页岩的泊松比整体上呈现先降低再增加而后再降低的趋势,并在30°左右出现最小值,在70°左右出现极大值。页岩的弹性模量、单轴抗压强度和脆性指数等参数总体随层理密度的增大而降低;泊松比随着层理密度的增大在不同的层理角度表现出不同的状态。不同层理角度岩石的破裂类型不同。强度参数、弹性参数、脆性及破裂模式等均表现出很强的各向异性特征。整体而言,针对页岩力学特性的层理效应研究及脆性预测,可为页岩气的合理开发及页岩气井的井壁稳定提供一定的理论参考。

Abstract: In order to study the mechanism of the effects of bedding planes on the mechanical properties of shale, we carried out the following related experimental researches. After observing the shale samples taken from Long-maxi Formation in Jiaoshiba area in Sichuan Basin by polarizing microscope and scanning electron microscopy, we got that the shales are rich in bedding planes, micro-fractures and micro-pores. The clay minerals are arranged in a directional arrangement, and the cementations of the layers are weak. RFPA numerical simulation basic parameters were acquired by the results of uniaxial physical compression experiments at different bedding plane angles. These are the basis on which the influence of bedding plane angles, the densities of bedding panes and the mechanical properties of bedding planes on uniaxial compressive strength, elastic modulus, Poisson's ratio and brittleness can continue to be studied by using digital simulation method. A new prediction method for shale brittleness index was presented by statistical methods when we only know the densities of bedding planes, the angles of bedding planes, uniaxial compressive strength and the mechanical properties of bedding planes. Numerical simulation experiments results indicated that the characteristics of uniaxial compressive strength and brittleness index at different angles of bedding plane roughly showed the U-shaped changing trend. The maximum value occurred at the bedding plane angles of 0° and 90°, whereas the minimum value occurred at the bedding plane angle of 45°. The elastic modulus of shale decreased with the increase of bedding angles, then increased and then decreased, finally increased. With the increase of bedding plane angles, the value of Poisson's ratio firstly decreased, then increased and finally decreased. And Poisson's ratio got the minimum value at bedding plane angle of 30°, whereas the maximum value at bedding plane angle of 70°. Elastic modulus, uniaxial compressive strength, and brittleness index overall decreased with the increase of the density of bedding planes. Poisson's ratio showed different states at the different bedding plane angles with the increase of the density of bedding planes. The types of rock fracture of uniaxial physical compression experiments are different at different bedding plane angles. The strength parameters, elastic parameters, brittleness and fracture modes all showed very strong anisotropy. The study about the influence of bedding planes on the mechanical properties and the prediction of brittleness in shale can provide a necessary technical foundation for the stability of shale gas wells and rational development of shale gas.

中图分类号: 

  • P313.1
[1] 肖钢, 唐颖. 页岩气及其勘探开发. 北京:高等教育出版社, 2012:10-25. XIAO G, TANG Y. Shale gas and its exploration and development. Beijing:Higher Education Press, 2012:10-25.
[2] 张金川, 徐波, 聂海宽, 等.中国页岩气资源勘探潜力.天然气工业, 2008, 28(6):136-140. ZHANG J C, XU B, NIE H K, et al. Exploration potential of shale gas resources in China. Natural Gas Industry, 2008, 28(6):136-140.
[3] JOSH M, ESTEBAN L, PLANE C D, et al. Laboratory characterization of shale properties. Journal of Petroleum Science & Engineering, 2012, 88-89(2):107-124.
[4] DEWHURST D N, HENNING A L. Geomechanical properties related to top seal leakage in the Carnarvon Basin,Northwest Shelf, Australia. Petroleum Geoscience, 2003, 9(3):255-263.
[5] CIZ R, SHAPIRO S A. Stress-dependent anisotropy in transversely isotropic rocks:Comparison between theory and laboratory experiment on shale. Geophysics, 2009, 74(1):7-12.
[6] ONG S H. Borehole stability. Norman:University of Oklahoma, 1994:10-15.
[7] 徐勇, 吕成福, 陈国俊, 等.川东南龙马溪组页岩孔隙分形特征.岩性油气藏, 2015, 27(4):32-39. XU Y, LYU C F, CHEN G J, et al. Fractal characteristics of shale pores of Longmaxi Formation in southeast Sichuan Basin. Lithologic Reservoirs, 2015, 27(4):32-39.
[8] 龚小平, 唐洪明, 赵峰, 等.四川盆地龙马溪组页岩储层孔隙结构的定量表征.岩性油气藏, 2016, 28(3):48-57. GONG X P, TANG H M, ZHAO F, et al. Quantitative characterization of pore structure in shale reservoir of Longmaxi Formation in Sichuan Basin. Lithologic Reservoirs, 2016, 28(3):48-57.
[9] 陈乔, 刘洪, 王森, 等.重庆地区下志留统龙马溪组页岩基础物性实验研究.科学技术与工程, 2013, 13(15):4148-4152. CHEN Q, LIU H, WANG S, et al.Experimental study of the fundamental physical properties on shale in Longmaxi Formation of Lower Silurian, Chongqing. Science Technology and Engineering, 2013, 13(15):4148-4152.
[10] 陈勉, 金衍, 张广清.石油工程岩石力学.北京:科学出版社, 2008:114-115. CHEN M, JINY, ZHANG G Q. Petroleum engineering rock mechanics. Beijing:Science Press, 2008:114-115.
[11] CHENEVERT M E, GATLIN C. Mechanical anisotropies of laminated sedimentary rocks. Society of Petroleum Engineers Journal, 1965, 5(1):67-77.
[12] MCLAMORE R T, GRAY K E. A strength criterion for anisotropic rocks based upon experimental observations. The 96 th Annual AIME Meeting, Society of Petroleum Engineers, Los Angeles, California, 1967.
[13] SINGH M, SAMADHIYA N K, KUMAR A, et al. A nonlinear criterion for triaxial strength of inherently anisotropic rocks. Rock Mechanics & Rock Engineering, 2015, 48(4):1387-1405.
[14] SHI X, YANG X, MENG Y, et al. An anisotropic strength model for layered rocks considering planes of weakness. Rock Mechanics & Rock Engineering, 2016, 49(9):1-10.
[15] 刘运思, 傅鹤林, 伍毅敏, 等.横观各向同性岩石弹性参数及抗压强度的试验研究.中南大学学报(自然科学版), 2013, 44(8):3398-3404. LIU Y S, FU H L, WU Y M, et al. Experimental study of elastic parameters and compressive strength for transversely isotropic rocks. Journal of Central South University(Science and Technology), 2013, 44(8):3398-3404.
[16] 侯振坤, 杨春和, 郭印同, 等.单轴压缩下龙马溪组页岩各向异性特征研究.岩土力学, 2015, 36(9):2541-2550. HOU Z K, YANG C H, GUO Y T, et al. Experimental study on anisotropic properties of Longmaxi Formation shale under uniaxial compression. Rock and Soil Mechanics, 2015, 36(9):2541-2550.
[17] 衡帅, 杨春和, 张保平, 等.页岩各向异性特征的试验研究.岩土力学, 2015, 36(3):609-616. HENG S, YANG C H, ZHANG B P, et al. Shale anisotropic characteristics of the experimental study. Rock and Soil Mechanics, 2015, 36(3):609-616.
[18] 姚光华, 陈乔, 刘洪, 等.渝东南下志留统龙马溪组层理性页岩力学特性试验研究.岩石力学与工程学报, 2015, 34(增刊1):3313-3319. YAO G H, CHEN Q, LIU H, et al. Experiment study on mechanical properties of bedding shale in Lower Silurain Longmaxi shale southeast Chongqing. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(Suppl 1):3313-3319.
[19] 梁正召, 唐春安, 李厚祥, 等.单轴压缩下横观各向同性岩石破裂过程的数值模拟.岩土力学, 2005, 26(1):57-62. LIANG Z Z, TANG C A, LI H X, et al. A numerical study on failure process of transversely isotropic rock subjected to uniaxial compression. Rock and Soil Mechanics, 2005, 26(1):57-62.
[20] 刘江涛, 刘双莲, 李永杰, 等.焦石坝地区奥陶系五峰组-志留系龙马溪组页岩地球化学特征及地质意义. 油气地质与采收率, 2016, 23(3):53-57. LIU J T, LIU S L, LI Y J, et al. Geochemistry characteristics and its geological significance of shale in the Ordovician Wufeng Formation and Silurian Longmaxi Formation, Jiaoshibaarea. Petroleum Geology and Recovery Efficiency, 2016, 23(3):53-57.
[21] 罗健, 戴鸿鸣, 邵隆坎, 等.四川盆地下古生界页岩气资源前景预测.岩性油气藏, 2012, 24(4):70-74. LUO J, DAI H M, SHAO L K, et al. Prospect prediction for shale gas resources of the Lower Paleozoic in Sichuan Basin. Lithologic Reservoirs, 2012, 24(4):70-74.
[22] 李可, 王兴志, 张馨艺, 等.四川盆地东部下志留统龙马溪组页岩储层特征及影响因素.岩性油气藏, 2016, 28(5):52-58. LI K, WANG X Z, ZHANG X Y, et al. Shale reservoir characteristics and influencing factors of the Lower Silurian Longmaxi Formation in the eastern Sichuan Basin. Lithologic Reservoirs, 2016, 28(5):52-58.
[23] 唐春安, 王述红, 傅宇方.岩石破裂过程数值试验.北京:科学出版社, 2005:49-65. TANG C A, WANG S H, FU Y F. Numerical experiments of rock failure process. Beijing:Science Press, 2005:49-65.
[24] 梁正召, 唐春安, 李连崇, 等.细观介质拉压比对岩石破坏过程的影响.岩石力学与工程学报, 2004, 23(1):7-11. LIANG Z Z, TANG C A, LI L C, et al. Influence of ratio of mesoscopic compressive strength to mesoscopic tensile strength on progressive failure of rock. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(1):7-11.
[25] 夏英杰, 李连崇, 唐春安, 等.基于峰后应力跌落速率及能量比的岩体脆性特征评价方法.岩石力学与工程学报, 2016, 35(6):1141-1154. XIA Y J, LI L C, TANG C A, et al. Rock brittleness evaluation based on stress dropping rate after peak stress and energy ratio. Chinese Journal of Rock Mechanics and Engineering, 2016, 35(6):1141-1154.
[26] JAEGER J C. Shear failure of anisotropic rocks. Geological Magazine, 1960, 97(1):65-72.
[27] 李庆辉, 陈勉, 金衍, 等.页岩脆性的室内评价方法及改进.岩石力学与工程学报, 2012, 31(8):1680-1685. LI Q H, CHEN M, JIN Y, et al. Indoor evaluation method for shale brittleness and improvement. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(8):1680-1685.
[28] RICKMAN R, MULLEN M J, PETRE J E, et al. A practical use of shale petrophysics for stimulation design optimization:All shale plays are not clones of the Barnett Shale. SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 2008.
[29] 刘致水, 孙赞东.新型脆性因子及其在泥页岩储集层预测中的应用.石油勘探与开发, 2015, 42(1):117-124. LIU Z S, SUN Z D. New brittleness indexes and their application in shale/clay gas reservoir prediction. Petroleum Exploration and Development, 2015, 42(1):117-124.
[30] 王俊瑞, 梁力文, 邓强, 等.基于多元回归模型重构测井曲线的方法研究及应用.岩性油气藏, 2016, 28(3):113-120. WANG J R, LIANG L W, DENG Q, et al. Research and application of log reconstruction based on multiple regression model. Lithologic Reservoirs, 2016, 28(3):113-120.
[31] 朱俊访, 李博, 聂阳.多元非线性回归与BP神经网络在香菇多糖提取工艺研究中的应用.海峡药学, 2014, 26(2):15-17. ZHU J F, LI B, NIE Y. Application of multi-nonlinear regress analysis and back-propagation neural network in the research of extracting lentinan. Strait Pharmaceutical Journal, 2014, 26(2):15-17.
[32] 田生昌. Excel软件在非线性回归分析中的应用探讨. 宁夏农林科技, 2011, 52(11):29-31. TIAN S C. Excel software used for multi-nonlinear regress analysis and discussion. Ningxia Journal of Agriculture and Forestry Science and Technology, 2011, 52(11):29-31.
[33] 王中华, 山桂云, 林英武. Excel多元线性回归及在化学中的应用.计算机与应用化学, 2005, 22(9):121-124. WANG Z H, SHAN G Y, LIN Y W. Multi-linear regression analysis using Microsoft excel and it's application in chemistry. Computers and Applied Chemistry, 2005, 22(9):121-124.
[34] 周晨, 冯宇东, 肖匡心, 等.基于多元线性回归模型的东北地区需水量分析.数学的实践与认识, 2014, 44(1):118-123. ZHOU C, FENG Y D, XIAO K X, et al. Research on water requirement in northeast area based on multiple linear regression model. Mathematics in Practice and Theory, 2014, 44(1):118-123.
[35] 靳庭良, 张宝青.回归分析中t检验与F检验关系的进一步探讨.统计与决策, 2009(21):7-9. JIN T L, ZHANG B Q. Further discussion on the relationship between t-test and F test in regression analysis. Statistics & Decision, 2009(21):7-9.
[36] 刘明, 王仁曾. 基于t检验的逐步回归的改进. 统计与决策, 2012(6):16-19. LIU M, WANG R Z. Stepwise regression improvement based on t test. Statistics & Decision, 2012(6):16-19.
No related articles found!
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 黄思静,黄培培,王庆东,刘昊年,吴 萌,邹明亮. 胶结作用在深埋藏砂岩孔隙保存中的意义[J]. 岩性油气藏, 2007, 19(3): 7 -13 .
[2] 刘震, 陈艳鹏, 赵阳,, 郝奇, 许晓明, 常迈. 陆相断陷盆地油气藏形成控制因素及分布规律概述[J]. 岩性油气藏, 2007, 19(2): 121 -127 .
[3] 丁超,郭兰,闫继福. 子长油田安定地区延长组长6 油层成藏条件分析[J]. 岩性油气藏, 2009, 21(1): 46 -50 .
[4] 李彦山,张占松,张超谟,陈鹏. 应用压汞资料对长庆地区长6 段储层进行分类研究[J]. 岩性油气藏, 2009, 21(2): 91 -93 .
[5] 罗 鹏,李国蓉,施泽进,周大志,汤鸿伟,张德明. 川东南地区茅口组层序地层及沉积相浅析[J]. 岩性油气藏, 2010, 22(2): 74 -78 .
[6] 左国平,屠小龙,夏九峰. 苏北探区火山岩油气藏类型研究[J]. 岩性油气藏, 2012, 24(2): 37 -41 .
[7] 王飞宇. 提高热采水平井动用程度的方法与应用[J]. 岩性油气藏, 2010, 22(Z1): 100 -103 .
[8] 袁云峰,才业,樊佐春,姜懿洋,秦启荣,蒋庆平. 准噶尔盆地红车断裂带石炭系火山岩储层裂缝特征[J]. 岩性油气藏, 2011, 23(1): 47 -51 .
[9] 袁剑英,付锁堂,曹正林,阎存凤,张水昌,马达德. 柴达木盆地高原复合油气系统多源生烃和复式成藏[J]. 岩性油气藏, 2011, 23(3): 7 -14 .
[10] 石战战,贺振华,文晓涛,唐湘蓉. 一种基于EMD 和GHT 的储层识别方法[J]. 岩性油气藏, 2011, 23(3): 102 -105 .