不同边界条件断层端部应力集中效应及对裂缝发育的启示

doi:10.11743/ogg20190121

摘要/Abstract

摘要：

与断层应力集中相关的裂缝发育区是致密油气和页岩油气聚集的有利区。以光弹性物理模拟和有限元数值模拟为技术手段，探讨断层端部应力场的平面展布规律，并结合弹性力学理论分析，解析断层端部应力场的分布机理。结果表明，挤压背景下断层端部的压应力集中区以断层端部圆弧最凸出端点为中心以双曲线形式向外呈“8”字形展开状延伸，其控制范围随边界应力强度增加而增大；在0°~90°范围内随断层走向与边界应力方位夹角增大呈整体增强的趋势，在75°时最大，断层形态及模拟时的建模方式对断层端部应力场有重要影响。断层端部的应力集中区是裂缝储层油气勘探开发的高潜力区。

关键词: 光弹性, 有限元, 应力集中, 裂缝, 断层, 致密储层, 页岩

Abstract:

A fracture development play related to stress concentration of fault zone has high potentials for tight reservoirs and shale oil and gas.This study combined the methods of photo elastic physical modeling and finite element simulation to discuss the planar distribution patterns of stress field at fault's end,and took advantage of the elasticity mechanical theory to analyze the mechanism of stress field distribution.The results indicate that the fault's end displays the concentration of compression stress under the compression background.The stress concentration district extends outward in the shape of numeral "8" following a hyperbolic path centered on the most salient point of the fault's arc end,and its influence range increases with the growth of boundary stress intensity.The stress concentration degree tends to get stronger with the angle between boundary stress direction and fault strike increasing when the angle in the range of 0° to 90°,and reaches its summit at 75°.Besides,both the shape and the modeling method of fault have a significant impact on fault's end stress field.All in all,the stress concentration district at the fault's end has great potentials for the exploration and development of fracture reservoirs.

Key words: photoelastic, finite element, stress concentration, fracture, fault, tight reservoir, shale

中图分类号:

TE121.2

邱登峰,云金表,刘全有,等. 不同边界条件断层端部应力集中效应及对裂缝发育的启示[J]. 石油与天然气地质, 2019, 40(1): 205-214. doi: 10.11743/ogg20190121 Qiu Dengfeng,Yun Jinbiao,Liu Quanyou,et al. The stress concentration effect at fault end under various boundary conditions and its implications for fracture development[J]. Oil & Gas Geology, 2019, 40(1): 205-214. doi: 10.11743/ogg20190121

参考文献

[1] De Joussineau G,Petit J P,Gauthier B D M.Photoelastic and numerical investigation of stress distributions around fault models under biaxial compressive loading conditions[J].Tectonophysics,2003,363(1):19-43.
[2] Perrodon A.Petroleum systems:Models and applications[J].Journal of Petroleum Geology,1992,15(2):319-325.
[3] Treagus S H.A theory of stress and strain variations in viscous layers,and its geological implications[J].Tectonophysics,1981,72(1):75-103.
[4] 苏生瑞.断裂构造对地应力场的影响及其工程意义[J].岩石力学与工程学报,2002,21(2):296-296. Su Shengrui.Effect of fractures on rock stresses and its significance in geological engineering[J].Chinese Journal of Rock Mechanics and Engineering,2002,21(2):296-296.
[5] 苏生瑞,朱合华,王士天,等.断裂物理力学性质对其附近地应力场的影响[J].西北大学学报(自然科学版),2002,32(6):655-658. Su Shengrui,Zhu Hehua,Wang Shitian,et al.The effect of fracture properties on stress field in the vicinity of a fracture[J].Journal of Northwest University(natural science edition),2002,32(6):655-658.
[6] 沈海超,程远方,王京印,等.断层对地应力场影响的有限元研究[J].大庆石油地质与开发,2007,26(2):34-37. Shen Haichao,Cheng Yuanfang,Wang Jingyin,et al.Study of finite element on effects of faults on ground stress field petroleum[J].Geology and Oilfield Development in Daqing,2007,26(2):34-37.
[7] 孙礼健,朱元清,杨光亮,等.断层端部及附近地应力场的数值模拟[J].大地测量与地球动力学,2009,29(2):7-12. Sun Lijian,Zhu Yuanqing,Yang Guangliang,et al.Numerical simulation of ground stress field at ends and vicinity of a fault[J].Journal of Geodesy and Geodynamics,2009,29(2):7-12.
[8] 黄醒春,夏小和.断层周边应力场的原位实测及数值反演[J].上海交通大学学报,1998,32(12):55-59. Huang xingchun,Xia Xiaohe,Shen Heping.Measurement and back analysis on the initial rock stress field around the faults[J].Journal of Shanghai Jiaotong University,1998,32(12):55-59.
[9] 沈海超,程远方,赵益忠,等.基于实测数据及数值模拟断层对地应力的影响[J].岩石力学与工程学报,2008,27(增2):3985-3990. Shen Haichao,Cheng Yuanfang,Zhao Yizhong,et al.Study on influence of faults on geostress by measurement data and numerical simulation[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(supplement 2):3985-3990.
[10] 黄祖智,唐荣昌.四川地区强震发生条件的综合分析[J].地震研究,1997,20(2):185-192. Huang Zuzhi,Tang Rongchang.Comprehensive analyses of strong earthquake occurrence condition in Sichuan area[J].Journal of Seismological Research,1997,20(2):185-192.
[11] 刘中春,吕心瑞,李玉坤,等.断层对地应力场方向的影响机理[J].石油与天然气地质,2016,37(3):387-393. Liu Zhongchun,Lyu Xinrui,Li Yukun,et al.Mechanism of faults acti-ng on in-situ stress field direction[J].Oil & Gas Geology,2016,37(3):387-393.
[12] Gale J F W,Laubach S E,Olson J E,et al.Natural fractures in shale:A review and new observations[J].AAPG Bulletin,2014,98(11):2165-2216.
[13] Lyu W,Zeng L,Zhang B,et al.Influence of natural fractures on gas accumulation in the Upper Triassic tight gas sandstones in the northwestern Sichuan Basin,China[J].Marine & Petroleum Geology,2017,83:60-72.
[14] 邱登峰,周雁,袁玉松,等.鄂西渝东区构造裂缝发育特征及力学机制[J].海相油气地质,2016,21(4):51-59. Qiu Dengfeng,Zhou Yan,Yuan Yusong,et al.Characteristics and mechanism of structural fractures in western Hubei-eastern Chongqing area[J].Marine Origin Petroleum Geology,2016,21(4):51-59.
[15] 周雁,袁玉松,邱登峰.泥页岩构造裂缝形成演化模式——以四川盆地东部泥页岩为例[J].石油与天然气地质,2015,36(5):828-834. Zhou Yan,Yuan Yusong,Qiu Dengfeng.A discussion on formation and evolutionary pattern of shale structural fracture:A case study of shale in western Sichuan Basin[J].Oil & Gas Geology,2015,36(5):828-834.
[16] 李新景,胡素云,程克明.北美裂缝性页岩气勘探开发的启示[J].石油勘探与开发,2007,34(4):392-400. Li Xinjing,Hu Suyun,Cheng Keming.Suggestions from the development of fractured shale gas in north America[J].Petroleum Exploration and Development,2007,34(4):392-400.
[17] Li Z,Li L,Huang B,et al.Numerical investigation on the propagation behavior of hydraulic fractures in shale reservoir based on the DIP technique[J].Journal of Petroleum Science & Engineering,2017,154.
[18] 刘建国,孙其诚,金峰,等.颗粒接触力检测方法评述[J].岩土力学,2009,30(增刊):121-128. Liu Jianguo,Sun Qicheng,Jin Feng,et al.Review of contact force measurement in granular[J].Materials Rock and Soil Mechanics,2009,30(supplement):121-128.
[19] Bombolakis E.Photoelastic study of initial stages of brittle fracture in compression[J].Tectonophysics,1968,6(6):461-473.
[20] Davidson G,Nye J.A photoelastic study of ice pressure in rock cracks[J].Cold Regions Science and Technology,1985,11(2):141-153.
[21] R Soliva,Maerten F,Petit J P,et al.Field evidences for the role of static friction on fracture orientation in extensional relays along strike-slip faults:Comparison with photoelasticity and 3-D numerical modeling[J].Journal of Structural Geology,2010,32(11):1721-1731.
[22] 单家增,张占文,陈绍生,等.大民屯凹陷安福屯潜山带古构造应力场与裂缝发育特征的光弹物理模拟实验研究[J].石油勘探与开发,2004,31(4):15-18. Shan Jiazeng,Zhang Zhangwen,Chen Shaosheng,et al.Photo-elastic experiments of paleo-tectonic stresses field and fracture development characters on Anfutun buried hill,Damintun sag[J].Petroleum Exploration and Development,2004,31(4):15-18.
[23] 马寅生,张兴.黄骅坳陷新生代构造应力场演化的光弹模拟与石油地质条件分析[J].地质力学学报,2002,8(3):219-228. Ma Yinsheng,Zhang Xing.Photoelastic experimental modelling of evolution of cenozoic tectonic stress field and analysis of petroleum geological condition in Huanghua depresson[J].Journal of Geomechanics,2002,8(3):219-228.
[24] 颜丹平,周美夫,田崇鲁,等.裂缝性岩石裂缝扩展的光弹构造物理模拟——以南华北盆地户部寨沙河阶组为例[J].地质学报,2006,79(5):602-607. Yan Danping,Zhou Meifu,Tian Chonglu,et al.A photoelastic experiment for fracture extending in fractured rocks:An example from the Shahejie formation in the southern north China basin[J].Acta Geologica Sinica,2006,79(5):602-607.
[25] 殷秀兰,马寅生,张西娟,等.渤中坳陷中部地区构造应力场光弹模拟实验研究[J].中国地质,2008,34(6):1122-1129. Yin Xiulan,Ma Yinsheng,Zhang Xijuan,et al.Photoelastic modeling of the tectonic stress field in the central part of the Bozhong depression[J].Geology in China,2008,34(6):1122-1129.
[26] 张兴,马寅生.黄骅坳陷构造应力场演化光弹模拟实验[J].石油勘探与开发,1996,23(1):21-24. Zhang Xin,Ma Yinsheng.Photoelastic modeling experiment of tectonic stress field evolution in Huanghua depression[J].Petroleum Exploration and Development,1996,23(1):21-24.
[27] 邱登峰,郑孟林,张瑜,等.塔中地区构造应力场数值模拟研究[J].大地构造与成矿学,2012,36(2):168-175. Qiu Dengfeng,Zheng Menglin,Zhang Yu,et al.Numerical simulatin of the tectonic stress field in the Tazhong area[J].Geotectonica et Metallogenia,2012,36(2):168-175.
[28] 岳中文,王煦,杨仁树,等.一种动光弹模型材料的制作方法及其应用[J].实验力学,2017,32(2):179-188. Yue Zhongwen,Wang Xu,Yang Renshu,et al.A method of dynamic photoelastic experimental model material and its application[J].Journal of Experimental Mechanics,2017,32(2):179-188.
[29] 计欣华,张丽娜,史丽军,等.数字光弹性相移法中全场等倾角和等差线相位[J].光学学报,2008,28(2):273-278. Ji Xinhua,Zhang Lina,Shi Lijun,et al.Whole field phase of isochromatic angle and isoclinic line in digital photoelastic phase-shifting technique[J].Acta Optica Sinica,2008,28(2):273-278.
[30] 计欣华.工程实验力学.第2版[M].北京:机械工业出版社,2010. Ji Xinhua.Engineering experimental mechanica(version2)[M].Beijing:China Machine Press,2010.
[31] 冯振生.改变环氧树脂材料弹性模量的方法[J].水利学报,1984(1):64-69. Feng Zhensheng.The method of changing the elasticity modulus of epoxy resin materials[J].Journal of Hydraulic Engineering,1984(1):64-69.
[32] 施高萍,祝江鸿,李保海,等.矩形巷道孔边应力的弹性分析[J].岩土力学,2014,35(9):2587-2593. Shi Gaoping,Zhu Jianghong,Li Baoha,et al.Elastic analysis of hole-edge stress of rectangular roadway[J].Rock and Soil Mechanics,2014,35(9):2587-2593.
[33] 杨丽红,何蕴增.无限平面矩形开孔的应力场分析[J].哈尔滨工程大学学报,2002,23(2):106-110. Yang Lihong,He Yunzeng.Stress field ananlysis for infinite plate with rectangular opening[J].Journal of Harbin Engineering University,2002,23(2):106-110.
[34] 祝江鸿,杨建辉,施高萍,等.单位圆外域到任意开挖断面隧洞外域共形映射的计算方法[J].岩土力学,2014,35(1):175-183. Zhu Jianghong,Yang Jianhui,Shi Gaoping,et al.Calculating method for conformal mapping from exterior of unit circle to exterior of cavern with arbitrary excavation cross-section[J].Rock and Soil Mechanics,2014,35(1):175-183.
[35] Kattenhorn,S A,Marshall S T.Fault-induced perturbed stress fields and associated tensile and compressive deformation at fault tips in the ice shell of Europa:implications for fault mechanics[J].Journal of Structural Geology,2006,28(12):2204-2221.
[36] Tamagawa T,Pollard D D.Fracture permeability created by perturbed stress fields around active faults in a fractured basement reservoir[J].AAPG Bulletin,2008,92(6):743-764.
[37] Blenkinsop T G.Relationships between faults,extension fractures and veins,and stress[J].Journal of Structural Geology,2008,30(5):622-632.
[38] Teixell A,Durney D W,Arboleya M L.Stress and fuid control on décollement within competent limestone[J].Journal of Structural Geo-logy,2000,22(3):349-371.