郑永香,刘建军
ZHENG Yongxiang,LIU Jianjun

• 1:西南石油大学地球科学与技术学院
• 2:中国科学院武汉岩土力学研究所

摘要(Abstract)：

为了研究单裂缝注水后裂缝周围的地应力场重分布情况,并分析地应力重分布的影响因素,基于断裂力学理论,分析了单裂缝周围的地应力场分布,建立了地应力转向和地应力差值的计算方法,并分析了裂缝长度,缝内压力和原始地应力场条件对地应力场的重分布的影响。结果表明:单裂缝注水后引起的地应力重分布主要体现在地应力方向和地应力大小的变化。地应力重分布主要受到裂缝长度、缝内压力和原始地应力场的影响,裂缝长度和缝内压力增加会增加地应力重定向区域和地应力差值均一化区域的范围,原始地应力差值增大会降低其影响范围。根据地应力重分布机理可以实现对地应力场的人工干扰,实现油藏的有效开发。
In order to study the earth stress redistribution around the individual fracture after water injected and analyze the influencing factor of the redistribution, based on the theory of the fracture mechanics, the distribution solution of the geostress field around the single fracture was analyzed, and the calculating method of the geostress steering and difference was established. And moreover the influences of the fracture length, pressure in the fracture and initial in-situ stress field condition on the redistribution of the in-situ stress field were also analyzed. The results show that the redistribution of the in-situ stress caused by the water injection into the single fracture was mainly displayed in the change of the direction and magnitude of the in-situ stress. The redistribution was mainly influenced by the fracture length, pressure in the fracture and initial in-situ stress field, the increase of the fracture length and pressure in the fracture will enlarge the range of the redirection area and homogenization area of the in-situ stress difference, increasing the initial in-situ stress difference will reduce its influence range. Through the mechanism of the in-situ stress redistribution, the artificial interference to the in-situ stress field can be realized, and furthermore the effective development of the oil reservoir can be realized as well.

关键词(KeyWords)： 裂缝注水;诱导应力;地应力重分布;地应力转向;地应力均一化
water injection in fracture;induced stress;in-situ/earth stress redistribution;in-situ stress steering;in-situ stress homogenization

Abstract:

Keywords:

基金项目(Foundation): “十三五”国家科技重大专项“页岩气渗流规律与气藏工程”(2017ZX05037-001)

作者(Author): 郑永香,刘建军
ZHENG Yongxiang,LIU Jianjun

DOI: 10.19597/j.issn.1000-3754.201812045

参考文献(References)：

• [1]WRIGHT C A,WEIJERS L.Hydraulic fracture reorientation:Does it occur/Does it matter[J].The Leading Edge,2001,20(10):1185-1189.
• [2]WRIGHT C A,CONANT R A,GOLICH G M,et al.Hydraulic fracture orientation and production/injection induced reservoir stress changes in diatomite waterfloods[C]//SPE Western Regional Meeting.Society of Petroleum Engineers,1995.
• [3]HE Q,SUORINENI F T,MA T,et al.Effect of discontinuity stress shadows on hydraulic fracture re-orientation[J].International Journal of Rock Mechanics and Mining Sciences,2017,91:179-194.
• [4]张志强,师永民,卜向前,等.低渗透油藏注水开发中地应力方向变化的研究分析[J].北京大学学报(自然科学版),2016,52(5):861-870.ZHANG Zhiqiang,SHI Yongmin,BU Xiangqian,et al.A study of in-situ stress direction change during waterflooding in the low permeability reservoirs[J].Acta Scientiarum Naturalium Universitatis Pekinensis,2016,52(5):861-870.
• [5]董光,邓金根,朱海燕,等.重复压裂前的地应力场分析[J].断块油气田,2012,19(4):485-488,492.DONG Guang,DENG Jingen,ZHU Haiyan,et al.Analysis of stress field before refracture treatment[J].Fault-Block Oil & Gas Field,2012,19(4):485-488,492.
• [6]邵尚奇,陈凯,丁文刚,等.水力裂缝周围应力场解析模型及应力扰动分析[J].石油机械,2018,46(2):108-114.SHAO Shangqi,CHEN Kai,DING Wengang,et al.Stress field analytic model and stress perturbation analysis around hydraulic cracks[J].China Petroleum Machinery,2018,46(2):108-114.
• [7]OLSON J E.Multi-fracture propagation modeling:Applications to hydraulic fracturing in shales and tight gas sands[C]//The 42nd US Rock Mechanics Symposium (USRMS).American Rock Mechanics Association,2008.
• [8]ROUSSEL N P,SHARMA M M.Optimizing fracture spacing and sequencing in horizontal-well fracturing[J].SPE Production & Operations,2011,26(2):173-184.
• [9]JONATHAN C M,JENNIFER L M.Optimizing hydraulic fracture spacing in unconventional shales[C]//SPE Hydraulic Fracturing Technology Conf.The Woodlands,Texas,USA.2012.
• [10]陈淑利,孙庆和,宋正江.特低渗透裂缝型储层注水开发中后期地应力场变化及开发对策[J].现代地质,2008,22(4):647-654.CHEN Shuli,SUN Qinghe,SONG Zhengjiang.Changes of ground stress field and development policy in later half period of water injection for the extremely low permeability reservoirs with fractures[J].Geoscience,2008,22(4):647-654.
• [11]MEYER B R,BAZAN L W.A discrete fracture network model for hydraulically induced fractures:Theory,parametric and case studies[Z].The Woodlands,Texas,USA,2011.
• [12]MSEKH M A,SARGADO J M,JAMSHIDIAN M,et al.Abaqus implementation of phase-field model for brittle fracture[J].Computational Materials Science,2015,96(Part B):472-484.
• [13]MIEHE C,HOFACKER M,WELSCHINGER F.A phase field model for rate-independent crack propagation:Robust algorithmic implementation based on operator splits[J].Computer Methods in Applied Mechanics and Engineering,2010,199(45-48):2765-2778.
• [14]李世愚,和泰名,尹祥础.岩石断裂力学[M].北京:科学出版社,2016.LI Shiyu,HE Taiming,YIN Xiangchu.Rock fracture mechanics[M].Beijing:Science Press,2016.
• [15]MANCHANDA R,SHARMA M.Impact of completion design on fracture complexity in horizontal shale wells[J].SPE Drilling & Completion,2012,29(29):78-87.