岩石力学参数影响断背斜内张裂缝发育带的概念模型

doi:10.11743/ogg20200302

摘要/Abstract

摘要： 在对库车坳陷克拉苏构造带内断背斜的构造裂缝研究中，发现断背斜内转折端发育张裂缝发育带，且张裂缝发育带的单井测试产量高，是断背斜内的油气高产区，深化研究张裂缝发育带及其影响因素对于油气勘探开发具有重要意义。前期工作发现张裂缝发育带受背斜“中和面”的控制，而岩石力学参数对断背斜内张裂缝发育带的影响还不清楚。因此，以库车坳陷克拉苏构造带内断背斜为背景，通过有限元数值模拟方法，建立了不同岩石力学参数的二维力学概念模型，分析了杨氏模量、泊松比和粘度比对张裂缝发育带的影响。结果表明：在杨氏模量大于70 GPa时，最大应变值随着杨氏模量增大而快速增大；随着杨氏模量的增加，张裂缝发育带的宽度和厚度总体上呈现线性增加的特征。在杨氏模量大于40 GPa条件下，随着泊松比增加，最大应变值和张裂缝发育带的宽度总体上缓慢增加。在粘度比小于25的情况下，最大应变值为0，不存在张裂缝发育带的宽度和张裂缝发育带的厚度；在粘度比大于25的情况下，最大应变值开始大于0且逐渐增大，张裂缝发育带的宽度和张裂缝发育带的厚度都随着粘度比的增加而增加。

关键词: 杨氏模量, 泊松比, 粘度比, 张裂缝发育带, 二维力学, 数值模拟, 断背斜, 库车坳陷

Abstract: The study on the structural fracture development in the faulted anticline in Kelasu tectonic zone,Kuqa Depression,reveals a tensile fracture zone developed in the hinge zone of the faulted anticline.And the flow rate from single-well test in the tensile fracture zone is high,indicating a prolific zone.Therefore,it is of great significance to oil/gas exploration and development to make an in-depth study on the tension fracture zone and its controlling factors.Our previous study reveals that the tensile fracture zone is controlled by neutral surfaces,but the influence of rock mechanics on the zone remains unclear.Then,we build several 2D mechanical conceptual models with different rock mechanical parameters through finite numerical modeling,for analyzing the influence of Young's modulus,Poisson ratio and viscosity ratio on the tensile fracture zone.The results show that:(1) when the Young's modulus is greater than 70 GPa,the maximum strain value grows rapidly with the increasing Young's modulus;both the width and thickness of the zone feature an overall linear growth with the increasing Young's modulus;(2) when the Young's modulus is greater than 40 GPa,the maximum strain value and width of the zone grow progressively with the increasing Poisson ratio;(3) when the viscosity ratio is less than 25,the maximum strain value comes to zero,and the width or thickness of the tensile fracture zone can be neglected;while when the viscosity ratio is greater than 25,the maximum strain value grows greater than zero and increases gradually,and so do the width and thickness of the zone.

Key words: Young's modulus, Poisson ratio, viscosity ratio, tensile fracture zone, 2D mechanics, numerical modeling, faulted anticline, Kuqa Depression

中图分类号:

TE121.1

孙帅,侯贵廷. 岩石力学参数影响断背斜内张裂缝发育带的概念模型[J]. 石油与天然气地质, 2020, 41(3): 455-462. doi: 10.11743/ogg20200302 Sun Shuai,Hou Guiting. Analysis of conceptual models for the influence of rock mechanics on tensile zone in faulted anticlines[J]. Oil & Gas Geology, 2020, 41(3): 455-462. doi: 10.11743/ogg20200302

参考文献

[1] King W.Report on the superinduced divisional structure of rocks,called jointing,and its relation to slaty cleavage[J].The Transactions of the Royal Irish Academy,1875,25:605-662.
[2] Mc Gee W J.Note on Jointed structure[J].American Journal of Science,1883,125:153.
[3] Becker G F.Finite homogeneous strain,flow and rupture of rocks[J].Geological Society of America Bulletin,1892,4(1):13-90.
[4] Pollard D D,Aydin A.Progress in understanding jointing over the past century[J].Geological Society of America Bulletin,1988,100(8):1181-1204.
[5] 周新桂,张林炎,范昆.油气盆地低渗透储层裂缝预测研究现状及进展[J].地质论评,2006,52(6):777-782. Zhou Xingui,Zhang Linyan,Fan Kun,et al.The research situation and progresses of natural fracture for low permeability reservoirs in oil and gas Basin[J].Geological Review,2006,52(6):777-782.
[6] 曾联波,李跃纲,张贵斌,等.川西南部上三叠统须二段低渗透砂岩储层裂缝分布的控制因素[J].中国地质,2007,4:84-89. Zeng Lianbo,Li Yuegang,Zhang Guibin,et al.Controlling factors for fracture distribution in the low-permeability sandstone reservoir of the Second Member of the Upper Triassic Xujiahe Formation in the South of Western Sichuan[J].Geology in China,2007,34(4):84-89.
[7] 杨东兴.东濮凹陷泥页岩油气藏裂缝发育主控因素分析[J].石油地质与工程,2018,32(3):45-47. Yang Dongxing.Main controlling factors of shale reservoir fracture development in Dongpu sag[J].Petroleum Geology & Engineering,2018,32(3):45-47.
[8] 门晶璇,宋哲.沾化凹陷古近系-新近系沉积岩裂缝形成研究[J].石油地质与工程,2018,32(6):45-48. Men Jingxuan,Song Zhe.Fracture formation in Paleogene-Neogene sedimentary rocks of Zhanhua sag[J].Petroleum Geology & Engineering,2018,32(6):45-48.
[9] Zahm C K,Hennings P H.Complex fracture development related to stratigraphic architecture:Challenges for structural deformation prediction,Tensleep Sandstone at the Alcova anticline,Wyoming[J].AAPG Bulletin,2009,93(11):1427-1446.
[10] Ju Wei,Sun Weifeng.Tectonic fractures in the Lower Cretaceous Xiagou Formation of Qingxi Oilfield,Jiuxi Basin,NW China Part one:Characteristics and controlling factors[J].Journal of Petroleum Science and Engineering,2016,146:617-625.
[11] Mc Quillan H.Small-scale fracture density in Asmari Formation of southwest Iran and its relation to bed thickness and structural setting[J].AAPG Bulletin,1973,57(12):2367-2385.
[12] Bai T,Pollard D D.Fracture spacing in layered rocks:a new explanation based on the stress transition[J].Journal of Structural Geology,2000,22(1):43-57.
[13] Underwood C A,Cooke M L,Simo J A,et al.Stratigraphic controls on vertical fracture patterns in Silurian dolomite,northeastern Wisconsin[J].AAPG bulletin,2003,87(1):121-142.
[14] Torabi A,Berg S S.Scaling of fault attributes:A review[J].Marine and Petroleum Geology,2011,28(8):1444-1460.
[15] 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. 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.
[16] 张继标,张仲培,汪必峰,等.塔里木盆地顺南地区走滑断裂派生裂缝发育规律及预测[J].石油与天然气地质,2018,39(5):955-963. Zhang Jibiao,Zhang Zhongpei,Wang Bifeng,et al.Development pattern and prediction of induced fractures from strike-slip faults in Shunnan area,Tarim Basin[J].Oil & Gas Geology,2018,39(5):955-963.
[17] Ju Wei,Hou Guiting,Zhang Bo.Insights into the damage zones in fault-bend folds from geomechanical models and field data[J].Tectonophysics,2014,610:182-194.
[18] Stearns D W.Certain aspects of fracture in naturally deformed rocks[C]//Rock mechanics seminar.Terrestrial Sciences Laboratory Bedford,1968,1:97-118.
[19] Ghosh K,Mitra S.Structural controls of fracture orientations,intensity,and connectivity,Teton anticline,Sawtooth Range,Montana[J].AAPG Bulletin,2009,93(8):995-1014.
[20] Frehner M.The neutral lines in buckle folds[J].Journal of Structural Geology,2011,33(10):1501-1508.
[21] 岳喜伟,戴俊生,王珂.岩石力学参数对裂缝发育程度的影响[J].地质力学学报,2014,4:372-378. Yue Xiwei,Dai junsheng,Wang Ke.Influence of Rock Mechanics Parameters on Developmentof Fractures[J].Journal of Geomechanics,2014,4:372-378.
[22] Liu Xiaolong,Eckert A,Connolly P.Stress evolution during 3D single-layer visco-elastic buckle folding:Implications for the initiation of fractures[J].Tectonophysics,2016,679:140-155.
[23] 陈文滨,姜汉桥,李俊键,等.张裂缝和剪裂缝应力敏感差异对致密砂岩储层产能影响[J].特种油气藏,2018,25(5):146-150. Chen Wenbin,Jiang Hanqiao,Li Junjian,et al.Influence of stress sensitivity difference between tensile and searing cracks on tight gas reservoir productivity[J].Special Oil & Gas Reservoirs,2018,25(5):
[24] Sun Shuai,Hou Guiting,Zheng Chunfang.Fracture zones constrained by neutral surfaces in a fault-related fold:Insights from the Kelasu tectonic zone,KuqaDepression[J].Journal of Structural Geology,2017,104:112-124.
[25] Li Yong,Hou Guiting,Hari K R,et al.The model of fracture development in the faulted folds:The role of folding and faulting[J].Marine and Petroleum Geology,2018,89:243-251.
[26] Sun Shuai,Hou Guiting,Zheng Chunfang.Prediction of tensile fractures in KS2 trap,Kuqa Depression,NW China[J].Marine and Petroleum Geology,2019,101:108-116.
[27] 贾承造.塔里木盆地构造特征与油气聚集规律[J].新疆石油地质,1999,20(3):177-183. Jia Chengzao.Structural characteristics and oil/gas accumulative regularity in Tarim Basin[J].Xinjiang Petroleum Geology,1999,20(3):177-183.
[28] 刘和甫,汪泽成,熊保贤,等.中国中西部中、新生代前陆盆地与挤压造山带耦合分析[J].地学前缘,2000,7(3):55-72. Liu Hefu,Wang Zecheng,Xiong Baoxian,et al.Coupling analysis of mesozoic-cenozoic foreland basin and mountain system in central and western China[J].Earth Science Frontiers,2000,7(3):55-72.
[29] 汤良杰,金之钧,贾承造,等.库车前陆褶皱-冲断带前缘大型盐推覆构造[J].地质学报,2004,78(1):17-25. Tang Liangjie,Jin Zhijun,Jia Chengzao,et al.A large-scale salt nappe complex in the leading edge of the Kuqa foreland fold-thrust belt,Tarim Basin,Northwest China[J].Acta Geologica Sinica,2004,78(1):17-25.
[30] 张惠良,张荣虎,杨海军,等.超深层裂缝-孔隙型致密砂岩储集层表征与评价-以库车前陆盆地克拉苏构造带白垩系巴什基奇克组为例[J].石油勘探与开发,2014,41(2):158-167. Zhang Huiliang,Zhang Ronghu,Yang Haijun,et al.Characterization and evaluation of ultra-deep fracture-pore tight sandstone reservoirs:A case study of Cretaceous Bashijiqike Formation in Kelasu tectonic zone in Kuqa Foreland Basin,Tarim,NW China[J].Petroleum Exploration and Development,2014,41(2):158-167.
[31] 丁中一,钱祥麟,霍红.构造裂缝定量预测的一种新方法-二元法[J].石油与天然气地质,1998,19(1):1-14. Ding Zhongyi,Qian Xianglin,Huohong.A new method for quantitative prediction of tectonic fracture-two factors method[J].Oil & Gas Geology,1998,19(1):1-7.
[32] Zhao Wentao,Hou Guiting.Fracture prediction in the tight-oil reservoirs of the Triassic Yanchang Formation in the Ordos Basin,northern China[J].Petroleum Science,2017,14(1):1-23.