Research on stress state in deep shale reservoirs based on in-situ stress measurement and rheological model
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摘要: 深部泥页岩储层地应力状态的准确确定是页岩气等非常规能源高效开发的关键。综合基于原位地应力测试获得水平最小主应力,建立基于流变模型的地应力剖面,应用成像测井技术确定水平最大主应力方向等,是准确确定泥页岩储层地应力的有效方法。将该研究思路应用于陕西汉中SZ1井,利用水压致裂原地应力测试方法获得储层水平最小主应力值范围为32~41 MPa;利用偶极声波测井数据获得岩石力学参数,结合地壳应变率和储层埋藏史,建立了SZ1井地应力剖面,结果表明牛蹄塘组1950~2025 m深度范围内水平主应力差介于10~15 MPa,水平最小主应力值范围为28~41 MPa,水平最大主应力值范围为47~49 MPa,预测得到的水平最小主应力值与实测结果具有较好的一致性。原地应力实测及流变模型预测结果揭示SZ1井地应力为正断型(Sv>SH>Sh)或正断型与走滑型相结合的应力状态(Sv≈SH>Sh)。水平主应力差随伽玛值的升高而变小,表明地应力剖面与地层岩性具有较好的对应关系。基于成像测井揭示的钻孔诱导张裂隙分布特征,SZ1井水平最大主应力方向约为N74°W,与区域构造应力场方向基本一致。相关结论为准确认识SZ1井目标层地应力状态,以及后期水平井布设及压裂控制等提供了重要依据。Abstract: Accurately determining the stress state in deep shale reservoirs is the key to the efficient development of shale gas and other unconventional energy sources. An effective method to increase the evaluation and calculation accuracy of in-situ stress parameters in a deep shale reservoir is to combine different methods to obtain different stress information, such as obtaining the minimum horizontal principal stress based on the in-situ stress measurement, predicting the magnitudes of horizontal stress difference and the horizontal principal stresses by establishing the stress profile based on the rheological model, and estimating the direction of the maximum horizontal principal stress by the wellbore failure imaging logging. We applied this research idea to Well SZ1 in Hanzhong, Shaanxi Province. The minimum horizontal principal stress obtained by hydraulic fracturing ranged from 32 to 41 MPa; Then, the variation laws of rock rheological parameters with the depth were determined by the rock mechanical parameters obtained from cross-dipole acoustic logging data. And combined with the burial history of the reservoir and the strain rate of the crust, the stress profile of Well SZ1 was established. The results show that the magnitude of horizontal stress difference in the depth range of 1950~2025 m in the Niutitang Formation is between 10~15 MPa, and ranges of the minimum and maximum principal stresses are 28~41 MPa and 47~49 MPa, respectively. The predicted horizontal minimum principal stress values are in good agreement with the measured results. Based on the in situ stress measurement and predicted stress profiles, Well SZ1 is characterized by normal faulting (Sv > SH > Sh)or a combination of normal and strike-slip faulting regimes (Sv≈SH > Sh).The horizontal stress difference decreases with the increase of the gamma value, indicating that the stress profile has a good corresponding relationship with the formation lithology. Based on the distribution characteristics of borehole-induced tensile fractures recorded by imaging logging, the direction of the maximum horizontal principal stress in Well SZ1 is ~N74°W, which is consistent with the direction of the regional tectonic stress field. This study provides an important basis for accurately understanding the in-situ stress state of the target layer of Well SZ1, as well as the later horizontal well layout and fracturing control.
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0. 引言
页岩气泛指以吸附或游离态赋存于暗色泥页岩或高炭质泥页岩中的天然气聚集(Daniel and Bustin, 2008;许长春,2012)。中国页岩气资源丰富、可采储量位居世界首位,但同时面临气藏赋存条件复杂、储层渗透性极低、地质构造运动强烈等一系列难题,创新泥页岩储层改造的理论和方法是高效开发页岩气的有效途径和迫切需求(谢和平等,2016;翟刚毅等,2020)。在泥页岩储层改造中,水平钻井和水力压裂是两项关键技术,也是页岩气开采在近20年的井喷式发展中主要依赖的核心技术(刘曰武等,2019)。钻井和压裂均为力学过程,压裂裂缝和水平井的井壁稳定受地应力控制。因此,储层地应力和岩石力学特性在非常规储层开发中具有很重要的地位,是基础理论研究、水平井网部署、起裂压力预测、压裂缝控制和井壁稳定性分析的重要基础数据(谢和平等,2016;陈勉等,2017;Schultz et al., 2018;Zhou et al., 2020)。地应力的精准确定及其分布规律是页岩气开发中研究的热点和难点。目前国内外对泥页岩储层地应力的评价主要参考常规储层基于弹性模型的评价技术,如测井资料解译、小型压裂测试和室内实验等,而忽略了泥页岩储层流变特性对地应力分布规律的影响,导致评价结果的可靠性和精细度较低(Sone and Zoback, 2014a,2014b;陈勉等, 2017;Ma and Zoback, 2017; 孙东生等,2020)。Sone等在泥页岩蠕变实验的基础上,建立了流变参数与岩石弹性参数之间的对应关系,并应用于泥页岩储层地应力分布规律研究(Sone,2012;Sone and Zoback, 2014a,2014b),但受限于实测数据的缺乏,评价结果的可靠性同样不高。因此,综合多方法研究,包括泥页岩储层地应力实测、蠕变实验、成像测井等,进而建立基于实测数据和流变力学参数的泥页岩储层地应力剖面,是准确获取泥页岩储层地应力的有效方法。
中国页岩气的主要富集地区集中在南方海相页岩地层,已先后建立了四川长宁-威远、重庆涪陵等多个国家级页岩气示范区,除此以外,陆相沉积盆地也具备页岩气富集的基础和条件,如松辽、鄂尔多斯等(薛浩和高华新,2013;谢和平等,2016)。近年来,随着国际地学界对造山带边缘及其外侧的逆冲推覆带油气的逐步重视和新的研究成果的不断涌现,国内也适时地加大了造山带前缘盆地交接区的研究勘查力度,位于松潘—甘孜造山带、秦岭造山带和扬子板块交汇部位的米仓山—汉南隆起即是页岩气富集条件勘查区之一。采用水压致裂地应力测试方法,在该区SZ1井开展了原位地应力测试,获得了目标层水平最小主应力值,根据成像测井资料,利用孔壁破坏信息确定了主应力方向;同时根据基于流变参数的水平最大主应力计算模型,结合偶极声波测井结果,计算了水平主应力差及水平最大主应力量值。相关结论为准确认识SZ1井目标层地应力状态,以及后期水平井布设及压裂控制等提供了重要地应力参数依据。
1. 区域地质构造背景
米仓山-汉南隆起位于扬子板块西北缘,处于秦岭造山带和四川盆地之间的构造耦合部位,与构造活跃的青藏高原东缘相接。研究区经历了多期构造运动的影响与改造:早古生代,在加里东期、海西—印支期南北向强烈构造挤压应力作用下,扬子板块西北缘形成以逆冲推覆和宽缓褶皱为主的构造形态,以基底为核部,形成汉南等穹隆构造;进入中生代以来,在印支—燕山期多期次构造运动改造下,由造山带到盆缘形成叠瓦冲断带、逆冲扩展变形带、低缓褶皱带、前陆盆地等变形格局与变形特征,且由造山带向四川盆地,变形强度由强变弱(邓明森,1997;董云鹏等,2008;王宗起等,2009;常远等,2010;李华兵等,2019;张国伟等,2019;田涛等,2020;张晓琪等,2021);新生代以来,受周边地块不均匀的构造挤压和拉伸作用影响,研究区壳幔结构作用强烈,秦岭造山带不仅是青藏高原物质东逸的岩石圈挤出通道,还可能是软流圈东流的地幔流通道(危自根等,2019;常利军等,2021)。与具有复杂新生代构造和强烈的地壳运动以及地震活动的青藏高原相比,研究区地震活动较弱,历史地震多受断裂控制(图 1a),GPS数据显示,研究区与周边区域地壳运动特征一致,并且最大主应变率很小,约(-0.2~0.1)×10-9/a(Wang and Shen, 2020)。
SZ1井位于陕西汉中镇巴县,所处大地构造位置为米仓山隆起东缘,寒武系牛蹄塘组为目标勘探层位。米仓山隆起长期以来受青藏高原隆升、秦岭造山带和龙门山造山带演化的共同影响,其东西部为宽缓的倾伏背斜,北部为回军坝向斜,紧邻汉南隆起带,南部经过平缓变形区进入四川盆地(张文军等, 2016; 李华兵等, 2019)。研究区所处构造单元为南秦岭-龙门山前陆褶冲带(王宗起等, 2009),发育近东西向和近北东向两组构造体系,包括板缘断裂和板内断裂等多种类型(图 1b),受区内强烈挤压构造应力作用,断裂活动多以逆断型为主。区内地层以古生界和中生界为主,也有少量前寒武系出露。下奥陶统以赵家坝组灰绿色页岩、含砂质页岩为主;下寒武统牛蹄塘组不整合于上震旦统灯影组灰白色细晶白云岩之上,下寒武统石牌组灰绿色页岩、粉砂质页岩之下。牛蹄塘组下部主要为黑色微细层状含硅质炭质页岩;中部以黑色微细层钙质炭质页岩、钙质页岩为主;上部为灰黑色微细层状钙质砂质页岩(李华兵等,2019;张欣等,2010)。页岩气调查井和露头剖面实测揭露区内牛蹄塘组页岩厚度普遍超过100 m(田涛等,2020)。
2. 水压致裂地应力测试确定水平最小主应力
2.1 测点概况及测试方法概述
SZ1井水压致裂地应力测试深度范围均位于牛蹄塘组,岩性为黑色炭质页岩。钻探实际揭露牛蹄塘组深度范围1950~2025 m,参考测井资料,结合水平井层位和压裂改造需求,确定压裂段中心深度分别为1956 m、1968 m、1982 m和1995 m(图 2)。
自20世纪30年代开始地应力测试以来,至今已有数十种地应力测试方法得到发展(Zang and Stephansson, 2010)。其中水压致裂法以操作简单、可直接确定最小水平主应力、不需要岩石力学参数参与计算、测试深度理论上不受限制等优势成为国际岩石力学学会试验方法委员会(ISRM)建议的确定岩体应力的方法之一(Haimson et al., 1978, 2003),并且在深部资源能源开发、地下空间利用、地球动力学研究等领域得到广泛的应用(张鹏等,2017;陈群策等,2019;Meng et al., 2015;Zoback,2007)。然而,尽管水压致裂法是测试深部地应力状态的最有效的方法,但由于测试系统柔度的影响,压裂参数的取值以及相应的主应力计算结果的准确性往往受到影响(Ito et al., 1999; 秦向辉等, 2020)。采用最新研发的大口径深孔地应力测试设备(孙东生等,2018;陈群策等,2019),同时监测井下压裂段的压力变化,获得压裂段压力-时间曲线,有效减小了系统柔度对压力参数的干扰。测试过程严格按照ISRM颁布的规范进行,压裂曲线形态符合ISRM要求(图 3)。
由于水压致裂地应力测试方法确定水平最大主应力(SH)是基于岩石符合线弹性力学性质的假设,而本次测试段为泥页岩地层,岩石的塑性特征较强,根据传统计算公式获得的水平最大主应力值可能存在较大的误差。而水压致裂地应力测试方法是基于压裂缝闭合时的流体压力确定水平最小主应力(Sh),故虽为基于线弹性理论模型的地应力测试方法,仍可用于确定强流变软岩地层的水平最小主应力,因此SZ1井水压致裂地应力测量仅能获得准确的测试段的水平最小主应力值。压裂参数取值同样采用ISRM标准,其中瞬时关闭压力PS分别采用单切线法、dt/dP法和dP/dt法三种方法(Haimson, 2003; 丰成君等, 2012)。为了尽可能获得高精度的应力值结果,对每一测段每一重张回次均进行了取值,并取各方法的平均值参与主应力值的计算,结果如表 1。垂向主应力的取值依据式:Sv=γh,由上覆岩层重量取得,其中h为地面至压裂段中心点的深度,岩石容重γ根据密度测井结果,取值为25.00 kN/m3。
表 1 SZ1井水压致裂原地应力测试结果Table 1. In situ stress measurement results of Well SZ1 using the hydraulic fracturing method深度/m 压裂参数/MPa 主应力/MPa Pb 回次 Ps取值 Ps终值 Ps标准差 Sh Sv dt/dP法 dP/dt法 切线法 均值 1956 43.02 cycle-1 39.34 38.94 39.12 39.13 38.22 0.79 38.22 48.90 cycle-2 38.15 37.38 38.39 37.97 cycle-3 37.71 37.1 37.84 37.55 1968 47.10 cycle-1 41.10 40.96 41.88 41.31 40.43 1.21 40.43 49.20 cycle-2 40.42 41.97 40.56 40.98 cycle-3 39.11 38.47 39.43 39.00 1982 41.74 cycle-1 34.77 34.66 34.29 34.57 33.63 1.04 33.63 49.55 cycle-2 34.17 33.34 33.99 33.83 cycle-3 33.07 31.53 32.87 32.49 1995 40.85 cycle-1 31.51 31.14 32.04 31.56 32.28 0.80 32.28 49.88 cycle-2 33.21 33.37 33.18 33.25 cycle-3 32.12 32.18 31.77 32.02 注:Pb—破裂压力;Ps—瞬时关闭压力;Sh—水平最小主应力;Sv—垂向主应力 2.2 水平最小主应力
根据测试结果,SZ1井在1956~1995 m的深度范围内,水平最小主应力值在32~41 MPa之间,且随深度增加没有明显的线性分布规律(图 4)。
根据断层几何形态以及产生断层的应力关系,断层可以划分为三个基本类型,即正断层、走滑断层和逆断层,不同性质的断层所对应的应力结构及震源机制解不同,分别为:正断型断层,Sv>SH>Sh;走滑型断层,SH>Sv>Sh;逆断型断层,SH>Sh>Sv,不同的应力结构会引发不同性质的断层活动(Anderson, 1951;Jaeger and Cook, 1969)。SZ1井基于水压致裂测试获得的水平最小主应力,均小于通过上覆岩体重量计算获得的垂向应力,因此,SZ1井在测试深度范围内应力结构应以走滑型或者正断型为主。
3. 孔壁破坏信息确定主应力方向
地壳岩体中的应力状态是非均匀性的,当钻孔成形后,在最小主应力方向上由于钻孔周围应力集中而导致钻孔孔壁岩体崩落破坏形成钻孔崩落(BO),而在最大主应力方向上当岩体张应力集中水平超过孔壁岩体抗拉强度时则产生诱发张裂隙(DITF)(Bell and Gough, 1979;Pöppelreiter,2010;陈念等,2021)。因此钻孔崩落的长轴方向对应水平最小主应力方向,孔壁诱发裂隙走向则与水平最大主应力方向一致。高精度超声波钻孔成像能够有效识别岩体中钻孔孔壁细微结构,进而提供深部岩体真实可靠的地应力方向信息。钻孔崩落与诱发张裂隙大多情况下并不会同时出现,根据SZ1井成像测井结果,在泥页岩储层深度范围内未揭露钻孔崩落现象,但具有明显的钻井诱发张裂隙。根据诱导张裂缝信息,裂缝呈不连续分布,近竖直,呈近180°对称(图 5),据此确定水平最大主应力为近N74°W方向。
根据中国构造应力场分布及分区特征(图 6),研究区主体位于华南主体应力区西北角,同时受西秦岭应力区和龙门山-松潘应力区影响。华南主体应力区主要受到菲律宾板块向北西西方向碰撞和青藏块体向东南方向挤出的联合作用,最大主压应力方向为北西—南东向,应力结构以正断型和走滑型为主。SZ1井实测主应力方向与区域构造应力场方向基本一致,且耦合于地表形变测量结果(Wang and Shen, 2020)。
a—基于2016年WSM数据库发布的中国及周边地区应力图;b—中国构造应力分区图;c—研究区应力图(数据获取方法为水压致裂地应力测试方法).Figure 6. Regional stress map (Hu et al., 2017; Heidbach, et al., 2016; Xie et al., 2004; Yang et al., 2012; Xie and Cui, 2015)(a)Stress map of China and its adjacent areas based on the WSM database released in 2016; (b) Tectonic stress zoning in China; (c)Stress map of the study area based on the hydraulic fracturing method地应力是控制泥页岩储层压裂过程中裂缝网络形成的主要因素之一。当水平井定向与水平最小主应力方向一致时,与水平井筒垂直的射孔将沿水平最大主应力方向进行,可以产生与井筒垂直的多条人工裂缝。而当水平井沿水平最大主应力方向定向时,则易形成单一的水力裂缝。此外,在正断型应力结构下,水平井沿水平最小主应力方向布设时需要最大的起裂压力(Hossain et al., 2000;Huang et al., 2012)。基于原位地应力测试揭示了SZ1井泥页岩储层以正断型和走滑型应力结构为主,因此,在后期布设水平井时,应综合考虑起裂压力及复杂裂缝形成。此外,由于垂向应力为最大主应力,压裂裂缝的总体形态逐渐趋向于沿最大主应力方向扩展,即由近水平变为近垂直。因此,后期需要对压裂裂缝的延伸方向进行干预。
4. 流变模型建立地应力剖面
实践证明地应力大小与赋存地层的岩性具有明显的对应关系。Sone and Zoback(2014a, 2014b)根据页岩储层地应力分布特征,提出了一种利用流变模型预测水平主应力差的方法,在恒定应变率构造载荷作用下,水平主应力差随时间积累的理论模型如下:
S(t)=˙ε⋅1B(1−n)⋅t1−n (1) 其中S(t)表示水平主应力差,MPa;˙ε表示岩石地层所在板块的平均地壳应变速率,按10-19s-1计算以代表稳定的板内变形(Zoback and Townend, 2001;Sone and Zoback, 2014a);B和n表示幂律本构参数,其中B本质上反映了岩石的瞬时弹性特性,可近似为弹性模量的倒数,即B=1/E,MPa-1,n为描述随时间变化的变形趋势的参数,介于0.01至0.08之间,可近似表示为参数B的函数,n=2000B/3(Sone, 2012);t表示泥页岩成岩作用开始到现今埋藏史,寒武纪距今约500 Ma年,参考Sone(2012)埋藏史取值办法,取地质演化史的一半250 Ma进行计算。
利用上述流变模型计算得到的SZ1井水平主应力差随深度的变化剖面(图 7)。结果表明,SZ1井牛蹄塘组储层内水平主应力差介于10~15 MPa之间,且水平主应力差值随伽玛值(有机质含量和黏土矿物含量)的升高而减小。地应力剖面与地层岩性具有较强的相关性,反映了泥页岩储层经过漫长的地质历史时期,由于其流变特性,储层水平最大和最小主应力量值在区域构造应力场作用下逐渐趋于一致。因此对于页岩气等非常规油气储层,由于富含有机质和黏土矿物,岩石的流变特性增强,地层应力场各向异性逐渐减弱,三向主应力趋于一致(Sone, 2012;刘合等,2019;孙东生等,2020)。
5. 讨论
利用式(1)流变模型可以得到水平主应力差的深度剖面(图 7c、7f),据此可以进一步得到水平最小主应力和水平最大主应力的深度剖面。根据SZ1井原地应力测试结果,在测试深度范围内应力结构应以走滑型或者正断型为主(图 4),假设整个沉积层中应力结构保持不变,那么水平主应力和垂向应力之间的关系即为SH>Sv>Sh,或Sv>SH>Sh。利用参数φ表示主应力比值(Angelier, 1979;Sone and Zoback, 2014b):
φ=(S2−S3)/(S1−S3) (2) 其中S1>S2>S3,假设φ值随深度保持不变,在走滑型应力结构(SS)条件下,根据水平主应力差值和φ值可以计算得到水平主应力值:
Sh=Sv−φ(SH−Sh)SH=Sv+(1−φ)(SH−Sh) (3) 同理,在正断型应力结构(NF)条件下,水平主应力值计算公式为:
Sh=Sv−(SH−Sh)/φSH=Sv+(φ−1)(SH−Sh)/φ (4) 根据原位地应力测试结果及流变模型估算得到的水平主应力差,可以推算φ值在0.5~1.0之间。分别取φ=0.6和φ=0.9,计算得到走滑型应力结构和正断型应力结构条件下的四条主应力值剖面(图 8)。根据计算结果可知,φ=0.6时基于流变模型预测得到的水平最小主应力值与原地应力测试得到的结果差别较大,而φ=0.9时两者较为相近。同时,φ=0.9的前提下,走滑型应力结构和正断型应力结构条件下预测得到的水平主应力剖面形态较为相似,且两者相比,正断型应力结构条件下,预测结果与实测结果一致性更好。因此,SZ1井地应力为正断型(Sv>SH>Sh)或正断型与走滑型结合的状态(Sv≈SH>Sh)。
图 8 主应力值随深度变化剖面(黑色水平短线代表水压致裂地应力测试确定的水平最小主应力范围)a—走滑型应力结构条件下,φ=0.6计算得到的主应力剖面;b—正断型应力结构条件下,φ=0.6计算得到的主应力剖面;c—走滑型应力结构条件下,φ=0.9计算得到的主应力剖面;d—正断型应力结构条件下,φ=0.9计算得到的主应力剖面Figure 8. Principal stress varies with depth (Black horizontal bars indicate the range of horizontal stress magnitudes obtained by in situ stress measurement)(a)Stress profile for stress ratio φ=0.6 within the strike-slip faulting regime; (b) Stress profile for stress ratio φ=0.6 within the normal faulting regime; (c) Stress profile for stress ratio φ=0.9 within the strike-slip faulting regime; (a) Stress profile for stress ratio φ=0.9 within the normal faulting regime此外,牛蹄塘组深度范围内,水平最小主应力值相比石牌组和灯影组呈增加的趋势,与水平主应力差值具有相似的分布特征,即随伽玛值(有机质含量和黏土矿物含量)的升高而增大(图 7,图 8)。因此,受黏土和有机质等塑性矿物含量的影响,由于黏塑性应力松弛,泥页岩储层水平最小主应力明显高于脆性地层,水平主应力差变小,水平应力各向异性减小(Sone and Zoback, 2014b;Ma and Zoback, 2017)。主应力比值决定了压裂时裂缝的破裂及空间展布形式,谢和平等(2016)认为当水平应力比(SH/Sh)小于1.9时,容易出现多裂缝起裂的现象,裂缝的密度和迂曲度更大。基于SZ1井水压致裂地应力测试及流变模型(NF, φ=0.9)预测,揭示泥页岩储层水平最小主应力值范围为28~41 MPa,水平最大主应力值范围为47~49 MPa,水平应力比介于1.15~1.75之间,易形成多裂缝体系。
6. 结论
综合基于原位地应力测试获得水平最小主应力,通过建立基于流变模型的地应力剖面获得水平最大主应力,应用成像测井技术确定水平最大主应力方向等,详细分析了陕西汉中SZ1井泥页岩储层地应力状态。
(1) 水压致裂地应力测试结果表明SZ1井水平最小主应力值在32~41 MPa之间,均小于垂向主应力。
(2) 考虑泥页岩储层流变特性,结合偶极声波测井数据,建立了SZ1井地应力剖面,结果表明牛蹄塘组1950~2025 m深度范围内水平主应力差介于10~15 MPa之间,水平最小主应力值范围为28~41 MPa,水平最大主应力值范围为47~49 MPa。基于流变模型的地应力预测剖面与实测结果具有较好的一致性。
(3) 基于原地应力测试及流变模型预测得到的主应力剖面,SZ1井牛蹄塘组泥页岩储层为正断型或正断型与走滑型相结合的应力状态。
(4) 水平最小主应力值随伽马值的升高而增加,水平主应力差则随伽玛值的升高而减小,表明地应力剖面与地层岩性具有较高的相关性,泥页岩储层水平最大和最小主应力量值在区域构造应力场作用下逐渐趋于一致。
(5) 基于成像测井记录的钻孔诱导张裂隙分布特征,SZ1井水平最大主应力方向约为N74°W,与区域构造应力场方向基本一致,主要受到菲律宾板块北西西向碰撞和青藏块体东南向挤出的联合作用。
责任编辑:王婧 -
图 6 区域构造应力场分布图(Hu et al., 2017;Heidbach et al., 2016;谢富仁等,2004;杨树新等,2012;谢富仁和崔效锋,2015)
a—基于2016年WSM数据库发布的中国及周边地区应力图;b—中国构造应力分区图;c—研究区应力图(数据获取方法为水压致裂地应力测试方法).
Figure 6. Regional stress map (Hu et al., 2017; Heidbach, et al., 2016; Xie et al., 2004; Yang et al., 2012; Xie and Cui, 2015)
(a)Stress map of China and its adjacent areas based on the WSM database released in 2016; (b) Tectonic stress zoning in China; (c)Stress map of the study area based on the hydraulic fracturing method
图 8 主应力值随深度变化剖面(黑色水平短线代表水压致裂地应力测试确定的水平最小主应力范围)
a—走滑型应力结构条件下,φ=0.6计算得到的主应力剖面;b—正断型应力结构条件下,φ=0.6计算得到的主应力剖面;c—走滑型应力结构条件下,φ=0.9计算得到的主应力剖面;d—正断型应力结构条件下,φ=0.9计算得到的主应力剖面
Figure 8. Principal stress varies with depth (Black horizontal bars indicate the range of horizontal stress magnitudes obtained by in situ stress measurement)
(a)Stress profile for stress ratio φ=0.6 within the strike-slip faulting regime; (b) Stress profile for stress ratio φ=0.6 within the normal faulting regime; (c) Stress profile for stress ratio φ=0.9 within the strike-slip faulting regime; (a) Stress profile for stress ratio φ=0.9 within the normal faulting regime
表 1 SZ1井水压致裂原地应力测试结果
Table 1. In situ stress measurement results of Well SZ1 using the hydraulic fracturing method
深度/m 压裂参数/MPa 主应力/MPa Pb 回次 Ps取值 Ps终值 Ps标准差 Sh Sv dt/dP法 dP/dt法 切线法 均值 1956 43.02 cycle-1 39.34 38.94 39.12 39.13 38.22 0.79 38.22 48.90 cycle-2 38.15 37.38 38.39 37.97 cycle-3 37.71 37.1 37.84 37.55 1968 47.10 cycle-1 41.10 40.96 41.88 41.31 40.43 1.21 40.43 49.20 cycle-2 40.42 41.97 40.56 40.98 cycle-3 39.11 38.47 39.43 39.00 1982 41.74 cycle-1 34.77 34.66 34.29 34.57 33.63 1.04 33.63 49.55 cycle-2 34.17 33.34 33.99 33.83 cycle-3 33.07 31.53 32.87 32.49 1995 40.85 cycle-1 31.51 31.14 32.04 31.56 32.28 0.80 32.28 49.88 cycle-2 33.21 33.37 33.18 33.25 cycle-3 32.12 32.18 31.77 32.02 注:Pb—破裂压力;Ps—瞬时关闭压力;Sh—水平最小主应力;Sv—垂向主应力 -
ANDERSON E M, 1951. The dynamics of faulting and Dike formation with application to Britain[M]. 2nd ed. Edinburgh, U.K. : Oliver and Boyd. ANGELIER J, 1979. Determination of the mean principal directions of stresses for a given fault population[J]. Tectonophysics, 56(3-4): T17-T26. doi: 10.1016/0040-1951(79)90081-7 BELL J S, GOUGH D I, 1979. Northeast-southwest compressive stress in Alberta evidence from oil wells[J]. Earth and Planetary Science Letters, 45(2): 475-482. doi: 10.1016/0012-821X(79)90146-8 CHANG L J, DING Z F, WANG C Y, 2021. Upper mantle anisotropy and implications beneath the central and western North China and the NE margin of Tibetan Plateau[J]. Chinese Journal of Geophysics, 64(1): 114-130. (in Chinese with English abstract) CHANG Y, XU C H, REINERS P W, et al., 2010. The exhumation evolution of the Micang Shan-Hannan uplift since Cretaceous: Evidence from apatite (U-Th)/He dating[J]. Chinese Journal of Geophysics, 53(4): 912-919. (in Chinese with English abstract) CHEN M, JIN Y, LU Y H, 2017. Shale gas development: Opportunities and challenges for rock mechanics[J]. Scientia Sinica: Physica, Mechanica & Astronomica, 47(11): 114601. (in Chinese with English abstract) CHEN N, WANG C H, CHEN P Z, et al., 2021. Re-analyzing the in-situ stress field in the right bank of the Baihetan hydroelectric power plant using the borehole breakout data[J]. Journal of Geomechanics, 27(3): 430-440, doi: 10.12090/j.issn.1006-6616.2021.27.03.039. CHEN Q C, SUN D S, CUI J J, et al., 2019. Hydraulic fracturing stress measurements in Xuefengshan deep borehole and its significance[J]. Journal of Geomechanics, 25(5): 853-865. (in Chinese with English abstract) DENG M S, 1997. Deformational analysis of the fold structure of sedimentary cover in Micangshan area[J]. Journal of Mineralogy and Petrology, 17(S1): 132-142. (in Chinese with English abstract) DONG Y P, ZHA X F, FU M Q, et al., 2008. Characteristics of the Dabashan fold-thrust nappe structure at the southern margin of the Qinling, China[J]. Geological Bulletin of China, 27(9): 1493-1508. (in Chinese with English abstract) FENG C J, CHEN Q C, WU M L, et al., 2012. Analysis of hydraulic fracturing stress measurement data: discussion of methods frequently used to determine instantaneous shut-in pressure[J]. Rock and Soil Mechanics, 33(7): 2149-2159. (in Chinese with English abstract) HAIMSON B C, 1978. The hydrofracturing stress measuring method and recent field results[J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 15(4): 167-178. HAIMSON B C, CORNET F H, 2003. ISRM Suggested Methods for rock stress estimation-Part 3: hydraulic fracturing (HF) and/or hydraulic testing of pre-existing fractures (HTPF)[J]. International Journal of Rock Mechanics and Mining Sciences, 40(7-8): 1011-1020. doi: 10.1016/j.ijrmms.2003.08.002 HEIDBACH O, RAJABI M, REITER K, et al., 2016. World stress map database release 2016[DB/OL]. GFZ Data Services. https://doi.org/10.5880/WSM.2016.001. HOSSAIN M M, RAHMAN M K, RAHMAN S S, 2000. Hydraulic fracture initiation and propagation: roles of wellbore trajectory, perforation and stress regimes[J]. Journal of Petroleum Science and Engineering, 27(3-4): 129-149. doi: 10.1016/S0920-4105(00)00056-5 HU X P, ZANG A, HEIDBACH O, et al., 2017. Crustal stress pattern in China and its adjacent areas[J]. Journal of Asian Earth Sciences, 149: 20-28. doi: 10.1016/j.jseaes.2017.07.005 HUANG J S, GRIFFITHS D V, WONG S W, 2012. Initiation pressure, location and orientation of hydraulic fracture[J]. International Journal of Rock Mechanics and Mining Sciences, 49: 59-67. doi: 10.1016/j.ijrmms.2011.11.014 ITO T, EVANS K, KAWAI K, et al., 1999. Hydraulic fracture reopening pressure and the estimation of maximum horizontal stress[J]. International Journal of Rock Mechanics and Mining Sciences, 36(6): 811-826. doi: 10.1016/S0148-9062(99)00053-4 JAEGER J C, COOK N G W, 1969. Fundamentals of rock mechanics[M]. London: Methuen & Co. : 513. LI H B, WANG Z, XU F, et al., 2019. Shale gas reservoirs characteristics of Micang Mountain uplift in the north of the Sichuan Basin[J]. Unconventional Oil & Gas, 6(6): 1-6. (in Chinese with English abstract) LI Y F, FU Y Q, TANG G, 2012. Laws of the effects of earth stress patterns on wellbore stability in a directional well[J]. Natural Gas Industry, 32(3): 78-80, 130-131. (in Chinese with English abstract) LIU H, MENG S W, SU J, et al., 2019. Reflections and suggestions on the development and engineering management of shale gas fracturing technology in China[J]. Natural Gas Industry, 39(4): 1-7. (in Chinese with English abstract) LIU Y W, GAO D P, LI Q, et al., 2019. Mechanical frontiers in shale-gas development[J]. Advances in Mechanics, 49(1): 201901. (in Chinese with English abstract) MA X D, ZOBACK M D, 2017. Lithology-controlled stress variations and pad-scale faults: A case study of hydraulic fracturing in the Woodford Shale, Oklahoma[J]. Geophysics, 82(6): ID35-ID44. doi: 10.1190/geo2017-0044.1 MENG W, CHEN Q C, ZHAO Z, et al., 2015. Characteristics and implications of the stress state in the Longmen Shan fault zone, eastern margin of the Tibetan Plateau[J]. Tectonophysics, 656: 1-19. doi: 10.1016/j.tecto.2015.04.010 PÖPPELREITER M, CARMEN G C, KRAAIJVELD M, 2010. Borehole image log technology: application across the exploration and production life cycle[M]//PÖPPELREITER M, GARCÍA-CARBALLIDO C, KRAAIJVELD M. Dipmeter and borehole image log technology. Denver, CO, USA: American Association of Petroleum Geologists: 81-112. QIN X H, CHEN Q C, ZHAO X G, et al., 2020. Experimental study on the crucial effect of test system compliance on hydraulic fracturing in-situ stress measurements[J]. Chinese Journal of Rock Mechanics and Engineering, 39(6): 1189-1202. (in Chinese with English abstract) ROSS D J K, BUSTIN R M, 2008. Characterizing the shale gas resource potential of Devonian-Mississippian strata in the western Canada sedimentary basin: Application of an integrated formation evaluation[J]. AAPG Bulletin, 92(1): 87-125. doi: 10.1306/09040707048 SCHULTZ R, ATKINSON G, EATON D W, et al., 2018. Hydraulic fracturing volume is associated with induced earthquake productivity in the Duvernay play[J]. Science, 359(6373): 304-308. doi: 10.1126/science.aao0159 SONE H, 2012. Mechanical properties of shale gas reservoir rocks, and its relation to the in-situ stress variation observed in shale gas reservoirs[D]. Stanford: Stanford University: 97-189. SONE H, ZOBACK M D, 2014a. Time-dependent deformation of shale gas reservoir rocks and its long-term effect on the in situ state of stress[J]. International Journal of Rock Mechanics and Mining Sciences, 69: 120-132. doi: 10.1016/j.ijrmms.2014.04.002 SONE H, ZOBACK M D, 2014b. Viscous relaxation model for predicting least principal stress magnitudes in sedimentary rocks[J]. Journal of Petroleum Science and Engineering, 124: 416-431. doi: 10.1016/j.petrol.2014.09.022 SUN D S, CHEN Q C, LI A W, 2018-10-19. A waterway switch and packer control device: CN, 106761556B[P]. (in Chinese) SUN D S, PANG F, LI A W, et al., 2020. In-situ stress profile prediction based on the rheological model: A case study of Well AY-1 in the Qianbei area of Guizhou province[J]. Natural Gas Industry, 40(3): 58-64. (in Chinese with English abstract) TIAN T, FU D L, ZHOU S X, et al., 2020. The paleo-redox conditions of the shale in Niutitang Formation and its effects on organic matter enrichment of the Micangshan-Hannan Uplift[J]. Journal of Lanzhou University: Natural Sciences, 56(1): 37-47, 55. (in Chinese with English abstract) WANG M, SHEN Z K, 2020. Present-day crustal deformation of continental China derived from GPS and its tectonic implications[J]. Journal of Geophysical Research: Solid Earth, 125(2): e2019JB018774. WANG Z Q, YAN Q R, YAN Z, et al., 2009. New division of the main tectonic units of the Qinling Orogenic belt, Central China[J]. Acta Geologica Sinica, 83(11): 1527-1546. (in Chinese with English abstract) WEI Z G, CHU R S, YANG X L, et al., 2019. Crustal structure and seismic activity in the Hanzhong basin and its adjacent areas[J]. Acta Seismologica Sinica, 41(4): 445-458. (in Chinese with English abstract) XIE F R, CUI X F, ZHAO J T, et al., 2004. Regional division of the recent tectonic stress field in China and adjacent areas[J]. Chinese Journal of Geophysics, 47(4): 654-662. (in Chinese with English abstract) XIE F R, CUI X F, 2015. Stress map of the recent tectonic stress field in China and adjacent areas[Z]. Beijing: Sino Maps Press. (in Chinese) XIE H P, GAO F, JU Y, et al., 2016. Novel idea of the theory and application of 3D volume fracturing for stimulation of shale gas reservoirs[J]. Chinese Science Bulletin, 61(1): 34-46. (in Chinese with English abstract) doi: 10.1360/zk2016-61-1-34 XU C C, 2012. Research progress in shale gas geological theory in China[J]. Special Oil & Gas Reservoirs, 19(1): 9-16. (in Chinese with English abstract) XUE H, GAO H X, 2013. Introduction to the current situation and future of shale gas in China[J]. Shanghai Energy Conservation(9): 9-13. (in Chinese) YANG S X, YAO R, CUI X F, et al., 2012. Analysis of the characteristics of measured stress in Chinese mainland and its active blocks and North-South seismic belt[J]. Chinese Journal of Geophysics, 55(12): 4207-4217. (in Chinese with English abstract) ZANG A, STEPHANSSON O, 2010. Stress field of the Earth' s crust[M]. Dordrecht: Springer. ZHAI G Y, WANG Y F, LIU G H, et al., 2020. Accumulation model of the Sinian-Cambrian shale gas in western Hubei Province, China[J]. Journal of Geomechanics, 26(5): 696-713. ZHANG G W, GUO A L, DONG Y P, et al., 2019. Rethinking of the Qinling orogen[J]. Journal of Geomechanics, 25(5): 746-768. (in Chinese with English abstract) ZHANG P, SUN Z G, WANG Q N, et al., 2017. In-situ stress measurement and stability analysis of surrounding rocks in the north section of deep buried tunnel in Muzhailing[J]. Journal of Geomechanics, 23(6): 893-903. (in Chinese with English abstract) ZHANG W J, QIN X Q, GAO T J, et al., 2016. Characteristics and Evolution of Middle Cenozoic Tectonics, Micangshan Uplift Belt[J]. Natural gas technology and economy, 10(2): 22-25, 33. (in Chinese with English abstract) ZHANG X, 2010. The dynamic mechanism and geological significance of mafic intrusion in the Ziyang-Zhenba Area, South Qinling[D]. Xi' an: Chang' an University. ZHANG X Q, ZHAO D C, LI Z Z X, et al., 2021. The implications of three stages of Tonian magmatism in the northwestern margin of the Yangtze Block on the breakup of the Rodinia supercontinent[J]. Journal of Northwest University (Natural Science Edition), 51(6): 1042-1056. (in Chinese with English abstract) ZHOU Z, JIN Y, ZENG Y J, et al., 2020. Investigation on fracture creation in hot dry rock geothermal formations of China during hydraulic fracturing[J]. Renewable Energy, 153: 301-313. doi: 10.1016/j.renene.2020.01.128 ZOBACK M D, TOWNEND J, 2001. Implications of hydrostatic pore pressures and high crustal strength for the deformation of intraplate lithosphere[J]. Tectonophysics, 336(1-4): 19-30. doi: 10.1016/S0040-1951(01)00091-9 ZOBACK M D, 2007. Reservoir geomechanics[M]. New York: Cambridge University Press: 1-505. 常利军, 丁志峰, 王椿镛, 2021. 华北中西部和青藏高原东北缘上地幔各向异性变形特征[J]. 地球物理学报, 64(1): 114-130. https://www.cnki.com.cn/Article/CJFDTOTAL-DQWX202101008.htm 常远, 许长海, REINERS P W, 等, 2010. 米仓山-汉南隆起白垩纪以来的剥露作用: 磷灰石(U-Th)/He年龄记录[J]. 地球物理学报, 53(4): 912-919. doi: 10.3969/j.issn.0001-5733.2010.04.016 陈勉, 金衍, 卢运虎, 2017. 页岩气开发: 岩石力学的机遇与挑战[J]. 中国科学: 物理学 力学 天文学, 47(11): 114601. https://www.cnki.com.cn/Article/CJFDTOTAL-JGXK201711002.htm 陈念, 王成虎, 陈平志, 等, 2021. 利用钻孔崩落数据再认识白鹤滩右岸地应力场特征[J]. 地质力学学报, 27(3): 430-440, doi: 10.12090/j.issn.1006-6616.2021.27.03.039. 陈群策, 孙东生, 崔建军, 等, 2019. 雪峰山深孔水压致裂地应力测量及其意义[J]. 地质力学学报, 25(5): 853-865. doi: 10.12090/j.issn.1006-6616.2019.25.05.070 邓明森, 1997. 米仓山区盖层褶皱构造变形分析[J]. 矿物岩石, 17(S1): 132-142. https://www.cnki.com.cn/Article/CJFDTOTAL-KWYS7S1.015.htm 董云鹏, 查显峰, 付明庆, 等, 2008. 秦岭南缘大巴山褶皱-冲断推覆构造的特征[J]. 地质通报, 27(9): 1493-1508. doi: 10.3969/j.issn.1671-2552.2008.09.011 丰成君, 陈群策, 吴满路, 等, 2012. 水压致裂应力测量数据分析: 对瞬时关闭压力ps的常用判读方法讨论[J]. 岩土力学, 33(7): 2149-2159. doi: 10.3969/j.issn.1000-7598.2012.07.035 李华兵, 王喆, 许峰, 等, 2019. 四川盆地北缘米仓山隆起页岩气储层特征研究[J]. 非常规油气, 6(6): 1-6. doi: 10.3969/j.issn.2095-8471.2019.06.001 李玉飞, 付永强, 唐庚, 等, 2012. 地应力类型影响定向井井壁稳定的规律[J]. 天然气工业, 32(3): 78-80, 130-131. doi: 10.3787/j.issn.1000-0976.2012.03.018 刘合, 孟思炜, 苏健, 等, 2019. 对中国页岩气压裂工程技术发展和工程管理的思考与建议[J]. 天然气工业, 39(4): 1-7. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG201904002.htm 刘曰武, 高大鹏, 李奇, 等, 2019. 页岩气开采中的若干力学前沿问题[J]. 力学进展, 49(1): 201901. https://www.cnki.com.cn/Article/CJFDTOTAL-LXJZ201900001.htm 秦向辉, 陈群策, 赵星光, 等, 2020. 水压致裂地应力测量中系统柔度影响试验研究[J]. 岩石力学与工程学报, 39(6): 1189-1202. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202006010.htm 孙东生, 陈群策, 李阿伟, 2018-10-19. 一种水路转换开关及封隔器控制装置: 中国, 106761556B[P]. 孙东生, 庞飞, 李阿伟, 等, 2020. 基于流变模型的地应力剖面预测: 以贵州黔北地区安页1井为例[J]. 天然气工业, 40(3): 58-64. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG202003010.htm 田涛, 付德亮, 周世新, 等, 2020. 米仓山-汉南隆起区牛蹄塘组页岩古氧相及其与有机质富集的关系[J]. 兰州大学学报: 自然科学版, 56(1): 37-47, 55. https://www.cnki.com.cn/Article/CJFDTOTAL-LDZK202001005.htm 王宗起, 闫全人, 闫臻, 等, 2009. 秦岭造山带主要大地构造单元的新划分[J]. 地质学报, 83(11): 1527-1546. doi: 10.3321/j.issn:0001-5717.2009.11.001 危自根, 储日升, 杨小林, 等, 2019. 汉中盆地及邻区地壳结构和地震活动性研究[J]. 地震学报, 41(4): 445-458. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXB201904004.htm 谢富仁, 崔效锋, 赵建涛, 等, 2004. 中国大陆及邻区现代构造应力场分区[J]. 地球物理学报, 47(4): 654-662. doi: 10.3321/j.issn:0001-5733.2004.04.016 谢富仁, 崔效锋, 2015. 中国及邻区现代构造应力场图[Z]. 北京: 中国地图出版社. 谢和平, 高峰, 鞠杨, 等, 2016. 页岩气储层改造的体破裂理论与技术构想[J]. 科学通报, 61(1): 34-46. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB201601007.htm 许长春, 2012. 国内页岩气地质理论研究进展[J]. 特种油气藏, 19(1): 9-16. doi: 10.3969/j.issn.1006-6535.2012.01.002 薛浩, 高华新, 2013. 中国页岩气现状和未来简介[J]. 上海节能(9): 9-13. https://www.cnki.com.cn/Article/CJFDTOTAL-SHJL201309005.htm 杨树新, 姚瑞, 崔效锋, 等, 2012. 中国大陆与各活动地块、南北地震带实测应力特征分析[J]. 地球物理学报, 55(12): 4207-4217. doi: 10.6038/j.issn.0001-5733.2012.12.032 翟刚毅, 王玉芳, 刘国恒, 等, 2020. 鄂西地区震旦系—寒武系页岩气成藏模式[J]. 地质力学学报, 26(5): 696-713, doi: 10.12090/j.issn.1006-6616.2020.26.05.058. 张国伟, 郭安林, 董云鹏, 等, 2019. 关于秦岭造山带[J]. 地质力学学报, 25(5): 746-768. doi: 10.12090/j.issn.1006-6616.2019.25.05.064 张鹏, 孙治国, 王秋宁, 等, 2017. 木寨岭深埋隧道北段地应力测量与围岩稳定性分析[J]. 地质力学学报, 23(6): 893-903. https://journal.geomech.ac.cn/article/id/0febae11-4b7b-4e07-a1a7-24791d29026a 张欣, 2010. 南秦岭紫阳-镇巴地区基性侵入体动力学机制及地质意义讨论[D]. 西安: 长安大学. 张晓琪, 赵达成, 李章志贤, 等, 2021. 扬子陆块西北缘拉伸纪三期岩浆作用对Rodinia超大陆裂解的指示意义[J]. 西北大学学报(自然科学版), 51(6): 1042-1056. https://www.cnki.com.cn/Article/CJFDTOTAL-XBDZ202106011.htm 张文军, 秦绪乾, 郜瑭珺, 等, 2016. 米仓山隆起中新生代构造特征与形成演化探讨[J]. 天然气技术与经济, 10(2): 22-25, 33. doi: 10.3969/j.issn.2095-1132.2016.02.006 期刊类型引用(7)
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