1.中山大学地球科学与工程学院,广东 珠海 519082
2.广东省地球动力作用与地质灾害重点实验室,广东 珠海 519082
3.南方海洋科学与工程广东省实验室(珠海),广东 珠海 519082
马泽强(1999年生),男;研究方向:断层泥摩擦;E-mail:mazq7@mail2.sysu.edu.cn
刘金锋(1985年生),男;研究方向:高温高压岩石力学;E-mail:liujinf5@mail.sysu.edu.cn
纸质出版日期:2024-09-25,
网络出版日期:2024-07-02,
收稿日期:2024-04-01,
录用日期:2024-04-26
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马泽强,刘金锋,范财源.水岩反应蚀变矿物对模拟花岗岩断层泥摩擦系数与速度依赖性的影响[J].中山大学学报(自然科学版)(中英文),2024,63(05):13-27.
MA Zeqiang,LIU Jinfeng,FAN Caiyuan.Effect of water-rock reaction altered minerals on friction coefficient and velocity dependence of simulated granite fault gouges[J].Acta Scientiarum Naturalium Universitatis Sunyatseni,2024,63(05):13-27.
马泽强,刘金锋,范财源.水岩反应蚀变矿物对模拟花岗岩断层泥摩擦系数与速度依赖性的影响[J].中山大学学报(自然科学版)(中英文),2024,63(05):13-27. DOI: 10.13471/j.cnki.acta.snus.ZR20240094.
MA Zeqiang,LIU Jinfeng,FAN Caiyuan.Effect of water-rock reaction altered minerals on friction coefficient and velocity dependence of simulated granite fault gouges[J].Acta Scientiarum Naturalium Universitatis Sunyatseni,2024,63(05):13-27. DOI: 10.13471/j.cnki.acta.snus.ZR20240094.
地热开采过程中水岩反应生成的蚀变矿物可能会影响储层断层的摩擦特性,进而诱发不稳定滑动。本文以深圳东北部潜在地热储层的断裂构造为背景,考虑了埋深约2.5 km、温度约150 ℃的储层条件及横岗-罗湖断裂带,估算得出流体注入导致断层滑动的临界孔隙流体压力(约50 MPa)及临界有效正应力(约20 MPa)。热力学计算表明,在临界流体压力及地热温度下,高产热燕山期花岗岩粉末与水反应在平衡状态下生成的蚀变矿物为:二氧化硅、高岭石和绿泥石,质量比为16∶7∶2。基于此,本文在室温、恒定含水率(10%)及恒定有效正应力(20 MPa)条件下,通过19个速度阶跃直剪试验,研究了3种蚀变矿物单独作用及其共同作用下对模拟花岗岩断层泥的摩擦系数及其速度依赖性的影响,并结合声发射及微观特征分析了其控制机理。试验结果表明:天然花岗岩粉末的摩擦系数为0.64,表现为速度弱化。单种蚀变矿物作用下,二氧化硅对模拟花岗岩断层泥的摩擦系数影响不显著,但能增强断层泥速度弱化特性,甚至引发黏滑;相反,黏土矿物(高岭石和绿泥石)可以显著降低断层泥的摩擦系数,并起速度强化的作用。3种蚀变矿物共同作用下,黏土矿物起主控作用:降低断层泥的摩擦系数,并起速度强化的作用。微观结构分析发现,相比于3种蚀变矿物总含量为33%的变形样品,总含量为67%的变形样品未观察到明显的剪切带且累计声发射事件数显著下降,暗示其变形可能从脆性转变为半塑性。如果在深圳东北部地热储层进行地热开采,应当控制流体注入压力避免断层滑动。
Altered minerals introduced by water-rock reactions during geothermal energy recovery may play a role in the frictional properties of fault gouges, perhaps inducing earthquakes. Based on the geological conditions of potential geothermal reservoirs in northeastern Shenzhen, this paper considers the critical pore pressure (about 50 MPa) and critical effective normal stress (about 20 MPa), which may lead to reactivation of the Henggang-Luohu fault zone due to fluid injection into a potential geothermal reservoir at a buried depth of about 2.5 km with the temperature of 150 ℃. Under such hydrothermal conditions (50 MPa fluid pressure and 150 ℃), thermodynamic calculations suggest that the reaction of Yanshanian granular granite and water, at equilibrium, can produce silica, kaolinite, and chlorite at a mass ratio of 16∶7∶2. Here we report 19 direct shear experiments performed on simulated fault gouges consisting of the binary mixture of silica + granite, kaolinite + granite, and chlorite + granite, and the multivariate mixture of silica + kaolinite + chlorite + granite, to investigate the effects of altered minerals on frictional properties of simulated granite fault gouges. Velocity stepping experiments were conducted on the wet samples with 10% water content at an initial normal stress of 20 MPa under drained conditions at room temperature. On this basis and together with acoustic emission observation and microstructural analysis, we discussed the likely mechanism responsible for the observed behavior. The results show that, for the presence of a single altered mineral, silica has little effect on the friction coefficient, though it contributes to velocity weakening and even stick-slip events. Whereas, clay minerals can significantly decrease the friction coefficient, though they have a contribution to velocity strengthening. For the presence of a mixture of silica + kaolinite + chlorite, clay minerals play a dominant role in controlling frictional properties of the simulated fault gouges: altered minerals can also significantly decrease the friction coefficient and contribute to velocity strengthening. Development of R1 shear planes was observed using microstructural analysis for the simulated granite fault gouges consisting of 0% or 33% of the altered minerals, while the R1 shear plane cannot be observed anymore in the sample consisting of 67% of the altered minerals. The number of acoustic emission events decreases significantly when the content of the altered minerals is 33%~67%. This may indicate a transition in the deformation mechanism from brittle to semi-plastic. Our study suggests that if geothermal energy recovery is carried out in northeastern Shenzhen, the fluid injection pressure should be controlled to avoid the slip of the fault.
地热开采摩擦特性水岩反应蚀变矿物
geothermal miningfriction characteristicswater-rock reactionalteration minerals
路珍,2014. 含黑云母断层岩碎屑在热水条件下的摩擦滑动实验研究——含弱矿物断层的力学性质研究[D]. 北京: 中国地震局地质研究所.
李彬,2022. 地热田干热岩地应力测量及其特征研究——以广东惠州地热田为例[D]. 西宁: 青海大学.
刘贺娟,童荣琛,侯正猛,等,2022. 地下流体注采诱发地震综述及对深部高温岩体地热开发的影响[J]. 工程科学与技术,54(1): 83-96.
谢和平,杨仲康,邓建辉,2019. 粤港澳大湾区地热资源潜力评估[J]. 工程科学与技术,51(1): 1-8.
余成华,2010. 深圳断层活动性和地震危险性研究[D]. 杭州: 浙江大学.
曾凡蛟,2013. 横岗—罗湖断裂特征及第四纪活动性[J]. 科技资讯,11(4): 160-162.
张雷,何昌荣,周永胜,2020. 水热条件下富层状硅酸盐矿物糜棱岩的摩擦特性实验研究[J]. 地球物理学报,63(2): 573-582.
ALT-EPPING P,DIAMOND L W,HÄRING M O,et al,2013. Prediction of water-rock interaction and porosity evolution in a granitoid-hosted enhanced geothermal system,using constraints from the 5 km Basel-1 well[J]. Appl Geochem,38: 121-133.
AN M,ZHANG F,MIN K B,et al,2021. The potential for low-grade metamorphism to facilitate fault instability in a geothermal reservoir[J]. Geophys Res Lett,48(11): e2021GL093552.
AN M,ZHANG F,MIN K B,et al,2022. Frictional stability of metamorphic epidote in granitoid faults under hydrothermal conditions and implications for injection-induced seismicity[J]. J Geophys Res Solid Earth,127(3): e2021JB023136.
ASHMAN I R,FAULKNER D R,2023. The effect of clay content on the dilatancy and frictional properties of fault gouge[J]. J Geophys Res Solid Earth,128(4): e2022JB025878.
BELZER B D,FRENCH M E,2022. Frictional constitutive behavior of chlorite at low shearing rates and hydrothermal conditions[J]. Tectonophysics,837: 229435.
BLANPIED M L,LOCKNER D A,BYERLEE J D,1991. Fault stability inferred from granite sliding experiments at hydrothermal conditions[J]. Geophys Res Lett,18(4): 609-612.
BLANPIED M L,LOCKNER D A,BYERLEE J D,1995. Frictional slip of granite at hydrothermal conditions[J]. J Geophys Res Solid Earth,100(B7): 13045-13064.
CHEN J,SPIERS C J,2016. Rate and state frictional and healing behavior of carbonate fault gouge explained using microphysical model[J]. J Geophys Res Solid Earth,121(12): 8642-8665.
CHEN J,van den ENDE M P A,NIEMEIJER A R,2020. Microphysical model predictions of fault restrengthening under room-humidity and hydrothermal conditions: From logarithmic to power-law healing[J]. J Geophys Res Solid Earth,125(4): e2019JB018567.
DIETERICH J H,1978. Time-dependent friction and the mechanics of stick-slip[J]. Pure Appl Geophys,116(4): 790-806.
DIETERICH J H,1979. Modeling of rock friction: 1. Experimental results and constitutive equations[J]. J Geophys Res Solid Earth,84(B5): 2161-2168.
JAEGER J G,COOK N G W,ZIMMERMAN R W,2007. Fundamental of rock mechanics[M].
LOGAN J M,1979. Experimental studies of simulated gouge and their application to studies of natural fault gouge[J]. Analysis of Actual Fault Zones in Bedrock,305-343.
MAIR K,MARONE C,YOUNG R P,2007. Rate dependence of acoustic emissions generated during shear of simulated fault gouge[J]. Bull Seismol Soc Am,97(6): 1841-1849.
MOORE D E,LOCKNER D A,2011. Frictional strengths of talc-serpentine and talc-quartz mixtures[J]. J Geophys Res Solid Earth,116(B1): B01403.
OKAMOTO A S,VERBERNE B A,NIEMEIJER A R,et al,2019. Frictional properties of simulated chlorite gouge at hydrothermal conditions: Implications for subduction megathrusts[J]. J Geophys Res Solid Earth,124(5): 4545-4565.
ROWE C D,LAMOTHE K,REMPE M,et al,2019. Earthquake lubrication and healing explained by amorphous nanosilica[J]. Nat Commun,10(1): 320.
RUINA A,1983. Slip instability and state variable friction laws[J]. J Geophys Res Solid Earth,88(B12): 10359-10370.
TAKAHASHI M,MIZOGUCHI K,KITAMURA K,et al,2007. Effects of clay content on the frictional strength and fluid transport property of faults[J]. J Geophys Res Solid Earth,112(B8): B08206.
TEMBE S,LOCKNER D A,WONG T F,2010. Effect of clay content and mineralogy on frictional sliding behavior of simulated gouges: Binary and ternary mixtures of quartz,illite,and montmorillonite[J]. J Geophys Res Solid Earth,115(B3): B03416.
TOY V G,NIEMEIJER A,RENARD F,et al,2017. Striation and slickenline development on quartz fault surfaces at crustal conditions: Origin and effect on friction[J]. J Geophys Res Solid Earth,122(5): 3497-3512.
WESTAWAY R,BURNSIDE N M,2019. Fault “corrosion” by fluid injection: A potential cause of the November 2017 MW 5.5 Korean earthquake[J]. Geofluids,2019: 1280721.
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