International Journal of Rock Mechanics and Mining Sciences最新文献

{"title":"Influence of 3D forced water-based working fluid imbibition on dynamic responses of deep anisotropic shale reservoir","authors":"Yide Guo ,&nbsp;Linqi Huang ,&nbsp;Xibing Li","doi":"10.1016/j.ijrmms.2025.106195","DOIUrl":"10.1016/j.ijrmms.2025.106195","url":null,"abstract":"<div><div>Drilling and hydraulic fracturing are water-rich processes where shale reservoirs around wellbores and fractures often suffer forced water-based working fluid imbibition. In this study, we focus on increasing dynamic loads in deep shale gas extraction and report dynamic compression on thermally treated (25–200 °C) Longmaxi shale samples with five bedding orientations (0°, 30°, 45°, 60°, and 90°) after 3D forced water imbibition with four driving pressures (0, 3, 6, and 9 MPa). Results show that increasing water driving pressure increases the additional pore space inside shale samples non-linearly, and higher reservoir temperatures promote this effect. Increasing the water driving pressure obviously reduces dynamic compressive strengths of samples except those with the bedding orientation of 90° when the temperature exceeds 100 °C. Interestingly, approximate V-shaped curves between the dynamic strength and bedding orientation are neither affected by water driving pressure nor reservoir temperature. However, the anisotropy magnitude of dynamic strength is dependent on reservoir temperature and water driving pressure. Bedding activation for shale samples with bedding orientations of 30°, 45° and 60° is promising under high temperatures by increasing water driving pressure. Compared to pure thermal treatment, forced water imbibition limits the number of activated bedding planes in thermally treated shale samples with bedding orientations of 45° and 60°. Micro-mechanisms involving microstructural degradation, capillary force, poroelasticity, structural effective stress, dynamic viscous resistance, and dynamic fracture response explain the responses of strength magnitude, and the nature of stress wave propagation in bedded shale explains the responses of strength anisotropy. This study provides a basic understanding on dynamic responses of deep anisotropic shale reservoir considering reservoir temperature and forced water-based working fluid imbibition, which is applicable for improving drilling and hydraulic fracturing programs.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106195"},"PeriodicalIF":7.0,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic direct tensile behaviours of small-scale marble under sub-zero temperatures and high strain rate loading","authors":"Kai Liu ,&nbsp;Tingting Wang ,&nbsp;Gaofeng Zhao","doi":"10.1016/j.ijrmms.2025.106196","DOIUrl":"10.1016/j.ijrmms.2025.106196","url":null,"abstract":"<div><div>Understanding the dynamic tensile behaviour of frozen rock is essential for the design and stability of engineering structures in cold regions, where tensile cracking is the predominant failure mode in brittle rocks frequently subjected to dynamic disturbances and low temperatures. This paper presents a novel dynamic direct tension setup based on a dogbone-shaped rock specimen and a Hopkinson tensile bar system, which is integrated with a specialized environmental chamber and high-speed Digital Image Correlation (DIC). This setup enables precise investigation of rock tensile behaviour across a range of strain rates and temperatures, including sub-zero conditions. The method of characteristics is proposed to decouple the superimposed incident and reflected waves caused by the extended length of the striker bar. Pixel-based virtual extensometers from DIC confirm the validity of dynamic tensile tests by detecting misalignment or bending waves and capture the real-time cracking process as well as dynamic tensile strain with high precision. Dynamic direct tensile tests of small-scale specimen were performed at 20, -25, −55 and −70 °C using dry and saturated marble with a dogbone shape. The dynamic tensile strength of saturated marble increased from 6.10 MPa to 11.62 MPa, corresponding to an enhancement factor of 1.90. The results show significant temperature and rate dependencies in dynamic tensile strength, which increases as both ambient temperature decreases and strain rate increases. This behaviour is attributed to the transition of unfrozen water into ice, emphasizing the role of ice in filling pores and strengthening ice-rock interfaces. Intergranular microcracks are predominant during high-rate tensile testing at each low temperature. Furthermore, compared to dry marble, the fracture surface of saturated marble shows a number of transgranular cracks, resulting in the accumulation of debris. The findings hold valuable implications for blasting designs and dynamic disaster prevention in cold regions, such as high-altitude or deep space mining.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106196"},"PeriodicalIF":7.0,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of free surface width on blasting damage in open stope mining in narrow vein orebodies","authors":"Shian Zhang ,&nbsp;Xiuzhi Shi ,&nbsp;Xianyang Qiu ,&nbsp;Chengxing Zong ,&nbsp;Zhi Yu","doi":"10.1016/j.ijrmms.2025.106194","DOIUrl":"10.1016/j.ijrmms.2025.106194","url":null,"abstract":"<div><div>Underground narrow veins, typically less than 2–3 m thick but rich in precious metals, hold significant economic value. However, the confined free surface in the open stope poses substantial challenges for long-hole blasting, often leading to overbreak and underbreak, emphasising the need for optimising blasting parameters. To address this, understanding the influence of free surface width on blasting performance becomes critical. Therefore, a modified method based on the Scaled Heelan solution was employed to comprehensively investigate this influence, particularly its relationship with burden, velocity of detonation (VOD), and initiation positions. The indicators considered include blasting damage and fragment size distribution. The analysis allows the following conclusions: (1) both the damage volume and the fragment size are positively correlated with the width of the free surface within a certain range; (2) for a fixed free surface width, damage volume and fragment size increase with burden within an appropriate range, but an excessive burden prevents a blasting crater formation; (3) higher VOD does not always result in better fragmentation near the blasthole, and an optimal VOD lies approximately between the velocity of P- and S-wave; (4) the axial damage distribution depends on the initiation position but with minimal impact on radial damage. These findings provide a theoretical basis for burden and spacing design in narrow-vein open stoping and thereby contribute to improved blasting fragmentation efficiency.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106194"},"PeriodicalIF":7.0,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144510640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cryogenic strengthening effects on sandstone from 20 °C to −120 °C: Influence of initial water saturation and temperature","authors":"Guanglei Zhang ,&nbsp;Shiji Wang ,&nbsp;Wenze Song ,&nbsp;Yuliang Zhang ,&nbsp;P.G. Ranjith ,&nbsp;Guowei Ma","doi":"10.1016/j.ijrmms.2025.106183","DOIUrl":"10.1016/j.ijrmms.2025.106183","url":null,"abstract":"<div><div>The underground storage of liquefied natural gas (LNG) is an emerging concept aimed at large-scale natural gas storage. A comprehensive understanding of rock mechanics at ultra-low temperatures is essential for the safe and efficient design of such storage facilities. This study conducted uniaxial compression tests on sandstones at temperatures ranging from 20 °C to −120 °C to assess the effects of temperature and initial water saturation prior to freezing on their mechanical properties. Results indicate that sandstone strength increases progressively as temperatures decline under varying water saturation conditions. At −40 °C and −80 °C, the sandstone initially weakens at low water saturation levels but strengthens as saturation rises further. In contrast, at −120 °C, strength correlates positively with higher initial water saturation, with fully saturated samples exhibiting a 425 % strength enhancement compared to water-saturated sandstone tested at 20 °C. Micro-CT imaging indicates minimal changes in pore structure at −120 °C, suggesting negligible frozen damage to the sandstone. The significant strengthening observed at ultra-low temperatures can be attributed to three main factors: (1) the enhanced mechanical properties of rock minerals at low temperatures, as confirmed by <em>in-situ</em> nanoindentation; (2) increased ice strength with decreasing temperature, allowing ice to bear compressive loads; and (3) the prestress provided by ice expansion to surrounding rock minerals, placing them in a multiaxial stress state that significantly enhances strength. These results suggest that rock strength, particularly under water-saturated conditions, improves substantially at ultra-low temperatures, which is advantageous for underground LNG storage applications.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106183"},"PeriodicalIF":7.0,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of gas adsorption on coal relative permeability: a laboratory study","authors":"Tiancheng Zhang ,&nbsp;Jimmy Xuekai Li ,&nbsp;Yiran Zhu ,&nbsp;Victor Rudolph ,&nbsp;Zhongwei Chen","doi":"10.1016/j.ijrmms.2025.106191","DOIUrl":"10.1016/j.ijrmms.2025.106191","url":null,"abstract":"<div><div>CO₂ geo-sequestration and compressed air energy storage in depleted coal seam gas reservoirs are promising techniques for mitigating the greenhouse effect and combating climate change. However, gas adsorption-induced swelling in coal matrices poses challenges to gas injectivity by reducing both coal absolute permeability and relative permeability. While the sorption-induced impact on absolute permeability has been extensively studied, its impact on relative permeability remains little explored. To address this gap, a suite of two-phase flow experiments was conducted with both absorbing and non-absorbing gases. A series of relative permeability curves for helium-water, nitrogen-water, and CO₂-water systems were obtained. The results show lower relative permeability for absorbing gas-water systems (nitrogen and CO₂) compared to non-absorbing gas (helium) due to the sorption-induced swelling impact. Specifically, the relative permeability of helium-water systems is more than two times higher than that of nitrogen-water systems, followed by CO₂-water injection due to differences in adsorption capacity. Finally, quantitative correlations for estimating the relative permeability of nitrogen-water and CO₂-water systems were obtained, based on four newly introduced coefficients. These coefficients enable direct estimation of absorbing gas-water two-phase flow behavior (e.g., CO₂ sequestration and compressed air storage) in coal. The applicability of these coefficients was further validated using data from other studies, providing useful insights for assessing the injectivity of CO₂ geo-sequestration and underground compressed air energy storage.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106191"},"PeriodicalIF":7.0,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144481710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D stability and reliability of concave open pit slope in rock with Hoek-Brown strength criterion","authors":"Shilin Jia,&nbsp;Fei Zhang,&nbsp;Jian Ji,&nbsp;Zheming Zhang,&nbsp;Jie Xu","doi":"10.1016/j.ijrmms.2025.106190","DOIUrl":"10.1016/j.ijrmms.2025.106190","url":null,"abstract":"<div><div>The concave slope is a common feature in open pit mines. Due to the geometric effects, the concave slope can be designed with a steeper angle, which yields substantial economic benefits. However, two-dimensional (2D) analysis methods are unable to consider the additional stability provided by the three-dimensional (3D) effects. Furthermore, the inevitable uncertainties in the strength parameters of rocks severely compromise the slope stability. Therefore, reliance on the safety factor as a sole design acceptance criterion is inadequate and should be supplemented with failure probability. This paper aims to evaluate the 3D stability and reliability of concave open pit slopes. The slope instability in a geomaterial governed by the Hoek-Brown strength criterion is analyzed using a variationally derived 3D rotational failure mechanism. The stability analysis results are presented in dimensionless stability charts. Not surprisingly, the safety measures for slopes are greatly dependent on the Geological Strength Index and the slope geometric 3D effects. A closed-form solution for concave open pit slopes is proposed through regression analysis. It demonstrates high accuracy and can be employed to derive the limit state surface (LSS), which is adopted to conduct reliability analysis using First- and Second- Order Reliability Method (FORM and SORM). A series comparison is conducted to assess the performance of FORM and SORM. The findings reveal that FORM exhibits lower accuracy, whereas SORM maintains robust performance in comparison to the Monte Carlo simulation. Finally, the relationship between the mean safety factor and failure probability is established to guide the slope design of open pit mines.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106190"},"PeriodicalIF":7.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equivalent gas aperture of rock fracture: Theoretical model and experimental validation","authors":"Yaoyao Zhao,&nbsp;Zhihong Zhao,&nbsp;Yunzhe Jin","doi":"10.1016/j.ijrmms.2025.106186","DOIUrl":"10.1016/j.ijrmms.2025.106186","url":null,"abstract":"<div><div>Fractures are the main channels for fluid and gas flow in rock masses. Hydraulic aperture, which is derived for an incompressible fluid, is commonly employed to characterize flow properties of rock fractures. However, hydraulic aperture may not be suitable for describing the gas flow behavior through rock fracture when considering gas compressibility and slippage. Therefore, a new concept of gas aperture is proposed to characterize gas flow properties of rock fractures, and its definition and determination procedure are provided. A number of gas flow tests on granite fractures with flat or rough surfaces are conducted under varying confining and gas pressures. The results show that hydraulic apertures can underestimate gas apertures by 5–30 % when the ratio of the gas pressure difference between inlet and outlet to the mean gas pressure exceeds 0.25. Finally, an empirical formula is developed to describe the relationship between mechanical and gas apertures. This study advances understanding of gas flow behavior in rock fractures through the novel gas aperture concept, overcoming the limitations of hydraulic aperture in gas flow scenarios and enabling enhanced predictive modeling of gas transport in fractured rock masses.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"194 ","pages":"Article 106186"},"PeriodicalIF":7.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anisotropic dynamic-static elasticity correlations in lacustrine shales: Experimental insights for in situ stress estimation","authors":"Yang Wang ,&nbsp;Luanxiao Zhao ,&nbsp;Dingdian Yan ,&nbsp;Lingwei Ma ,&nbsp;Zhenjia Cai ,&nbsp;Bohua Zhu ,&nbsp;De-hua Han","doi":"10.1016/j.ijrmms.2025.106182","DOIUrl":"10.1016/j.ijrmms.2025.106182","url":null,"abstract":"<div><div>Dynamic-static elasticity correlation is of great concern in numerous geo-engineering applications, like <em>in situ</em> stress prediction. However, establishing a precise dynamic-static correlation in unconventional shales is challenging due to their intrinsic anisotropy and the <em>in situ</em> stress field anisotropy. We perform multi-stage deviatoric stress cycling tests together with ultrasonic velocity measurements on 13 pairs of lacustrine shales, intending to establish the anisotropic dynamic-static elasticity correlations considering the <em>in situ</em> horizontal stress. The experimental results reveal that dynamic Young's moduli are greater than their static counterparts, while there are no unified relations for dynamic-static Poisson's ratios. From a microscopic view, the dynamic-static contrasts are attributed to friction-slip-related events across bedding/grain contacts and crack interfaces induced by a stress increment. The bedding-normal dynamic-static Young's modulus correlation is directly established using the measured data at 21 MPa confining pressure, equivalent to the <em>in situ</em> horizontal stress. Additionally, there exists a linear relationship between dynamic and static Young's modulus anisotropy (<em>E</em>₁₁/<em>E</em>₃₃). Hence, the bedding-parallel static Young's modulus is indirectly deduced by combining the bedding-normal dynamic-static correlation with the dynamic-static anisotropy linear relationship. Ultimately, the anisotropic dynamic-static correlations are applied to calculate the stress coupling factor, a key parameter in stress profile prediction. After comparing with the stress coupling factor derived without dynamic-static conversions in well logging, we get an implication that neglecting anisotropic dynamic-static correlations would significantly underestimate <em>in situ</em> horizontal stresses in shale reservoirs.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"193 ","pages":"Article 106182"},"PeriodicalIF":7.0,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transmission of ultrasonic wave across moisture rocks: Effects of moisture sorption on velocity variation and attenuation","authors":"Ang Liu ,&nbsp;Guijie Sang ,&nbsp;Shimin Liu ,&nbsp;Xing Li ,&nbsp;Gang Wang","doi":"10.1016/j.ijrmms.2025.106188","DOIUrl":"10.1016/j.ijrmms.2025.106188","url":null,"abstract":"<div><div>This study focused on investigating the impact of moisture-induced mechanical degradation on three types of rocks. Dynamic moisture sorption experiments were conducted to understand water vapor sorption across different relative humidity (RH) conditions. Ultrasonic tests, performed at various RH levels, revealed the sensitivity of wave velocities and attenuations to changes in moisture content. Subsequent measurements of unconfined compressive strength (UCS) demonstrated how moisture-induced degradation affects the mechanical properties of rocks. This study evaluated the effects of RH on ultrasonic P-/S-wave velocities in three rocks, revealing distinct moisture effects on wave velocity variations. Gray shale and sandstone exhibited similar P-wave behaviors, while black shale differed significantly, showcasing early stiffening effects at lower RH. Saturation heterogeneities at the pore-scale and patchy effects at the large scale highlighted complex interactions between rock, moisture, and wave characteristics. Furthermore, the research assessed the impact of relative humidity on ultrasonic wave attenuations in partially saturated rocks. As RH increased, P-wave attenuation generally rose, influenced by dynamic water saturation and fabric heterogeneity. S-wave attenuation exhibited a similar trend, with noticeable variations among rock types. UCS tests indicated that higher moisture content led to decreased UCS values across various rock specimens. The P- and S-wave velocities during loading further emphasized moisture sensitivity, with S-wave velocity being more responsive to moisture content variations. Dynamic Young's moduli exhibited distinct changes during UCS measurements, highlighting the influence of moisture content on mechanical degradations. These findings underscore the importance of considering moisture effects in understanding and predicting the mechanical behavior of rocks.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"193 ","pages":"Article 106188"},"PeriodicalIF":7.0,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling supercritical CO2 injection induced rupture of a minor fault embedded in a poroelastic layered reservoir-caprock system","authors":"Meng Cao,&nbsp;Jonny Rutqvist,&nbsp;Yves Guglielmi,&nbsp;Abdullah Cihan,&nbsp;Stanislav Glubokovskikh,&nbsp;Preston Jordan,&nbsp;Matthew Reagan,&nbsp;Jens Birkholzer","doi":"10.1016/j.ijrmms.2025.106185","DOIUrl":"10.1016/j.ijrmms.2025.106185","url":null,"abstract":"<div><div>CO₂ injection for geologic carbon sequestration involves hydromechanical processes that lead to changes in fluid pressure and stresses that can activate existing faults. This paper presents a new method and workflow of modeling fault activation considering more complex three-dimensional geometry of natural faults using the TOUGH-FLAC multiphase fluid flow and geomechanical simulator. In this method and workflow, FLAC3D mechanical interfaces and TOUGH3 finite volume elements are discretized using computer aided design and gridding software along with a tailored mesh translation routine. The method and workflow are demonstrated with a model of a curved minor fault embedded in a poro-elastic layered reservoir-caprock system. The model is used for a comprehensive sensitivity analysis of fault responses to fault length, injection mass rate, injection schedule, well-fault distance, and well locations versus fault location. Four metrics (CO₂ plume, shear state of fault, pressure and stress path at fault monitoring points) are selected to assess CO₂ migration, pressure change, and the reactivation of faults. The results reveal that CO₂ can bypass around the tip of the minor impermeable fault, building up pressure and poro-elastic stress on both sides that tends to impede fault rupture. Our study shows the benefit of carefully designing the injection to achieve the targeted final storage volume, starting at a relatively low rate for considerable time, and then ramping up the injection rate to the full rate of injection. The initial low injection has two distinct benefits: (1) it allows for the formation of an extensive CO₂ plume with a much higher mobility through a low viscosity that will result in a lower pressure for a given injection rate, and (2) it allows for gradual build-up of horizontal poro-elastic stress within the reservoir that will tend to impede activation of steeply dipping faults. The injection scenario starting at a low injection rate, denoted here as conservative injection, can significantly reduce the risk of fault activation as high fluid mobility and reservoir strengthening poro-elastic stress has been established long before reaching the peak injection rates. Moreover, simultaneous injection in two injection wells on both sides of fault can provide further reservoir strengthening through poro-elastic stress buildup acting on a fault under normal faulting stress regime. The findings presented in the paper can provide practical and effective guidance on long-term, safe, and reliable geological CO₂ storage.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"193 ","pages":"Article 106185"},"PeriodicalIF":7.0,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}