Geofluids最新文献

{"title":"A Novel Model for Forecasting Production Performance in Waterflood Oil Reservoirs","authors":"Yajun Gao,&nbsp;Yang Liu,&nbsp;Xiaoqing Xie,&nbsp;Lihui Tang,&nbsp;Yuqian Diao,&nbsp;Yuhua Ma","doi":"10.1155/2024/4584237","DOIUrl":"https://doi.org/10.1155/2024/4584237","url":null,"abstract":"<p>The importance of production performance forecasting in reservoir development and economic evaluation cannot be overstated. Previous models have shown deficiencies in accurately predicting production performance, necessitating the development of a new semianalytical model to enhance its application scope and prediction accuracy. This study proposes a novel semianalytical model based on the Buckley–Leverett (BL) equation and a newly proposed linear relationship between outlet water saturation and average water saturation, as well as Willhite’s formula of oil/water relative permeability. The results demonstrate the universality of this new model, as it can generate three equivalent log-linear relations, including the previously proposed model. Sensitivity analysis confirms the applicability of the model in various reservoirs. In addition, both model and field case studies highlight the advantages of this technique in forecasting water cut and cumulative oil production, with an extensive application scope covering over 90% of the water cut range. A comparison of oil production prediction results from six different predictive methods reveals that the proposed semianalytical model exhibits the lowest error rate of −0.01%. Moreover, the semianalytical model can be utilized to directly solve for the approximate values of the exponents in Willhite’s oil/water relative permeability equations. In summary, this novel semianalytical forecasting model demonstrates a robust ability to forecast water cut, cumulative oil production, and recovery efficiency.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/4584237","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation Between Chang-9 Crude Oil and Potential Source Rocks, Upper Triassic Yan-Chang Formation, Middle Area of Ordos Basin: Correlation Between Crude Oil in the Chang-9 Member and Potential Source Rocks","authors":"Yan Liu,&nbsp;Han Yue,&nbsp;Rongxi Li,&nbsp;Xuefeng Liu","doi":"10.1155/2024/4861384","DOIUrl":"https://doi.org/10.1155/2024/4861384","url":null,"abstract":"<p>The Chang 9 oil layer deposits within Ansai District, Ordos Basin, yield considerable reserves of crude oil, yet their source remains ambiguous. This research endeavor was designed to characterize the Chang 9 crude oil and the Chang 7 and Chang 9 source rocks (SRs) of the Yan-Chang Formation via organic geochemical analysis. The results indicate that the Chang 9 crude oil exhibits a Pr/Ph ratio of 0.84–2.29 and Ga/C₃₀H less than 0.1, implying formed in a weak reduction to weak oxidation freshwater environment. The regular sterane C₂₇-C₂₈-C₂₉ configuration assumes an inversed “L” type, reflecting mixed sources and dominant terrestrial plant input. Ratios such as C₂₉20<i>S</i>/(20<i>S</i> + 20<i>R</i>) (0.54–0.6) and C₂₉<i>β</i><i>β</i>/(<i>β</i><i>β</i> + <i>α</i><i>α</i>) (0.44–0.58) indicate a mature oil stage. The depositional environment of the C7 and C9 SRs is similar, with weak oxidation to reduction conditions, and consists mainly of Type I and II organics, with a relatively higher maturity of the C9 SRs. A difference in C₁₉/C₂₃TT and C₃₀D/C₃₀H was found between the C7 and C9 SRs. The results show that the C9 crude oils have a similar C₁₉/C₂₃TT with the C9 SRs and similar diahopanes distribution with Class II SRs (C7 and part of the C9 SRs). Thus, the C9 crude oils most likely originate from the C9 SR mixed with the C7 SRs.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/4861384","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142316753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Precise Analysis of the Behavior of Pit Side Tunnels Caused by Deep Excavation","authors":"Huasheng Sun,&nbsp;Yuexin Zhao,&nbsp;Yadong Chen,&nbsp;Jiahui Li","doi":"10.1155/2024/5573986","DOIUrl":"https://doi.org/10.1155/2024/5573986","url":null,"abstract":"<p>As urbanization gathers pace, projects involving adjacent subway tunnels are increasing, thereby amplifying the need for robust tunnel protection measures. Currently, there exists a notable lack of precise analyses on the three-dimensional (3D) deformation laws and mechanisms of tunnels affected by adjacent deep excavation. Moreover, the influence patterns of retaining wall stiffness and deep excavation depth on the 3D deformation of pit-side tunnels remain unclear. The purpose of this research is to bridge the existing disparity by adopting the hypoplastic model, which effectively captures soil stiffness that is dependent on soil state, strain, and stress path, even at small strains, as well as soil strength, based on reported centrifuge model tests. This approach facilitates a comprehensive, precise numerical analysis of the interaction between deep excavation and preexisting tunnels located outside the retaining wall. The analysis sheds light on the deformation mechanisms and trends of pit-side tunnels not solely confined to the longitudinal axis but extending to the transverse plane as well, while systematically examining the influence of varying excavation depths and retaining wall stiffness on key tunnel parameters, including longitudinal deformation, diameter changes, bending strains, and soil pressure distributions around the tunnels. The study reveals that if the tunnel situated outside the retaining structure lies beneath the foundation pit’s base, deep excavation only slightly deforms the tunnel. However, when the tunnel outside the retaining structure is positioned above the pit’s base, its deformation progressively intensifies with deeper excavation, but the growth rate has a decreasing trend. An enhancement in the stiffness of the retaining wall results in a notable decrease in the deformation exhibited by the adjacent tunnels. The findings contribute to a deeper understanding of the complex responses of pit-side tunnels to excavation activities, ultimately facilitating the design and construction of safer and more resilient urban subway infrastructure.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/5573986","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142313257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Chemical Properties and Formation Mechanisms of Shallow Groundwater in the Guohe River Basin, China","authors":"Qing Zhang,&nbsp;Liang Li,&nbsp;Weiya Ge,&nbsp;Yunfeng Li,&nbsp;Zongfang Chen,&nbsp;Jian Hua,&nbsp;Yuanzhi Lu,&nbsp;Jingjing Du","doi":"10.1155/2024/3283185","DOIUrl":"https://doi.org/10.1155/2024/3283185","url":null,"abstract":"<p>An investigation of the distribution and control factors of groundwater is significant for the rational exploitation and utilization of groundwater resources. This study analyzes the hydrogeochemical processes and control factors of shallow groundwater in the Guohe River Basin. A hydrogeological survey was conducted, and hydrochemical and hydrogen–oxygen isotopic data of 125 samples of surface water and groundwater were analyzed. The results showed that the total dissolved solid (TDS) content in shallow groundwater was 138–2967 mg/L, with an average of 831 mg/L. A decline in the TDS was observed from the upper to the lower reaches. The contents of the anions and cations in the shallow groundwater were in the order HCO₃⁻ &gt; Cl⁻ &gt; SO₄²⁻ and Na⁺ and K⁺ &gt; Mg²⁺ &gt; Ca²⁺, respectively. The cation exchange increased the aqueous concentrations of Na⁺ and K⁺, and the TDS content was highly correlated with the contents of Na⁺, Cl⁻, and SO₄²⁻ ions. The <i>δ</i>D and <i>δ</i>¹⁸O values in shallow groundwater increased from the upper to the lower reaches, with the mean <i>δ</i>D values being −59.72‰, −53.58‰, and −47.17‰ and the mean <i>δ</i>¹⁸O values being −8.33‰, −7.37‰, and −6.43‰. The contribution rates of the recharge source, evaporation, and water–rock interaction to the groundwater TDS concentration were 20.4%, 29.5%, and 50.1%, respectively. The water–rock interaction dominated the formation of shallow groundwater in the Guohe River Basin. The dissolution of salt rock and gypsum contributed to ion formation in shallow groundwater. The research findings can be used to improve the groundwater quality in the Guohe River Basin.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/3283185","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142273034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining Deterministic and Probabilistic Approaches in an Improved Volumetric Model With the Aim to Reduce Geological Uncertainties for Accurate Hydrocarbon Reserve Estimation: Case Study in the Rio Del Rey Basin, Cameroon","authors":"Bawane Godwe Justine,&nbsp;Mambou Ngueyep Luc Leroy,&nbsp;Tchotang Theodore,&nbsp;Eze Eze Jordan","doi":"10.1155/2024/3020626","DOIUrl":"https://doi.org/10.1155/2024/3020626","url":null,"abstract":"<p>The aim of this study is to improve hydrocarbon reservoir estimation by combining the deterministic and probabilistic approaches in an improved volumetric model with the objective of reducing geological uncertainties and achieving better reserve estimations. The case study was made in the Rio Del Rey basin of Cameroon. To achieve this goal, a mathematical model was built using the volumetric expression of the stock tank original oil in place (STOIIP), the Raymer–Hunt expression of porosity and transit time, and the Simandoux model modified by the Schlumberger expression of water saturation. The application and validation of the proposed model were made through Interactive Petrophysics, Petrel software, and Monte Carlo simulation on Minitab Workspace. The results obtained by a deterministic approach on the investigated area of 2000 m² give a total estimated quantity of oil in place of 11897.67 MMbbl, a total estimated quantity of gas in place of 27.79 Bcf, a total estimated quantity of recoverable oil of 3606.28 MMbbl, and a total estimated quantity of recoverable gas of 19.52 Bcf. The probabilistic approach permitted to obtain an estimated quantity of oil in place of 150194141.45 MMbbl. In this study, it appears that the net value added is $288,898,222. This therefore confirms the accuracy of the model and the profitability of the project.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/3020626","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Law Regarding Damage Caused by Repeated Mining in Close Coal Seams","authors":"Fuzhu Wu,&nbsp;Gen Chen,&nbsp;Yanjie Liu,&nbsp;Yonghui Wu,&nbsp;Zidong Jin","doi":"10.1155/2024/1576488","DOIUrl":"https://doi.org/10.1155/2024/1576488","url":null,"abstract":"<p>Coal mining in China is increasingly moving towards deeper resources. In certain Carboniferous–Permian coal fields in North China, there is a typical problem of repeated mining over short distances and multiple coal seams, and the distance between the main coal seam and the mined shallow coal seam is relatively small. This leads to repetitive disturbance damage to the surrounding rock during closed-coal seam mining. This was followed by more serious threats from water disasters. Therefore, it is particularly important to systematically study the disturbance and failure characteristics of rock masses under repeated mining conditions in multiple coal seams and to investigate repeated mining damage law and characteristics of the overlying rock of a close coal seam. This study focuses on six mining areas in the Jiyang coal mine. This study also predicts the damage height of the top and bottom slabs of mined No. 7 coal and main mined No. 10 coal based on an empirical formula. An on-site investigation was conducted using downhole drilling and segmental water injection to determine the damage depths of the two seams. A numerical simulation was then conducted to study the height, displacement, and stress of the overlying rock damage caused by mining close to the coal seams. Changes in height, displacement, and stress of the overburden rock mining damage were also studied through numerical simulations. Results indicated the following: (1) The height of the plastic zone of the overburden rock increased by 6.25%, (2) maximum settlement displacement increased by 5.05%, and maximum horizontal displacement increased by 9%. It is important to note that these findings are objective and based solely on presented data. Repetitive disturbances with larger amplitudes caused a 27% change in horizontal displacement. (3) Maximum principal stress in the stress field decreased with the overall value of the vertical stress. The influence range increased slightly and the two sides of the hollow area at the open cutting eye and stopping line were also affected. These findings were obtained through numerical simulations. Stress concentration was more pronounced in the open-cut eye and near-the-stop line.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/1576488","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biot Theory Yields a Specific Storage Coefficient With Natural Deformation of Rock","authors":"Guangquan Li,&nbsp;Simeng Yang,&nbsp;Li Wang","doi":"10.1155/2024/4391320","DOIUrl":"https://doi.org/10.1155/2024/4391320","url":null,"abstract":"<p>The traditional specific storage coefficient (<i>S</i>_<i>s</i>) was defined under two assumptions. One is that aquifer rock deforms only in the vertical direction, and the other is that the average rock stress remains unchanged. Consequently, <i>S</i>_<i>s</i> is irrelevant to the shear modulus of rock (<i>G</i>). In this paper, the Biot theory is used to derive a new specific storage coefficient (<span></span><math></math>) with the natural deformation of rock. <span></span><math></math> appears to be relevant to <i>G</i>. Compressed glass beads and Berea sandstone are used for illustration. At frequencies lower than 10 kHz, the equation of groundwater flow with <span></span><math></math> yields the same phase velocity and quality factor as the Biot theory, and therefore, it is capable of accurately predicting fluid pressure diffusion in the low-frequency regime. The results also show that <i>S</i>_<i>s</i> is 16%–17% higher than <span></span><math></math>. In conclusion, the latter one is superior to the former in its consistency with the Biot theory and unconstraint by the aforementioned two assumptions.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/4391320","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Feldspar Dissolution on the Pore Structure and Characteristics of a Tight Sandstone Reservoir: A Case Study From the Northeast Margin of Ordos Basin, China","authors":"Yanhe Zhu,&nbsp;Zhigang Zhao,&nbsp;Xin Li,&nbsp;Chang Liu,&nbsp;Shanshan Yu,&nbsp;Yuanyuan Lu,&nbsp;Xuejia Du","doi":"10.1155/2024/9069384","DOIUrl":"https://doi.org/10.1155/2024/9069384","url":null,"abstract":"<p>The Ordos Basin is the main tight gas-producing basin in China. Under the background of strong heterogeneous physical property, there is still high porosity and permeability “sweet spot” in tight reservoirs. Feldspar dissolution exerts a significant effect on porosity/permeability, while its genetic mechanism is unclear, which restricts the prediction of effective reservoir. In this paper, genesis of feldspar dissolution and its effect on reservoir heterogeneity were studies. Carboniferous-Permian Formation, which is the main gas-producing strata in northeast margin of Ordos Basin, is taken as the target. Based on the methods of thin section observation, physical property test, inclusion, isotope and productivity analysis, mechanism of feldspar dissolution, and its positive modification to tight sandstone reservoir are studied. The results show that the target sandstone is dominantly made up of litharenite and feldspathic litharenite. About 98.6% of the samples possess permeability less than 1 mD, while 89.7% of the samples possess porosity less than 10%. The high porosity/permeability space within tight reservoirs is dominated by dissolved pores, accounting for more than 80% of the total pore space. The dissolution minerals are mainly associated with feldspar, and the amount of feldspar dissolution is positively correlated with porosity and permeability. According to the fluid chemical information of quartz overgrowth and ankerite (related to feldspar dissolution), feldspar dissolved pores are caused by organic acid derived from the thermal maturity of organic matter. According to production data, no daily production can be achieved in single well, when the porosity and permeability are less than 7% and 0.1 mD, respectively. However, once it exceeds this porosity/permeability threshold value, the production capacity is exponentially improved. Furthermore, when surface porosity of feldspar dissolution exceeds 7%, most values of the porosity and permeability exceed the threshold values of the allowable productivity, indicating that extensive feldspar dissolution is favorable factor for effective reservoir space development in tight reservoirs.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/9069384","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142123137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Key Bearing Structure Instability Mechanism: A Case Study in Mining Under Close-Distance Coal Pillar","authors":"Jieyang Ma,&nbsp;Shihao Tu,&nbsp;Hongsheng Tu,&nbsp;Kaijun Miao,&nbsp;Hongbin Zhao,&nbsp;Long Tang","doi":"10.1155/2024/1321869","DOIUrl":"https://doi.org/10.1155/2024/1321869","url":null,"abstract":"<p>This study is aimed at solving the issue of mining under the boundary coal pillar of the close-distance coal seam that causes roof falling. This study established a new key bearing structure model for analyzing the structural instability mechanism when mining under the coal pillar at the working face by taking Shaping Coal Mine as an example. The purpose of this study is to analyze the formation process, load transfer mechanism, and two failure types of the key bearing structure using theoretical analysis and numerical simulation. Additionally, this study discussed the timing and method of roof control for different key bearing structure failure types. Research shows that the instability of the key bearing structure composed of the coal pillar, interlayer rock, and lower coal body is the important reason behind the roof falling. The instability types of key bearing structures include the coal pillar instability type and the cantilever beam instability type. The stability width of the interlayer rock cantilever beam and the coal pillar jointly ascertain the failure type of the key bearing structure. In the 9204 working face, the key bearing structure was destroyed when the coal pillar was 14 m wide, resulting in the roof stress being as high as 31.81 MPa. The stress drop phenomenon can be used as a boundary to divide the failure process of the key bearing structure into three stages. The pressure relief of the coal pillar and interlayer rock cantilever beam is an effective way to deal with this problem, and the coal pillar instability type needs to be pressure relieved earlier than the cantilever beam instability type. The research findings offer new insights into the roof stability control of mining under the coal pillar.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/1321869","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142084561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the Energy Dissipation Patterns and Fragment Size Distribution Characteristics of Coal Under Cyclic Impact Loading With Confining Pressure","authors":"He Yongliang,&nbsp;Fu Yuping,&nbsp;Li Chuantian,&nbsp;Sun Liying,&nbsp;Zhang Dongya","doi":"10.1155/2024/2113003","DOIUrl":"https://doi.org/10.1155/2024/2113003","url":null,"abstract":"<p>This study examines energy dissipation patterns and failure mechanisms in coal under cyclic impact, crucial for preventing dynamic disasters like rock bursts and coal and gas outbursts. Using a 75-mm split Hopkinson pressure bar (SHPB) experimental system, the dynamic mechanical characteristics and fragment size distribution patterns of coal samples were analysed under a confining pressure of 10 MPa, axial pressure of 12 MPa, and impact pressures of 0.25, 0.30, 0.35, 0.40, and 0.45 MPa for 1, 2, and 3 cycles. The experimental data indicate that as the number of impacts increases, the energy reflected by the coal samples gradually increases, while the transmitted energy correspondingly decreases. The energy absorbed per unit volume of the coal samples under the first, second, and third dynamic loading cycles and confining pressure is 0.56, 0.61, and 0.66 J/cm³, respectively, with energy absorption rates ranging from 16.2% to 33.8%. Under different impact pressures, the fractal dimension of coal fragmentation shows a linear change, and as the impact pressure increases, the degree of fragmentation intensifies, and the mass of the fragmented coal decreases. The strength reduction in the energy dissipation patterns of coal samples under dynamic loading provides important theoretical support for the prevention of rock bursts during coal mining.</p>","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"2024 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/2113003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141994269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}