Geofluids最新文献

{"title":"Heat Transfer Analysis of Enhanced Geothermal System Based on Heat-Fluid-Structure Coupling Model","authors":"Linchao Wang, Xin Liang, Xuyang Shi, Jianyong Han, Yang Chen, Wan Zhang","doi":"10.1155/2023/8840352","DOIUrl":"https://doi.org/10.1155/2023/8840352","url":null,"abstract":"Dry hot rock geothermal resources by virtue of its wide distribution, large reserves, clean and low-carbon, stable, high utilization rate, and other characteristics have been widely used. The enhanced geothermal system (EGS) is the most efficient approach for harnessing and exploiting geothermal energy from hot, arid rock formations. To investigate the impact of varying parameters on heat recovery in EGS operations, we employed the COMSOL numerical simulation software to construct a seepage heat transfer model for fractured rock masses. Essential parameters and boundary conditions were established, followed by conducting numerical simulations. Through the numerical simulation results, the temporal and spatial changes of coupling effects among seepage field, stress field, and temperature field in fractured rock mass were analyzed. We investigated the impact of water injection temperature, injection-production pressure difference, injection flow rate, and initial reservoir temperature on the heat transfer process. The findings indicate that raising the water injection temperature and injection-production pressure difference can enhance the reservoir’s heat recovery capability. However, it may also accelerate thermal breakthrough and reduce the system’s operational lifespan. The higher injection flow rate can improve the heat recovery efficiency. However, too large injection flow can cause problems in other aspects of the reservoir; increasing reservoir temperature leads to higher production temperatures, which can potentially result in dynamic catastrophes. Therefore, while ensuring the heat recovery efficiency of the system, the operation life of the system can be extended by adjusting the water injection temperature in stages, setting a reasonable injection and production pressure difference, and selecting an appropriate injection flow rate, so as to achieve the purpose of EGS optimization.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"11 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138533962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fracture Initiation and Propagation in the Hot Dry Rock Subject to the Cyclic Injection Hydraulic Fracturing Treatment","authors":"Yilong Yuan, Wei Wang, Jiawei Tang, Qiang Guo, Yulong Liu","doi":"10.1155/2023/8859177","DOIUrl":"https://doi.org/10.1155/2023/8859177","url":null,"abstract":"Cyclic injection hydraulic fracturing is a promising way for the geothermal energy exploitation by reactivating the fractures in geothermal reservoir. However, fracture initiation and growth induced by cyclic injection schemes have been inadequately studied for hot dry rock (HDR), and the cyclic injection fracturing optimized often by experience. For this reason, the initiation and propagation of hydraulic fractures in the HDR under different cyclic injection methods were determined by experiment research for hydraulic fracturing. The results show that the cyclic frequency and injection rate play different roles in the stimulation of HDR. The cyclic injection with low frequency-low pressure can create more branched fractures, forming a short but complex hydraulic fracture network. However, when high flow-high frequency injection method is subjected, the branch fractures formed are significantly reduced, but each branch fracture can be fully expanded. To fully exploit the advantages of different injection methods, a numerical model that contains a fracture network was established with PFC software, and an alternating cyclic injection scheme with synergistic control of the cyclic frequency and injection rate was proposed. The comparison results indicated that the alternating cyclic injection method can effectively improve the fracturing effect in the HDR. The stimulation area of the alternating cyclic injection method is about 2.3 times and 2.7 times that of the low flow-low frequency and high flow-high frequency injection methods, respectively. The method presented here can be adopted to optimize the fracture growth regime and provide a scientific basis for EGS hydraulic fracturing design.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"59 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138533961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Microscopic Pore Network Characteristics on Movable Fluid Properties in Tight Oil Reservoir","authors":"Jie Gao, Hu Wang, Xiaojun Ding, Qingxiao Yuchi, Qiang Ren, Bo Ning, Junxiang Nan","doi":"10.1155/2023/7464640","DOIUrl":"https://doi.org/10.1155/2023/7464640","url":null,"abstract":"The fluid flow behavior, generally referred to as seepage, could determine the hydrocarbon and brine movement behavior. Movable fluid property, as one of the vital parameters for seepage characteristic evaluation, was generally used for tight oil reservoirs’ fluid flow ability assessment. The nuclear magnetic resonance technique was used to experiment with movable fluid percentage and movable fluid porosity, which can provide a realistic assessment of the amount of fluid that can flow in the porous media. Other techniques were also used to analyze the main factors in regulating the differences in movable fluid parameters. However, the research about fluid flow behavior was generally based on traditional methods, while the seepage characteristics from the pore-scale view are still a myth. To promote this process, in this study, core samples obtained from the Chang 7 reservoir of the Triassic Yanchang Formation in the Longdong region of Ordos Basin, China, were tested. The results show that the average movable fluid percentage and average movable fluid porosity of the total 16 core samples are 36.01% and 2.77%, respectively. The movable fluid exists mainly in the midlarge pores with the corresponding <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M1\"> <msub> <mrow> <mi>T</mi> </mrow> <mrow> <mn>2</mn> </mrow> </msub> </math> relaxation time over 10 ms. <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M2\"> <msub> <mrow> <mi>T</mi> </mrow> <mrow> <mn>2</mn> </mrow> </msub> </math> distributions mainly present four typical patterns: (1) bimodal distribution with similar amplitudes of the two peaks (occupying 6.25%), (2) bimodal distribution with higher right peak and lower left peak (occupying 18.75%), (3) bimodal distribution with higher left peak and lower right peak (occupying 56.25%), and (4) unimodal distribution (occupying 18.75%). Pore structure heterogeneity is closely related to the movable fluid parameters; the movable fluid parameters exhibit a relatively good correlation with core throat radius as well as permeability. There is an obvious difference between the movable fluid parameters and the microscopic characteristic factors in tight oil reservoirs due to the difference in physical properties, clay mineral content, microcracks, and pore structure characteristics. This research has provided a new perspective for the movable fluid property evaluation, and the relevant results can give some advice for the oil field development.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"19 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134956685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Water Saturation on Adsorption Behavior at Liquid-Liquid Interfaces in Unsaturated Porous Media","authors":"Yan Zhu, Ziteng Cui, Kun Li, Chaoqi Wang, Zhao Li, Xueyi Zhang, Zhi Dou","doi":"10.1155/2023/8155349","DOIUrl":"https://doi.org/10.1155/2023/8155349","url":null,"abstract":"Adsorption reaction in unsaturated porous media is of great importance for soil and groundwater remediation. In this study, the influence of the Peclet number (Pe) and water saturation on adsorption behavior at liquid-liquid interfaces was quantitatively investigated. The pore-scale reactive transport in unsaturated porous media was directly simulated. The Navier-Stokes equations, the surface transfer and adsorption reaction equations, and the advection-diffusion equation (ADE) were coupled to obtain the flow and concentration fields. The results showed that water saturation had a significant influence on the complexity of the flow field. A nonmonotonic relationship was found between water saturation and the uniformity of the flow field. Peclet number had little influence on the maximum adsorption. On the other hand, the adsorption time showed a nearly linear relationship with the Peclet number and increased with increasing Peclet number. Additionally, a nonlinear relationship was found between water saturation and the maximum adsorption. As water saturation increased, the maximum adsorption tended to increase to a peak and then decrease. The peak of the maximum adsorption occurred at <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M1\"> <mtext>Pe</mtext> <mo>=</mo> <mn>5</mn> </math> , <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M2\"> <msub> <mrow> <mi>S</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> <mo>=</mo> <mn>0.458</mn> </math> , and the shortest adsorption time was observed at <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M3\"> <msub> <mrow> <mi>S</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> <mo>=</mo> <mn>0.902</mn> </math> . However, the difference in adsorption times for saturations of 0.458 and 0.698 was not significant and was only about 20 PV difference.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":" 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135291153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the Impact of Leaching Agent Concentration and pH on the Stability of Agglomeration of Ion-Absorbed Rare Earth Deposits","authors":"Zhongquan Gao, Yunzhang Rao, Liang Shi, Xiaoming Zhang, Run Xiang","doi":"10.1155/2023/6333122","DOIUrl":"https://doi.org/10.1155/2023/6333122","url":null,"abstract":"Ion-absorbed rare earth deposits react with the leaching agent during the in situ leaching process through ion exchange and hydration, which change the stability of ore agglomerates and even result in mining slopes or landslides. Indoor simulated column leaching assays were conducted on ion-absorbed rare earth deposit samples by using magnesium sulfate solution as the leaching solution. Surface zeta potential, double electric layer thickness, particle gradation, and pore structure were analyzed to measure the different concentrations and pHs of leaching solutions’ impact on the stability of ore agglomerates. Results show that the critical magnesium sulfate solution concentration and pH affecting the stability of deposit sample agglomerates are 3.5% and 4, respectively. The chemical replacement reaction between the leaching agent and rare earth ions occurs during column leaching when it reaches its zero-point potential at a pH of 3.5168. This breaks the balance between the van der Waals gravitational force and double-layer repulsion in clay particles and induces the disruption of agglomerates, which causes the difference in the pore radius ratio of the ore samples before and after column leaching. It is of great engineering guidance to solve the problems of slope instability and landslides that may occur in the ore body during the mining process of ionic rare earth ore.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"35 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134973623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reactive Transport Modelling of Elevated Dissolved Sulphide Concentrations in Sedimentary Basin Rocks","authors":"Mingliang Xie, Danyang Su, Kerry T. B. MacQuarrie, K. Ulrich Mayer","doi":"10.1155/2023/7435602","DOIUrl":"https://doi.org/10.1155/2023/7435602","url":null,"abstract":"Groundwater with total dissolved sulphide concentrations in excess of <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M1\"> <mn>1.0</mn> <mo>×</mo> <msup> <mrow> <mn>10</mn> </mrow> <mrow> <mo>−</mo> <mn>4</mn> </mrow> </msup> <mtext> </mtext> <mtext>mol</mtext> <mtext> </mtext> <msup> <mrow> <mtext>L</mtext> </mrow> <mrow> <mo>−</mo> <mn>1</mn> </mrow> </msup> <mtext> </mtext> <mfenced open=\"(\" close=\")\"> <mrow> <mn>3</mn> <mtext> </mtext> <mtext>mg</mtext> <mtext> </mtext> <msup> <mrow> <mtext>L</mtext> </mrow> <mrow> <mo>−</mo> <mn>1</mn> </mrow> </msup> </mrow> </mfenced> </math> is relatively common at intermediate depths in sedimentary basins. However, the mechanisms responsible for the formation and spatial distribution of these sulphidic waters in sedimentary basins, which have been affected by periods of glaciation and deglaciation, are not fully understood. Sulphate reduction rates depend on many factors including redox conditions, salinity, temperature, and the presence and abundance of sulphate, organic matter, and sulphate-reducing bacteria. Two-dimensional reactive transport modelling was undertaken to provide potential explanations for the presence and distribution of sulphidic waters in sedimentary basins, partially constrained by field data from the Michigan Basin underlying Southern Ontario, Canada. Simulations were able to generally reproduce the observed depth-dependent distribution of sulphide. Sulphate reduction was most significant at intermediate depths due to anoxic conditions and elevated sulphate concentrations in the presence of organic matter in waters with relatively low salinity. The simulations indicate that glaciation-deglaciation periods increase mixing of waters at this interfacial zone, thereby enhancing rates of sulphate reduction and the formation of sulphide. In addition, the simulations indicate that glaciation-deglaciation cycles do not significantly affect sulphide concentrations in low permeability units, even at shallow depths (e.g., 25 m), while concentrations in permeable units remain stable below depths of 500 m.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134974253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying Effective Rock-Breaking Ratio Based on Rock Chip Information for Rock-Breaking Efficiency Evaluation of TBM","authors":"Chuigang Zeng, Changbin Yan, Gaoliu Li, Xiao Xu, Fengwei Yang, Weilin Su","doi":"10.1155/2023/1576401","DOIUrl":"https://doi.org/10.1155/2023/1576401","url":null,"abstract":"The rock chip information (shape, size, and particle size distribution) could comprehensively reflect the characteristics of rock mass and rock-breaking efficiency of TBM. This study is aimed at defining a novel index (effective rock-breaking ratio, <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M1\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> ) to identify the rock-breaking efficiency of TBM based on the rock chip information. To evaluate this approach, a series of field sieving and measuring tests of rock chips was conducted at the water conveyance tunnel construction projects of China. The rock-breaking efficiency evaluation and tunneling parameter improvement of TBM were researched based on <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M2\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> index. The results showed as follows: (1) from the perspective of energy conversion, the rock chip surface area was calculated through the rock chip cumulative volume distribution model. <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M3\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> is used to evaluate the rock-breaking efficiency of TBM based on the proportion of surface area of rock chips with particle size larger than 5 mm; (2) <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M4\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> has a good linear correlation with coarseness index (CI) and specific energy (SE), the higher the TBM tunneling efficiency, the larger <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M5\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> and CI values, the less SE values; (3) <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M6\"> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mtext>r</mtext> </mrow> </msub> </math> increases at first and then decreases with the rise of thrust force of TBM. The optimal thrust force intervals for grade II and III surrounding rocks can be determined to improve the rock-breaking efficiency of TBM. Findings from this study are insightful in terms of accurately evaluating the excavation efficiency and improving the tunneling parameters of TBM.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"94 1-2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135217070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Water Content on the Impact Propensity of White Sandstone","authors":"Jiankui Bai, Chuanming Li, Ruimin Feng, Nan Liu, Xiang Gao, Zhengrong Zhang, Bochao Nie","doi":"10.1155/2023/8839852","DOIUrl":"https://doi.org/10.1155/2023/8839852","url":null,"abstract":"Impact ground pressure is one of the most common dynamic disasters induced by mining activities, and water content is an important factor affecting such dynamic disasters. In this paper, uniaxial compression test, cyclic loading and unloading test, and acoustic emission test were conducted on white sandstone using RMT-150B rock mechanics test system and DS5 acoustic emission test system. The influence law of water content was analyzed on the strength characteristics, energy change characteristics, and impact propensity of white sandstone. The results showed that (1) the internal structure of the sandstone gets softened with the increase of the water content. The cohesive effect within the rock also begins to weaken, which in turn reduces the stiffness of the material and enhances its plasticity. The ability of the rock to resist elastic deformation becomes weaker, resulting in lower compressive strength and elastic modulus when the rock is subjected to external forces, making it more prone to deform and fail. The decrease in compressive strength of the water-saturated rock is 33.3%, and the decrease in its elastic modulus is 28.1% compared to the dry rock. (2) As the water content increases, the cohesion of the rock decreases and the internal structure of the rock fails more easily, which ultimately makes the energy needed for rock destruction lower. As a result, the total energy, elastic energy, and dissipative energy of the rock are reduced. The accumulated AE energy also decreases with the increase of the water content, indicating that rocks with higher water content gather less elastic energy before damage and accumulate less energy when deformation damage occurs. (3) The impact energy index and elastic energy index are negatively correlated with the water content. The impact energy index is reduced by 28.6%, and the elastic energy index is reduced by 20.9% for the saturated rock compared to the dry rock. The elastic energy index and impact energy index both decrease with the increase of rock water content, indicating that the less elastic energy is stored before the destruction of the rock and no excess energy is transformed into energy in rock crushing when the rock breaks, and therefore, the impact propensity of the rock is smaller. The results of the study can provide a theoretical basis for underground construction as well as rock fracture destabilization.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135994375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Fracture Evolution and Failure Characteristics of Rocks under High-Temperature Liquid Nitrogen Interaction","authors":"Linchao Wang, Yi Xue, Xuyang Shi, Zhihao Zhang, Xue Li, Lin Zhu, Ruifu Liu, Lin Sun, Caifang Wu, Songbao Feng","doi":"10.1155/2023/6664383","DOIUrl":"https://doi.org/10.1155/2023/6664383","url":null,"abstract":"The utilization of liquid nitrogen as a sustainable and water-free fracturing medium exhibits immense promise in engineering applications. In this investigation, Brazilian split tests and acoustic emission tests were conducted to explore the impact of liquid nitrogen cooling on the internal structure and mechanical properties of rock specimens. To examine the influence of liquid nitrogen cooling on the tensile strength of rocks, displacement-load curves were obtained from samples subjected to varying cycles of high-temperature liquid nitrogen cooling using Brazilian split tests. Acoustic emission experiments were conducted to investigate the characteristics of granite samples exposed to various cycles of high-temperature liquid nitrogen cooling. Based on these findings, the impact of liquid nitrogen cooling on the internal structure of rock masses was analyzed. The findings of this study demonstrate that high-temperature liquid nitrogen thermal treatment significantly modifies the microscopic structure and mechanical properties of rocks, with potential implications for overall stability and reliability. Notably, an observable decline in tensile strength was observed as the number of cycles of high-temperature liquid nitrogen treatment increased. These findings underscore the substantial impact of liquid nitrogen cooling on the behavior of rocks. High-temperature liquid nitrogen treatment effectively promotes the generation of microcracks within rocks, thereby increasing their permeability. During the experiment, granite specimens primarily exhibited shear-type fractures when subjected to high-temperature freeze-thaw cycles induced by liquid nitrogen.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136033952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlling Factors of Organic-Rich Lacustrine Shale in the Jurassic Dongyuemiao Member of Sichuan Basin, SW China","authors":"Yadong Zhou, Chan Jiang, Dongfeng Hu, Zhihong Wei, Xiangfeng Wei, Daojun Wang, Jingyu Hao, Yuqiang Jiang, Yifan Gu","doi":"10.1155/2023/3380389","DOIUrl":"https://doi.org/10.1155/2023/3380389","url":null,"abstract":"Organic-rich continental shale, widespread in the Sichuan Basin during the deposition of the Jurassic Dongyuemiao Member (J1d), is considered the next shale hydrocarbon exploration target in southern China. To identify a shale gas sweetspot and reduce exploration risk, it is of great significance to determine the organic matter (OM) enrichment mechanism of J1d shale. In this study, based on sedimentological characteristics and organic matter content, high-resolution major and trace elements were systematically analyzed to demonstrate terrigenous influx, paleoredox, paleosalinity, paleoproductivity, and paleoclimate. The 1st section interval of the J1d 1st submember is dominated by shallow lake subfacies, while the other intervals have the characteristic of semideep to deep lake subfacies. The 1st submember interval of J1d lacustrine shale is characterized by the warmest-humid paleoclimate, strongest weathering degree, highest terrigenous input, moderate paleoproductivity, and paleoredox condition. Within the Dongyuemiao 1st submember, the 4th section interval has the highest paleoproductivity and the most oxygen-deficient condition in bottom water. During the deposition period of the 2nd submember, the sedimentary environment turned to a cold-dry paleoclimate, weak weathering degree, low terrigenous input, low paleosalinity, and high paleoproductivity. Under the background of semideep and deep lake, the terrigenous OM input plays the most critical role in controlling OM enrichment. Moreover, the high primary productivity of lake surface water and the suboxic condition of lake bottom water contribute to the formation of relatively higher TOC lacustrine shale interval in the 4th section of 1st submember.","PeriodicalId":12512,"journal":{"name":"Geofluids","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136063116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}