Energy Exploration & Exploitation最新文献

{"title":"Quantifying the effects of different hydrocarbon charging periods on reservoir quality: A case study of the Upper Wuerhe Formation, Junggar Basin, NW China","authors":"Linjun Huang, Zecheng Wang, S. Pan, Haiguang Wu, D. Xu, Shuai Jiang, Xun Kang","doi":"10.1177/01445987231193043","DOIUrl":"https://doi.org/10.1177/01445987231193043","url":null,"abstract":"Mineral dissolution and precipitation is an important factor affecting pore genesis and hydrocarbon accumulation in sedimentary basins. Differential diagenetic processes at different hydrocarbon charging periods generally cause disparate effects on reservoir quality, which is important for reservoir evaluation and prediction. Focusing on this question, petrologic work, quantitative analysis on reservoir quality including porosity, permeability, and micro-scale X-ray computer tomography were conducted in conglomeratic reservoirs of the late Permian Upper Wuerhe Formation (P3 w) in the Shawan Sag, Junggar Basin, northwestern China. The results show that tuff and volcanic debris are enriched in the formation. Laumontites generally occur as cements in the reservoirs due to the alteration of volcanic materials and small amounts of early-stage calcite precipitated during eodiagenesis. Partial laumontite and calcite cements, as well as some debris and feldspar, are differentially dissolved due to differential hydrocarbon charging. During the continuous compaction of the reservoir, first-stage hydrocarbon charging occurred in the middle Jurassic when primary porosity almost disappeared. Hydrocarbon charging inhibited the precipitation of laumontite and calcite, promoting their dissolution. Second-stage hydrocarbon charging in the early Cretaceous further caused more extensive dissolution of laumontite and calcite, forming more than 70% secondary porosity. Authigenic quartz, kaolinite, and late-stage calcite are precipitated as the associated minerals of laumontite dissolution. This study presents the significance of reservoir reconstruction after hydrocarbon charging and suggests prospective hydrocarbon accumulations in deeply buried clastic reservoirs when hydrocarbon supply is sufficient from source rocks.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132766946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative identification of triassic top unconformity: vertical structure and its reservoir significance in the sanbian area of the ordos basin","authors":"Tongwen Sun, G. Liu, Baiquan Yan, Ming Hu, Zhongyi Zhang, Xiao Hui, Lei Gong, Wei Wang","doi":"10.1177/01445987231191207","DOIUrl":"https://doi.org/10.1177/01445987231191207","url":null,"abstract":"The Triassic top unconformity in the Ordos Basin, which serves as a transfer station for hydrocarbon migration, has become a bottleneck for Mesozoic oil and gas exploration. Taking the Sanbian area as an example, based on core observations, petrophysical properties, and a weathering index analysis of five coring wells, a standard for the quantitative identification of the vertical structure of the unconformity is established using the optimal segmentation method and principal component analysis of conventional logging curves. The standard is then applied to 40 real wells, and 32 typical unconformity reservoirs are dissected. The results show that the reclassification of the unconformity surface corrects the 17.5% error in the geological stratification as an unconformity. On this basis, a quantitative identification standard for the structure of the unconformity is established via the principal component curve. The analysis of unconformity structure types applied to five paleogeomorphic units reveals that the slope mouth and slope develop three layers of structure, namely residual layer, weathered clay layer, and weathered leaching zone, while highlands, river valleys, and inter-river hills lack weathered clay layer. As an independent oil and gas-bearing layer, the unconformity has two types of reservoir-forming models. The first is the hydrocarbon accumulation in the Chang1–Chang2 member shielded by weathered clay layer in the slope mouth and slope. The second is hydrocarbon migrated from the residual layer to the local structural high part of the Yan 10–Yan 9 member in the slope mouth. The hydrocarbon in the unconformity is complementary to the upper Yan 10–Yan 9 member and the lower unweathered rock layer of Yanchang Formation. The results of this study are of great significance to the quantitative identification of unconformity structures in exploration wells without coring data in the study area, as well as to future hydrocarbon exploration in the Mesozoic strata.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125433401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-attribute Probabilistic Neural Network Reservoir Prediction Based on Mudstone Acoustic Time Difference Decompaction Correction","authors":"Feng Guo, Xudong Yang, Ling Guo, Shenghua Lai","doi":"10.1177/01445987231188063","DOIUrl":"https://doi.org/10.1177/01445987231188063","url":null,"abstract":"In order to accurately predict reservoirs with similar physical properties between sandstone and surrounding rocks, this study takes Carboniferous-Permian system in southeastern Ordos Basin as an example, and puts forward a multi-attribute probabilistic neural network prediction method based on acoustic time difference compaction correction. Firstly, the time-frequency analysis method is used to divide the frequency of the original acoustic time difference curve, and the low-frequency long-trend correction of all wells is carried out based on the low-frequency components of standard wells. Then, it is frequency-divided and fused with the original high-frequency components to form new acoustic time difference data, and the long-term trend decompaction correction of acoustic time difference is completed, so that the overlapping area of acoustic time difference between reservoir and surrounding rock is reduced. Multi-attribute probabilistic neural network is an algorithm based on sampling points, before reservoir prediction, inversion parameters must be optimized to save calculation time and reduce prediction error. There is a high correlation between longitudinal velocity and lithologic change trend on the inversion profile of sound velocity. The comparison results of various inversions show that the velocity profile of multi-attribute probabilistic neural network has the highest coincidence rate and high resolution with the velocity curve of logging acoustic wave. The example shows that this method has high accuracy in predicting reservoir thickness, especially for the strata with little difference in physical properties between reservoir and surrounding rock.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116228034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic analysis and numerical simulation of a surface vertical well on the reverse fault side","authors":"Song Qin, H. Lin","doi":"10.1177/01445987231187656","DOIUrl":"https://doi.org/10.1177/01445987231187656","url":null,"abstract":"With the help of mechanical models and numerical calculations, the research obtained: (1) the range of compressive shear stress in well bore is in the shape of “dam body” with the dip angle of a reverse fault, also, the magnitude of the compressive shear stress is related to the load factor and the maximum compressive principal stress which have an increasing relationship; (2) the superposition stress of lateral abutment stress and SZZ of a working face is σA, which is related to the distance between reverse faults; (3) the closer the distance to the reverse fault and the greater the vertical well displacement and deformation as the advancement length of the working face increases, the sensitivity to the effects of the reverse fault and mining is: XDISP > ZDISP > YDISP, and the sensitivity to the boundary is such that: ZDISP > YDISP > XIDSP; (4) the closer the distance to the reverse fault and the larger the length of the working face, the greater the displacement and deformation of the vertical well. In addition, the sensitivity to the effects of reverse faults and mining is: XDISP > ZDISP > YDISP; (5) when the working face continues to be mined, the shear stress on the well bore and the circumference of the hole is sensitive to the influences of reverse faults as follows: SXZ > SYZ > SXY; (7) the density of strain energy at the well bore is most sensitive to the lateral distance to the working face strike mining line. Based on these results, it is proposed to arrange large-diameter pressure relief boreholes around the hole and arrange layers to eliminate the influence of the well bore boundary and eliminate the accumulation of shear strain energy around such a well bore.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"16 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123943585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial distribution characteristics related to carbon cycle and their potential impact on methanogenesis of coal reservoirs in underground in situ environments","authors":"Yang Li, Shuheng Tang, Jian Chen, Z. Xi","doi":"10.1177/01445987231178557","DOIUrl":"https://doi.org/10.1177/01445987231178557","url":null,"abstract":"Microorganisms are one of the main driving forces of the cycle of carbon and other life elements in the underground environment. The natural environment is the comprehensive result of these microorganisms. In contrast, the study of coal reservoir microorganisms is mostly under laboratory conditions, which limits people's understanding of the symbiotic relationship between microorganisms, the interaction between microorganisms and the environment, and the distribution differences of microbial communities in the region. Similarly, the carbon cycle of the underground environment driven by essential microorganisms in coal reservoirs cannot be further studied. The geochemical process of underground methane generation and oxidation is critical in discussing the production and consumption of biomethane in the underground environment and the metabolic behavior of microorganisms. For this reason, we conducted biogeochemical tests and microbial sequencing on the water produced by coalbed methane wells in the south of the Qinshui Basin to analyze and improve the understanding of the distribution difference and metabolic behavior of microbial communities in coal reservoirs. The concentration of Cl− and HCO3− in the detention environment in the study area increases, while the concentration of SO42−, NO3−, NO2−, and Fe3+ decreases with the increase of coal seam depth, reflecting the distribution difference of hydrochemical environment and redox conditions of the underground reservoir in the study area. The results of microbial sequencing showed microbial methanogenesis in the study area, but it could also be consumed by microbial oxidation simultaneously. The microbial communities related to methane production and consumption had diversity distributions similar to geochemical parameters and geographical patterns. Methanogens and dissolved inorganic carbon isotopes confirmed the potential of in situ methane generation. Still, biomethane's enrichment and accumulation conditions and the impact of aerobic/anaerobic oxidation of methane need further study.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115464522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of surrounding rock heat dissipation and wind temperature prediction in high geotemperature coal face","authors":"Hao Wang","doi":"10.1177/01445987231187658","DOIUrl":"https://doi.org/10.1177/01445987231187658","url":null,"abstract":"The heat damage in a coal face of a high-temperature mine is a significant mine disaster owing to various heat sources. Understanding the influence of various heat sources on the air temperature distribution in the coal face can help us to determine reasonable working conditions. Therefore, it is necessary to take into account the coupling relationship of multiple heat sources and obtain accurate prediction results. In this paper, the finite volume calculation method is used to establish a numerical model of heat dissipation of surrounding rock considering the difference in thermal and physical properties of coal and rock in the coal face. And then, a high-temperature coal mine in the northeast of China is taken as an example to explore the airflow temperature distribution law of the coal face under the influence of the absolute heat source and the relative heat source via the finite difference method. Furthermore, an orthogonal test was performed to investigate the influence degree of major factors on heat exchange of the coal face through range analysis. This work supplements the existing numerical model and research, and provides a theoretical basis and more accurate practical methods for predicting the thermal environment of coal face, especially in high mining depth mines.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128264751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of vertical variation of coal seam structure on hydraulic fracturing and resultant gas and water production: A case study on the Shizhuangnan Block, Southern Qinshui Basin, China","authors":"Guoqiao Yang, Wenhui Hu, Shuheng Tang, Zhuoming Zhou, Zhen-duo Song","doi":"10.1177/01445987231177471","DOIUrl":"https://doi.org/10.1177/01445987231177471","url":null,"abstract":"Hydraulic fracturing plays a vital role in the development of coalbed methane (CBM). Coal seam structures can, however, affect the fracturing operations, further affecting gas and water production from the coal seam. Within the research area—the Shizhuangnan Block, Southern Qinshui Basin, China—three types of coal body textures are relevant, including original, cataclastic, and granulated structure. This research describes the impacts of different coal seam types on fracturing operations and gas and water production. The results show that different types of coal seams have different impacts on hydraulic fracturing and the resultant production of gas and water. The coal seams are classified according to the vertical variation characteristics of the coal seam structures. The first type of coal seam (Type I) only develops the original and cataclastic coal structure. The effects of fracturing reconstruction for Type I are good. A high degree of coal breakage and fracture formation is observed. Gas production from CBM wells in Type I coalbeds is usually high because the water in the coal reservoir can be discharged smoothly at an early stage. The second type of coal seam (Type II) develops an additional layer of granulated coal compared with Type I. During the fracturing process, breakage of the coal seam is obvious, and the granulated coal can easily produce fine-grained coal that can block the pores and fractures, which causes an increase and fluctuation of oil pressure and can affect the effectiveness of fracturing. The gas production curve from CBM wells in Type II coal seams is mostly bimodal and water production depends on whether the pulverized coal blocks the pores and fractures. The third type of coal seam (Type III) develops two additional layers of granulated coal compared with Type I, with a greater proportion of granulated coal present. A low degree of coal breakage and fracture formation is observed, and fractures are easily blocked by pulverized coal. The effects of fracturing reconstruction for Type III are bad. Forming an effective seepage channel in this type of coal seam and extending the fracture to the far end is difficult. The gas production from CBM wells in Type III coal seams is usually low, and water production is generally low during the whole drainage period.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127903001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling and characteristic analysis of viscous resistance in annulus gap of coalbed gas well drainage pump","authors":"Hao Hu, Fenglian Zhang, Chuan-kai Jing, Bin Wang, Ying-ying Zhang, Y. Qi","doi":"10.1177/01445987231188531","DOIUrl":"https://doi.org/10.1177/01445987231188531","url":null,"abstract":"The viscous resistance caused by the relative motion of plunger and pump barrel is an important factor in the dynamic analysis of the drainage and production mechanism during coalbed methane exploitation. Existing studies mostly focus on deep well (1000–3000 m) large-displacement pump (usually 80–300 m3/d), and the interstitial medium is mainly crude oil. Regression fitting is mainly carried out based on empirical formula or experimental simulation method, without considering the characteristics of shallower coalbed gas well (400–800 m) small-displacement pump (<10 m3/d). The variation of the clearance between plunger and barrel and the variation of viscous resistance between plunger and barrel are not revealed. Based on the Navier-Stokes equation and Newton's internal friction law, a mathematical model of the annular viscous resistance between the plunger and the pump barrel is established, and an analytical method is used to describe the influence of stroke times, annular clearance, and differential pressure between the upper and lower plungers on the viscous resistance. The results show that the plunger stroke is directly proportional to the variation range of viscous resistance, and low stroke is beneficial to reduce the viscous resistance. The effect of differential pressure between upper and lower plunger of rod pump on viscous resistance of small displacement coalbed gas well is significantly greater than that of plunger running speed. The annular clearance is directly proportional to the differential pressure between the upper and lower parts of the plunger, the inertia force of the plunger, and the shear force of the moving fluid. The annular viscous resistance model between plunger and pump barrel is helpful to improve the calculation accuracy of suspending point load of coalbed gas well pumping unit, analyze the working condition of coalbed gas drainage gas production process, and provide basis for the optimization design of coalbed gas well rod pump clearance.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126502575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical characteristics and their implication of light hydrocarbons in natural gas from the Lower Paleozoic carbonate reservoirs in the Daniudi gas field, Ordos Basin","authors":"Xiaoqi Wu, Ping Wang, Chunhua Ni, Yingbin Chen, Jianhui Zhu","doi":"10.1177/01445987231185886","DOIUrl":"https://doi.org/10.1177/01445987231185886","url":null,"abstract":"The genetic types and source of the Lower Paleozoic natural gas in the Ordos Basin in China are controversial, and the geochemical characteristics of light hydrocarbons of natural gas in the fifth member of the Ordovician Majiagou Formation (O1m5) are studied by taking the Daniudi gas field as an example, in order to reveal the gas origin and source. The C5−7 light hydrocarbons are dominated by iso-alkanes rather than the n-alkanes, and the methyl cyclohexane (MCH) content is mostly higher than the nC7 content in C7 light hydrocarbons. The K1 and K2 values range from 1.06 to 1.16 and from 0.33 to 0.81, respectively. The geochemical characteristics of light hydrocarbons indicate that the Lower Paleozoic natural gas in the Daniudi gas field is mainly coal-derived gas which has been generated by the humic source rocks in the Upper Carboniferous Taiyuan Formation (C3t), with insignificant contribution by the O1m sapropelic source rocks. The O1m5 gas pools were accumulated through downward and lateral migration in the free phase. The aromatic contents in C6-7 and nC7/MCH ratios are easily affected by the factors such as water solubilization, adsorption in migration, evaporation, and migration fractionation, therefore, secondary alteration needs to be considered when using these parameters to identify the gas origin.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123294800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A class of nonlinear multi-objective mixed integer programming model for oil and gas portfolio and algorithm solution","authors":"Wei Yan","doi":"10.1177/01445987231182448","DOIUrl":"https://doi.org/10.1177/01445987231182448","url":null,"abstract":"This paper is concerned with the oil & gas assets portfolio. A multi-objective portfolio model of oil & gas assets is studied from two perspectives—scale and revenue. Considering the nonlinear and integer constraints in the model, a class of oil & gas assets portfolio model of nonlinear multi-objective mixed integer programming is established. The weight of the multi-objective is solved by the support vector machine model. A hybrid genetic algorithm, which uses the position displacement strategy of the particle swarm optimizer as a mutation operation, is applied to the optimization model. Finally, two examples are applied to verify the effectiveness of the model and algorithm.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121748061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}