Petroleum Research最新文献

{"title":"Experimental study of cryogenic treatment of Karaganda coal samples","authors":"","doi":"10.1016/j.ptlrs.2024.01.009","DOIUrl":"10.1016/j.ptlrs.2024.01.009","url":null,"abstract":"<div><p>Karaganda Coal Basin bears the largest undeveloped reserve of coalbed methane (CBM) in Kazakhstan, which lacks water resources for implementing large-volume hydraulic fracturing. Cryogenic fracturing utilizing liquid nitrogen (LN₂) has been trialled in fields and is a waterless fracturing technique under intensive research these days. This study aimed to evaluate the cryogenic treatment efficacy of Karaganda coal samples as well as to understand the coal permeability evolution during the thawing period. X-ray fluorescent spectrometry (XRF) and microscope imaging identified the compositional and structural heterogeneities of coal specimens mined from different interlayers. Acoustic emission test, permeability measurement, and microscope imaging comparatively characterized the dry coal structure alteration before and after immersion into LN₂. Cryogenic treatment slowed down the S-wave velocity through coal specimens, enhanced permeability by over 65 % after temperature recovery as well as created new fractures, enlarged existing ones, and spalled coal particles. Dynamic permeability evolution against temperature rise during the thawing process has been successfully captured for the first time. Overall, the experimental measurements support that the LN₂ cryogenic fracturing technique would be effective in stimulating coalbeds for CBM production in Karaganda Coal Basin.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 359-368"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000097/pdfft?md5=0034f02e03da25e3cd32fd3ee36c5989&pid=1-s2.0-S2096249524000097-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140521080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing production monitoring: A back allocation methodology to estimate well flow rates and assist well test scheduling","authors":"","doi":"10.1016/j.ptlrs.2024.03.008","DOIUrl":"10.1016/j.ptlrs.2024.03.008","url":null,"abstract":"<div><p>Production flow rates are crucial to make operational decisions, monitor, manage, and optimize oil and gas fields. Flow rates also have a financial importance to correctly allocate production to fiscal purposes required by regulatory agencies or to allocate production in fields owned by multiple operators. Despite its significance, usually only the total field production is measured in real time, which requires an alternative way to estimate wells’ production. To address these challenges, this work presents a back allocation methodology that leverages real-time instrumentation, simulations, algorithms, and mathematical programming modeling to enhance well monitoring and assist in well test scheduling. The methodology comprises four modules: simulation, classification, error calculation, and optimization. These modules work together to characterize the flowline, wellbore, and reservoir, verify simulation outputs, minimize errors, and calculate flow rates while honoring the total platform flow rate. The well status generated through the classification module provides valuable information about the current condition of each well (i.e. if the well is deviating from the latest well test parameters), aiding in decision-making for well testing scheduling and prioritizing. The effectiveness of the methodology is demonstrated through its application to a representative offshore oil field with 14 producing wells and two years of daily production data. The results highlight the robustness of the methodology in properly classifying the wells and obtaining flow rates that honor the total platform flow rate. Furthermore, the methodology supports well test scheduling and provides reliable indicators for well conditions. By utilizing real-time data and advanced modeling techniques, this methodology enhances production monitoring and facilitates informed operational decision-making in the oil and gas industry.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 369-379"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000334/pdfft?md5=0d8dfdd673fe76cb33ab681e72fb9855&pid=1-s2.0-S2096249524000334-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140280328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applicability of deep neural networks for lithofacies classification from conventional well logs: An integrated approach","authors":"","doi":"10.1016/j.ptlrs.2024.01.011","DOIUrl":"10.1016/j.ptlrs.2024.01.011","url":null,"abstract":"<div><p>Parametric understanding for specifying formation characteristics can be perceived through conventional approaches. Significantly, attributes of reservoir lithology are practiced for hydrocarbon exploration. Well logging is conventional approach which is applicable to predict lithology efficiently as compared to geophysical modeling and petrophysical analysis due to cost effectiveness and suitable interpretation time. However, manual interpretation of lithology identification through well logging data requires domain expertise with an extended length of time for measurement. Therefore, in this study, Deep Neural Network (DNN) has been deployed to automate the lithology identification process from well logging data which would provide support by increasing time-effective for monitoring lithology. DNN model has been developed for predicting formation lithology leading to the optimization of the model through the thorough evaluation of the best parameters and hyperparameters including the number of neurons, number of layers, optimizer, learning rate, dropout values, and activation functions. Accuracy of the model is examined by utilizing different evaluation metrics through the division of the dataset into the subdomains of training, validation and testing. Additionally, an attempt is contributed to remove interception for formation lithology prediction while addressing the imbalanced nature of the associated dataset as well in the training process using class weight. It is assessed that accuracy is not a true and only reliable metric to evaluate the lithology classification model. The model with class weight recognizes all the classes but has low accuracy as well as a low F1-score while LSTM based model has high accuracy as well as a high F1-score.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 393-408"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000115/pdfft?md5=c4ce8ee0a3e7702bf4c40dd4a2df687b&pid=1-s2.0-S2096249524000115-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139830653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentary microfacies of Member 5 of Xujiahe Formation in the Dongfengchang area, Sichuan Basin","authors":"","doi":"10.1016/j.ptlrs.2024.03.003","DOIUrl":"10.1016/j.ptlrs.2024.03.003","url":null,"abstract":"<div><p>Member 5 of the Upper Triassic Xujiahe Formation (T₃X₅) in central Sichuan Basin has made a breakthrough in exploration recently. However, this new stratum has not been investigated sufficiently with respect to basic geology, making its types and distribution of sedimentary facies unclear, which severely restricts its subsequent exploration evaluation. In this study, types of sedimentary microfacies in the first sand group of T₃X₅ (T₃X₅¹) are clarified through core observation and logging interpretation using core, log and seismic data, and then distribution of sedimentary microfacies in T₃X₅¹ is determined according to seismic waveform features and seismic prediction. The results show that T₃X₅¹ in the Dongfengchang area is mainly composed of deltaic deposits of several microfacies, such as delta front underwater distributary channel, sheet sand, and interdistributary bay. On seismic sections, different microfacies are significantly different in waveform features, the underwater distributary channel is characterized by one trough between two peaks, while diversion bay exhibits chaotic reflections between T6 and T51. The sedimentary microfacies varied greatly during the depositional period of T₃X₅¹ in the Dongfengchang area, this is because that the sediment supply was mainly controlled by the southwest and southeast provenance regions. Three superimposed underwater distributary channels are developed in the Dongfengchang area. The phase-1 superimposed underwater distributary channel in the northwest transition to sheet sand in the northeast, the phase-2 superimposed underwater distributary channel in the south extends shortly, the phase-3 superimposed underwater distributary channel in the northeast has a large development scale. These research findings are helpful to guide the subsequent exploration of T₃X₅ gas reservoir and also theoretically significant for investigating the depositional evolution of the Xujiahe Formation in central Sichuan Basin.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 481-488"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000280/pdfft?md5=63220efd67ba9e4bf473870d465733c3&pid=1-s2.0-S2096249524000280-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140268223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of graphs to assess well safety in drilling projects and during operations by identification of available barrier elements and consolidation of barrier envelopes","authors":"","doi":"10.1016/j.ptlrs.2024.02.002","DOIUrl":"10.1016/j.ptlrs.2024.02.002","url":null,"abstract":"<div><p>Two independent barrier envelopes are the usual requirement used in most well operations to avoid catastrophic accidents. These are classified as primary – concerning preventing the occurrence of a kick, and secondary – concerning controlling the kick to avoid a blowout. Barrier envelopes consist of barrier elements, thus verifying the quality of these elements is fundamental. Barrier elements may be either redundant or mandatory, and these relationships are what constitute the barrier envelopes. In this work, we present a methodology to evaluate well safety by identifying existing barrier elements and barrier envelopes and mapping their relationships through the usage of graphs technique. This technique explicitly states the relationship between barriers and between them and envelopes. It enables a simpler visualization for well designers and allows the development of computer programs to control the safety and integrity of wells, both in the design phase and during drilling. 12 graphs are provided for a 4-phase well (conductor, surface, production, and drill-in), considering both the primary and secondary envelopes. Reasoning for constructing each graph is thoroughly provided. If these graphs are used, reliability values can then be assigned to each barrier element, which results in the reliability of entire barrier envelopes. This can be further extended to analyze the safety of each operation by applying the system to operational sequences and even comparing well designs.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 418-431"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000255/pdfft?md5=99ec4494e7d1c016bf43f10c75fdb671&pid=1-s2.0-S2096249524000255-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140084462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on slim-hole drilling technology for shale gas geological survey in China","authors":"","doi":"10.1016/j.ptlrs.2024.03.006","DOIUrl":"10.1016/j.ptlrs.2024.03.006","url":null,"abstract":"<div><p>Over the last 10 years, the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores. These wells are primarily located in new blocks and geological formations where neighboring well data are insufficient, beyond the scope of developed oil fields in China, or outside of oil and gas company mining-right areas. The drilling rig equipment, coring tools, and core drill bits of slim-hole shale gas drilling technology are different from those associated with traditional petroleum drilling. Many studies have been conducted on non-coring slim-hole drilling technology. This paper focuses on coring technology and drilling safety, summarizing a set of high-efficiency shale gas drilling equipment and technology systems based on geological drilling equipment and techniques (that can be used for solid mineral exploration). We report on: 1) an improved vertical shaft drilling rig adapted to shale gas well control safety; 2) high-efficiency core drilling techniques, focusing on coring tools, and techniques incorporating an inverted tower drilling tool combination, air circulation follow-through technology, and expanded casing technology; 3) research progress on high-efficiency core drill bits, including non-planar tooth polycrystalline diamond compact bits and impregnated diamond core bits, along with their application effects. This research provides substantial advances in drill-core technology and improvements in exploration efficiency. Moreover, it provides a reference frame for well structural design and selection of construction technology for shale gas exploration drilling projects.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 451-461"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000322/pdfft?md5=644a46f277292c005d866fc0c42b587d&pid=1-s2.0-S2096249524000322-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140400036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Empirical study of magnetohydrodynamic effect on fluid flow in clayey porous media","authors":"","doi":"10.1016/j.ptlrs.2024.03.010","DOIUrl":"10.1016/j.ptlrs.2024.03.010","url":null,"abstract":"<div><p>Enhancing oil recovery from clayey reservoirs is a significant challenge in petroleum industry due to complex interactions between fluids and rock surfaces, particularly clay swelling. This study presents the first empirical analysis of magnetic fields' impact on fluid flow in clayey porous media. Our core findings indicate that magnetic treatment of water increases oil recovery by an average of 15–30% in clayey media, with limited effectiveness in pure quartz media. Detailed experiments unraveled that improved recovery factor by magnetic treatment stem from both mitigated swelling and altered magnetic properties at clay surface; introducing 30% clay to porous medium decreased the recovery by 32% compared to pure quartz sand. Heating the clay to around 1000 °C to reduce its swelling property improved the recovery by only 16%, suggesting magnetic treatment is not solely attributed to clay swelling mitigation. Treating ferromagnetic films at clay surface with HCl to produce non-magnetic FeCl₃ resulted in a high recovery factor, similar to the clay-free medium. Moreover, it was determined that a magnetic field intensity of 43760–51740 A/m is optimal for fluid displacement in clayey media. Notably, the intensity of 47760 A/m increased recovery to 84.5% in a 30% clay medium, compared to 49.7% without treatment. Interestingly, it was observed that the maximum flow rate was associated with zero potential difference across the medium, providing a faster method to determine the optimum magnetic field intensity. Lastly, the concept of ‘Magnetic memory’ was investigated, referring to the persistence of magnetic field's influence after its removal. Our findings indicated that pressure build-up time stability lasted 10 days post-treatment, after which water behavior reverts, and clay swelling resumes. This insight into the temporal dynamics of magnetic field application provides a deeper understanding of its long-term impacts on fluid flow in clayey reservoirs.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 462-471"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000358/pdfft?md5=9de84d2e194b857775d50730214c4695&pid=1-s2.0-S2096249524000358-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140401132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Harnessing deep transient testing for reservoir characterization and CO2 emission reduction in challenging geological settings","authors":"","doi":"10.1016/j.ptlrs.2024.01.014","DOIUrl":"10.1016/j.ptlrs.2024.01.014","url":null,"abstract":"<div><p>This paper provides a comprehensive overview of Deep Transient Testing (DTT), a cutting-edge technique for reservoir characterization that has revolutionized the oil and gas industry. The main aim of DTT is to characterize the reservoir with a deeper radius of investigation. The optimization of the radius of investigation with the DTT approach is studied in detail. Reveal is a commercial numerical simulation application used to simulate the DTT process and evaluate the pressure wave analysis in the porous media. The main aim of the simulation is to understand the impact of the reservoir quality on the pressure response and use it to address the noise-to-pule ratio, which is a determinantal parameter in testing duration. The tested wells with the DTT tool show that measured well productivity can deliver the minimum commercial rate. The has been delivered within 2 days compared to the potential test time of 21 days which saved the 19 rig days and contributed to CO2 emission reduction of (gas flaring 1340 + rig emission 600) 1940 Metric tons equivalent to 421 cars emission in a year. However, DTT also presents certain limitations, such as the requirement for specialized equipment and expertise, as well as the potential for formation damage during testing. This study provides a detailed description of the DTT technique, encompassing its history, theory, and practical applications. Furthermore, it discusses the benefits and limitations of DTT and presents case studies to illustrate its effectiveness across various reservoir types. Overall, this study serves as a valuable resource for reservoir engineers, geologists, and other professionals involved in the exploration and production of oil and gas.</p></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 3","pages":"Pages 380-392"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2096249524000140/pdfft?md5=38d9766f99f359d5eb4728a8d7041478&pid=1-s2.0-S2096249524000140-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140523246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of petrophysical properties of synthetic carbonate plugs: Adding a novel 3D printing approach to control pore networks","authors":"Jhonatan Jair Arismendi Florez,&nbsp;Carina Ulsen,&nbsp;Jean Vicente Ferrari","doi":"10.1016/j.ptlrs.2024.06.006","DOIUrl":"10.1016/j.ptlrs.2024.06.006","url":null,"abstract":"<div><div>The physical and chemical properties of rocks play a crucial role in understanding fluid-solid flow behavior at the pore level. Thus, studying pore space characteristics is important in evaluating and determining petrophysical properties of various rock types, including synthetic rocks, which can be designed to mimic natural rocks. This study investigates the petrophysical properties of synthetic carbonate plugs by using a new approach that correlates the base material and a 3D printing solution with porosity and permeability. The research shows that with precise particle size and morphology, pure mineral materials such as calcite, dolomite, quartz and a non-structural Portland cement may produce a controlled rock matrix. The synthetic plugs developed in this study exhibit controlled macro, meso, and micro porosities, including fractures and vuggys, by the solubilization of materials with controlled morphology by 3D printing, which provides valuable information on regulating pore space in synthetic carbonate rocks.</div></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 4","pages":"Pages 514-540"},"PeriodicalIF":0.0,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141415765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case studies and operation features of transient multiphase flow in low-flow wells with multistage fracturing and extended horizontal wellbore operated with ESP in PSA mode","authors":"T.S. Yushchenko,&nbsp;E.V. Demin,&nbsp;V.A. Ivanov,&nbsp;R.A. Khabibullin,&nbsp;A.V. Volkov","doi":"10.1016/j.ptlrs.2024.06.005","DOIUrl":"10.1016/j.ptlrs.2024.06.005","url":null,"abstract":"<div><div>The article is dedicated to the analysis and modeling of the operation modes of low-flow wells with extended horizontal wellbore (HW) and multi-stage hydraulic fracturing (MHF) during artificial lift with an electric submersible pump (ESP). A comprehensive analysis of the operation modes of Bazhenov formation wells with HW and MHF, working with ESP, has been conducted. Complications in the operation of ESP in such wells, related to proppant carryover, constant productivity decline, and gas factor growth, are shown, and operational data of various types of ESP in wells with complex construction are provided. One of the main parts of the manuscript is the new methodology for creating a model of multiphase transient flow in a well with ESP operating in periodic short-term activation (PSA) mode using specialized software. Various approaches for numerical modeling of transient multiphase flows in a well with ESP and a bottomhole separator were used to accurately describe the physical processes. Difficulties that may arise during well operation were demonstrated through the analysis of field data and numerical modeling results. The work includes modeling of complications in HW due to proppant carryover from MHF fractures, resulting in flow blockage in the well. The article demonstrates the process of tuning transient operation modes of a well with ESP in PSA mode using specialized software based on real field data (multiphase flowmeter, pressure gauges, etc.), taking into account the well construction, ESP characteristics, additional equipment (valves, separator, etc.), and reservoir parameters. The model was tuned to actual data, and possible ways of optimizing the operation mode were shown. In addition, the work provides an analysis of the sensitivity of fluid properties and well parameters to non-stationary flow in the well.</div></div>","PeriodicalId":19756,"journal":{"name":"Petroleum Research","volume":"9 4","pages":"Pages 657-672"},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141390513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}