Sedimentary facies modeling is a critical approach for understanding geological phenomena,yet the strong heterogeneity of reservoir systems poses a serious challenge for their refined characterization.In this study,we...Sedimentary facies modeling is a critical approach for understanding geological phenomena,yet the strong heterogeneity of reservoir systems poses a serious challenge for their refined characterization.In this study,we innovatively propose an interpretable attention-guided generative adversarial network framework with dual-domain learning,which achieves precise sedimentary facies modeling under the constraints of well facies and soft probability data.Specifically,we first effectively extract and preserve prior information of sedimentary facies models from both spatial and frequency domain perspectives.Then,during simulation,to enhance the capability of the network model for finely characterizing complex heterogeneous models,cross-spatial attention mechanisms are designed to effectively capture short-range and long-range dependencies between multi-scale pattern features.Additionally,through systematic feature map visualization analysis,we elucidate the processes of conditional fitting and complex sedimentary facies model reconstruction,intuitively demonstrating the functional mechanisms of each module.Finally,systematic experiments are conducted on multiple datasets to validate the effectiveness of the proposed method.The results demonstrate that the generated sedimentary facies models exhibit high consistency with training datasets in terms of visual realism and statistical indicators.Quantitative comparisons reveal remarkable performance of the method,achieving low Wasserstein distance(0.09),Kernel Inception Distance(0.0017)and Kernel Maximum Mean Discrepancy(0.21).These findings further confirm the high realism of the generated realizations regarding pattern features.This study offers a reliable and practical method for geological reservoir modeling,thereby advancing quantitative,precise geological research with broad application prospects.展开更多
The laminar sedimentary structures of saline lacustrine mixed rocks affect both organic matter enrichment and reservoir storage performance.However,due to the small-scale nature of laminae,large-scale identification u...The laminar sedimentary structures of saline lacustrine mixed rocks affect both organic matter enrichment and reservoir storage performance.However,due to the small-scale nature of laminae,large-scale identification using well-logging data during reservoir exploration and development remains challenging.It is necessary to introduce a research method to identify and characterize the development of different types of laminae.Based on analyses of typical cores,XRD data,and welllogging curves from the upper member of the Xiaganchaigou Formation in the Yingxi area,five main types of laminae and six lamina combinations were classified.A Transformer-based intelligent recognition method was then applied to identify these lamina combinations from well-log data,with the Random Forest algorithm used as a comparative benchmark.Verification results show that the Transformer model achieves a higher total accuracy of 84%in lamina combination recognition.This study proposes a new approach for the conventional well-log characterization of laminae,in which the classification is established from the perspective of laminae genesis.It reflects the development patterns of lamina combinations driven by paleoenvironmental changes,and selects an appropriate intelligent recognition method to address the challenges in well-log characterization of such reservoirs.In terms of engineering applications,this study can accurately indicate the positions of high-quality reservoirs within sedimentary cycles during field development.It provides a sedimentary facies-controlled basis for the three-dimensional characterization of reservoir quality,thereby offering a valuable reference for the exploration and development of reservoirs formed under similar sedimentary conditions.展开更多
Al-Si coated ultra-high strength steel(UHSS)has been commonly applied in hot stamping process.The influence of austenitizing temperature on microstructure of Al-Si coating of UHSS during hot stamping process and its...Al-Si coated ultra-high strength steel(UHSS)has been commonly applied in hot stamping process.The influence of austenitizing temperature on microstructure of Al-Si coating of UHSS during hot stamping process and its tribological behavior against H13 steel under elevated temperature were simulatively investigated.The austenitizing temperature of Al-Si coated UHSS and its microstructual evolution were confirmed and analyzed by differential scanning calorimetry and scanning electron microscopy.A novel approach to tribological testing by replicating hot stamping process temperature history was presented.Results show that the hard and stable phases Fe_2Al_5+FeAl_2 formed on Al-Si coating surface after exposure to 930°C for 5 min,which was found to be correlated to the tribological behavior of coating.The friction coefficient of coated steel was more stable and higher than that of uncoated one.The main wear mechanism of Al-Si coated UHSS was adhesion wear,while abrasive wear was dominant for the uncoated UHSS.展开更多
In this work,the serpentine powders were sintered to make the serpentine-reinforced Al-matrix composites,and the microstructures of which were characterized by differential scanning calorimetry,thermal gravimetric ana...In this work,the serpentine powders were sintered to make the serpentine-reinforced Al-matrix composites,and the microstructures of which were characterized by differential scanning calorimetry,thermal gravimetric analyzer,and X-ray diffractometer.Scanning electron microscopy equipped with energy dispersive spectroscopy.Results show that the sintered serpentine powders were deeply absorbed on the worn surface and embedded in the furrows and scratches of the matrix,forming a self-repairing surface layer which reduces the friction coefficient.The surface layer coated by serpentine was compact,dense,and uniform with the friction time prolonged,compensating the worn loss and increasing the matrix mass.展开更多
Characterizing the sedimentary architecture of successions of shallow-water deltas fed by braided rivers is crucial for the prediction of sandbody development in potential field.However,the complex distribution and di...Characterizing the sedimentary architecture of successions of shallow-water deltas fed by braided rivers is crucial for the prediction of sandbody development in potential field.However,the complex distribution and diverse sedimentary characteristics of these deltas have led to insufficient insight into the controlling factors for different types.Based on high-resolution seismic data and well-logging data from the P Oilfield in the Bohai Bay Basin,two zones(Ⅰ1 and Ⅲ2)within the Neogene upper member of Guantao Formation were selected.Utilizing palynological analysis,elemental geochemical analysis,and frequency-division seismic-attribute fusion technology based on an ensemble-machine-learning algorithm,paleoclimate analysis and detailed architectural characterization of the studied stratigraphic interval were conducted.The findings indicate that:(1)Two palynological assemblages were identified in the upper member of Guantao Formation:assemblageⅠsuggests a subtropical-temperate monsoon climate,while assemblageⅡindicates a continental semi-arid climate.(2)ZoneⅠ1 represents a lobate shallow-water braided-river delta,whereas zone Ⅲ2 represents a lobate shallow-water braided-river delta with bar-finger.(3)Stable discharge conditions and a high bedload fraction under a subtropical-temperate monsoon climate facilitate the formation of the lobate shallow water delta.A low bedload fraction provides a favorable condition for the development of barfinger,but flood events under a continental semi-arid climate enhance channel-mouth deposition driving the formation of the lobate delta with bar-finger.展开更多
The Lower Ganchaigou Formation in the Yingxi area of the Qaidam Basin is a typical lacustrine mixed rock reservoir in western China.It is characterized by strong interlayer heterogeneity,development of diverse lithofa...The Lower Ganchaigou Formation in the Yingxi area of the Qaidam Basin is a typical lacustrine mixed rock reservoir in western China.It is characterized by strong interlayer heterogeneity,development of diverse lithofacies types,and complex response features in logging curves.These complexities make lithofacies identification of the Ganchaigou Formation particularly challenging for non-coring wells,demanding a more efficient and accurate approach.Based on lithology and structural patterns,a lithofacies classification scheme was established.Three intelligent logging identification methods based on improved long short-term memory(LSTM)networks were constructed for lithofacies identification.The accuracy of these methods was evaluated,and the most suitable intelligent logging identification method for the reservoir lithofacies in the Yingxi area was selected.In the Upper Xiaganchaigou Formation(E32 section)of the Yingxi area,a total of eight lithofacies types were identified:laminated lime-dolostone,stratified lime-dolostone,laminated dolostonelime,stratified dolostone-lime,laminated lime-dolomitic shale,massive mudstone,sandstone,and gypsum.The overall recognition accuracies of the LSTM,Bi-LSTM,and Attention-based Bi-LSTM intelligent identification models are 81%,85%,and 87%,respectively.The overall recognition accuracies of the three intelligent algorithms are relatively high,with the Attention-based Bi-LSTM model achieving the highest accuracy.This model demonstrates superior applicability for intelligent lithofacies identification in lacustrine mixed rock reservoirs,particularly those dominated by carbonates in the Yingxi area.It effectively interprets the lithofacies types of non-coring wells in the study area and provides a valuable reference for interpreting lithofacies logs in similar depositional environments.展开更多
In offshore fields with limited well data,intricate geological configurations,and high reservoir heterogeneity,the accurate prediction of sand body distribution and characterization of sedimentary architecture pose si...In offshore fields with limited well data,intricate geological configurations,and high reservoir heterogeneity,the accurate prediction of sand body distribution and characterization of sedimentary architecture pose significant challenges due to inherent geological uncertainties and data limitations.This study employs a comprehensive approach integrating three key methods to enhance prediction accuracy:(i)fusion of spectral-decomposed seismic attributes,(ii)seismic attribute fusion of target and neighboring zones,and(iii)colored seismic inversion.The first method leverages seismic information across various frequencies,yielding reliable results for sand bodies of different thicknesses.The second method mitigates the impact of seismic responses from adjacent zones on sand body predictions,making it particularly suitable for target intervals where neighboring zones significantly influence the seismic response.The third one,colored seismic inversion enhances the prediction of vertical distribution and the stacking relationships of sand bodies.These methods have been applied in an oilfield in the Pearl River Mouth Basin,southern China.Consequently,the sedimentary architecture of a braided river delta reservoir is successfully characterized,leading to the identification of four distributary channels within a depositional Zone 1 of the Zhujiang Formation.Additionally,a comprehensive workflow integrating well logs,seismic data,and depositional models significantly improves predictions of sand body distribution and sedimentary architecture in complex geological settings,providing critical geological insights for optimizing subsequent oilfield development strategies.展开更多
基金supported by National Science and Technology Major Project"CO2 Flooding for Significantly Enhancing Recovery Rate and Long-Term Sequestration Technology"(No.2024ZD1406601)National Natural Science Foundation of China(Nos.42272186,42472179,42302128,42202109)+1 种基金Frontier Interdisciplinary Exploration Research Program of China University of Petroleum,Beijing(No.2462024XKQY003)Science Foundation of China University of Petroleum(Beijing)(Nos.2462023BJRC024,and 2462023YJRC039)。
摘要Sedimentary facies modeling is a critical approach for understanding geological phenomena,yet the strong heterogeneity of reservoir systems poses a serious challenge for their refined characterization.In this study,we innovatively propose an interpretable attention-guided generative adversarial network framework with dual-domain learning,which achieves precise sedimentary facies modeling under the constraints of well facies and soft probability data.Specifically,we first effectively extract and preserve prior information of sedimentary facies models from both spatial and frequency domain perspectives.Then,during simulation,to enhance the capability of the network model for finely characterizing complex heterogeneous models,cross-spatial attention mechanisms are designed to effectively capture short-range and long-range dependencies between multi-scale pattern features.Additionally,through systematic feature map visualization analysis,we elucidate the processes of conditional fitting and complex sedimentary facies model reconstruction,intuitively demonstrating the functional mechanisms of each module.Finally,systematic experiments are conducted on multiple datasets to validate the effectiveness of the proposed method.The results demonstrate that the generated sedimentary facies models exhibit high consistency with training datasets in terms of visual realism and statistical indicators.Quantitative comparisons reveal remarkable performance of the method,achieving low Wasserstein distance(0.09),Kernel Inception Distance(0.0017)and Kernel Maximum Mean Discrepancy(0.21).These findings further confirm the high realism of the generated realizations regarding pattern features.This study offers a reliable and practical method for geological reservoir modeling,thereby advancing quantitative,precise geological research with broad application prospects.
基金financially supported by National Major Science and Technology Projects of China(No.2024ZD1406601)National Natural Science Foundation of China(Nos.42272186,42302128,42472179,42202109)。
摘要The laminar sedimentary structures of saline lacustrine mixed rocks affect both organic matter enrichment and reservoir storage performance.However,due to the small-scale nature of laminae,large-scale identification using well-logging data during reservoir exploration and development remains challenging.It is necessary to introduce a research method to identify and characterize the development of different types of laminae.Based on analyses of typical cores,XRD data,and welllogging curves from the upper member of the Xiaganchaigou Formation in the Yingxi area,five main types of laminae and six lamina combinations were classified.A Transformer-based intelligent recognition method was then applied to identify these lamina combinations from well-log data,with the Random Forest algorithm used as a comparative benchmark.Verification results show that the Transformer model achieves a higher total accuracy of 84%in lamina combination recognition.This study proposes a new approach for the conventional well-log characterization of laminae,in which the classification is established from the perspective of laminae genesis.It reflects the development patterns of lamina combinations driven by paleoenvironmental changes,and selects an appropriate intelligent recognition method to address the challenges in well-log characterization of such reservoirs.In terms of engineering applications,this study can accurately indicate the positions of high-quality reservoirs within sedimentary cycles during field development.It provides a sedimentary facies-controlled basis for the three-dimensional characterization of reservoir quality,thereby offering a valuable reference for the exploration and development of reservoirs formed under similar sedimentary conditions.
基金the financial support from National Natural Science Foundation of China(Grand No.51475280)
摘要Al-Si coated ultra-high strength steel(UHSS)has been commonly applied in hot stamping process.The influence of austenitizing temperature on microstructure of Al-Si coating of UHSS during hot stamping process and its tribological behavior against H13 steel under elevated temperature were simulatively investigated.The austenitizing temperature of Al-Si coated UHSS and its microstructual evolution were confirmed and analyzed by differential scanning calorimetry and scanning electron microscopy.A novel approach to tribological testing by replicating hot stamping process temperature history was presented.Results show that the hard and stable phases Fe_2Al_5+FeAl_2 formed on Al-Si coating surface after exposure to 930°C for 5 min,which was found to be correlated to the tribological behavior of coating.The friction coefficient of coated steel was more stable and higher than that of uncoated one.The main wear mechanism of Al-Si coated UHSS was adhesion wear,while abrasive wear was dominant for the uncoated UHSS.
基金supported by the National Natural Science Foundation of China (Grant Nos. 50975166 and 51475280)the Excellent Engineer Training Program (Metallic material engineering of Shanghai University) of Ministry of Education, China
摘要In this work,the serpentine powders were sintered to make the serpentine-reinforced Al-matrix composites,and the microstructures of which were characterized by differential scanning calorimetry,thermal gravimetric analyzer,and X-ray diffractometer.Scanning electron microscopy equipped with energy dispersive spectroscopy.Results show that the sintered serpentine powders were deeply absorbed on the worn surface and embedded in the furrows and scratches of the matrix,forming a self-repairing surface layer which reduces the friction coefficient.The surface layer coated by serpentine was compact,dense,and uniform with the friction time prolonged,compensating the worn loss and increasing the matrix mass.
基金supported by the National Natural Science Foundation Project of China(Nos.42272186,41872107,42202109,42472179,42302128)the National Major Science and Technology Project(Nos.2025ZD1404304,2024ZD1406601)Yong Elite Scientist Sponsorship Program by Bast of China(No.BYESS2023460)。
摘要Characterizing the sedimentary architecture of successions of shallow-water deltas fed by braided rivers is crucial for the prediction of sandbody development in potential field.However,the complex distribution and diverse sedimentary characteristics of these deltas have led to insufficient insight into the controlling factors for different types.Based on high-resolution seismic data and well-logging data from the P Oilfield in the Bohai Bay Basin,two zones(Ⅰ1 and Ⅲ2)within the Neogene upper member of Guantao Formation were selected.Utilizing palynological analysis,elemental geochemical analysis,and frequency-division seismic-attribute fusion technology based on an ensemble-machine-learning algorithm,paleoclimate analysis and detailed architectural characterization of the studied stratigraphic interval were conducted.The findings indicate that:(1)Two palynological assemblages were identified in the upper member of Guantao Formation:assemblageⅠsuggests a subtropical-temperate monsoon climate,while assemblageⅡindicates a continental semi-arid climate.(2)ZoneⅠ1 represents a lobate shallow-water braided-river delta,whereas zone Ⅲ2 represents a lobate shallow-water braided-river delta with bar-finger.(3)Stable discharge conditions and a high bedload fraction under a subtropical-temperate monsoon climate facilitate the formation of the lobate shallow water delta.A low bedload fraction provides a favorable condition for the development of barfinger,but flood events under a continental semi-arid climate enhance channel-mouth deposition driving the formation of the lobate delta with bar-finger.
基金supported by the the National Natural Science Foundation of China(No.42272186,42302128,42202109 and 42472179)
摘要The Lower Ganchaigou Formation in the Yingxi area of the Qaidam Basin is a typical lacustrine mixed rock reservoir in western China.It is characterized by strong interlayer heterogeneity,development of diverse lithofacies types,and complex response features in logging curves.These complexities make lithofacies identification of the Ganchaigou Formation particularly challenging for non-coring wells,demanding a more efficient and accurate approach.Based on lithology and structural patterns,a lithofacies classification scheme was established.Three intelligent logging identification methods based on improved long short-term memory(LSTM)networks were constructed for lithofacies identification.The accuracy of these methods was evaluated,and the most suitable intelligent logging identification method for the reservoir lithofacies in the Yingxi area was selected.In the Upper Xiaganchaigou Formation(E32 section)of the Yingxi area,a total of eight lithofacies types were identified:laminated lime-dolostone,stratified lime-dolostone,laminated dolostonelime,stratified dolostone-lime,laminated lime-dolomitic shale,massive mudstone,sandstone,and gypsum.The overall recognition accuracies of the LSTM,Bi-LSTM,and Attention-based Bi-LSTM intelligent identification models are 81%,85%,and 87%,respectively.The overall recognition accuracies of the three intelligent algorithms are relatively high,with the Attention-based Bi-LSTM model achieving the highest accuracy.This model demonstrates superior applicability for intelligent lithofacies identification in lacustrine mixed rock reservoirs,particularly those dominated by carbonates in the Yingxi area.It effectively interprets the lithofacies types of non-coring wells in the study area and provides a valuable reference for interpreting lithofacies logs in similar depositional environments.
基金supported by National Natural Science Foundation Project of China(Nos.42272186,42302128,42202109,42472179)the Cooperation Project of the PetroChina Corporation(ZLZX2020-02)Young Elite Scientist Sponsorship Program by Bast of China(BYESS2023460)。
摘要In offshore fields with limited well data,intricate geological configurations,and high reservoir heterogeneity,the accurate prediction of sand body distribution and characterization of sedimentary architecture pose significant challenges due to inherent geological uncertainties and data limitations.This study employs a comprehensive approach integrating three key methods to enhance prediction accuracy:(i)fusion of spectral-decomposed seismic attributes,(ii)seismic attribute fusion of target and neighboring zones,and(iii)colored seismic inversion.The first method leverages seismic information across various frequencies,yielding reliable results for sand bodies of different thicknesses.The second method mitigates the impact of seismic responses from adjacent zones on sand body predictions,making it particularly suitable for target intervals where neighboring zones significantly influence the seismic response.The third one,colored seismic inversion enhances the prediction of vertical distribution and the stacking relationships of sand bodies.These methods have been applied in an oilfield in the Pearl River Mouth Basin,southern China.Consequently,the sedimentary architecture of a braided river delta reservoir is successfully characterized,leading to the identification of four distributary channels within a depositional Zone 1 of the Zhujiang Formation.Additionally,a comprehensive workflow integrating well logs,seismic data,and depositional models significantly improves predictions of sand body distribution and sedimentary architecture in complex geological settings,providing critical geological insights for optimizing subsequent oilfield development strategies.