{"title":"Insights into the role of tectonic extension and compression vs. subduction erosion in the tectonics of forearcs: Examples from the Japan Trench and the Middle America Trench","authors":"Paola Vannucchi , Jason P. Morgan","doi":"10.1016/j.earscirev.2024.104902","DOIUrl":"10.1016/j.earscirev.2024.104902","url":null,"abstract":"<div><p>The forearc region remains key in understanding the dynamics of convergent plate tectonics. This study focuses on the mechanisms governing tectonic processes within the overriding plate forearc which spans from the trench to the volcanic arc at two key and relatively well studied regions: the Japan Trench and the Middle America Trench offshore SE Costa Rica. We address the questions that have arisen concerning material input into the plate boundary, whether by subduction, accretionary prism formation, or tectonic erosion. In the Japan Trench case study, while tectonic accretion occurs near the trench axis, significant forearc subsidence suggests net material removal, possibly through tectonic erosion that has transferred material to the subducting slab. Debate surrounds the mechanism driving forearc subsidence, with recent studies proposing extensional tectonism as a possible mechanism to exclude subduction erosion. However, seismic evidence challenges this hypothesis, as normal faults indicative of forearc extension are not prominent. Moreover, a quantitative mass-balance analysis fails for the forearc if extensional tectonics rather than tectonic erosion is assumed to have predominantly shaped the margin. The spatio-temporal progression of subsidence across the forearc is further explored; this indicates that peak subduction erosion has occurred beneath the lower slope. The Middle America Trench in SE Costa Rica has also been extensively studied with several drilling expeditions, with particular focus on the area where the aseismic Cocos Ridge is subducting beneath the Caribbean plate. Here the subduction of topographic relief has been traditionally viewed as a process that enhances subduction erosion. Recent studies have challenged this perspective, suggesting instead that subducting topography might lead to net accretion to the margin through various mechanisms. Ocean drilling expeditions provide valuable data on sedimentary successions and forearc tectonic evolution. These drilling data have been not always used to the best of their capacity, which has led to significant discrepancies between drilling-based inferences and seismic interpretations, in particular regarding the presence and nature of unconformities within the forearc sediments. Borehole observations strongly favor the inference that inboard the Cocos Ridge a large amount of subsidence has occurred, linked to recent subduction erosion beneath this forearc.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104902"},"PeriodicalIF":10.8,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0012825224002290/pdfft?md5=00011b9b238a92bb19e33741e5e73707&pid=1-s2.0-S0012825224002290-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142012789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Geological Evolution of the Karakoram Terrane since Neoproterozoic","authors":"Shailendra Pundir, Vikas Adlakha","doi":"10.1016/j.earscirev.2024.104890","DOIUrl":"10.1016/j.earscirev.2024.104890","url":null,"abstract":"<div><p>The Karakoram Terrane (KT) in the western margin of the Himalayan-Tibetan orogen preserves the record of the Tethyan oceanic lithospheric subduction beneath the Asian Plate and metamorphism linked to the subduction of the Indian slab and the India-Asia collision. This terrane is also significant for understanding the changes in tectonics over time in the continent-continent collision zones related to mantle dynamics, slab underthrusting, or large-scale strike-slip faults. Despite a long geological research history over the past 140 years, this terrane's magmatic, petrogenetic, deformation, and uplift history remains enigmatic. This is mainly because of non-consensus over the distribution, source, and processes for the emplacement of variably occurring I-and S-type granitoids and changing tectonic processes through time. Thus, to resolve these issues, this paper reviews the KT's magmatic, deformation, and uplift history. Apart from its Neoproterozoic basement, two main stages of Andean-type magmatism have been identified in the KT. Stage 1 happened during ∼160-100 Ma, forming hornblende (Hbl)-biotite (Bt)-bearing and Bt-bearing granitoids. The field evidence, hybrid isotope signatures, and thermodynamic whole-rock major element modeling show that the formation of these granitoids involves assimilation with upper crustal rocks. The Stage 2 Hbl-Bt bearing Pangong Transpression Zone (PTZ) granitoids in the eastern KT were formed during ∼83-56 Ma; they show juvenile isotopic signatures and, thus, their origin from the mantle. The major element thermodynamic modeling of these granitoids suggests that these rocks were formed due to fractional crystallization. Our compilation and analysis of geochemical, isotopic, and geochemical modeling suggest that these granitoids belong to the Ladakh magmatic arc rather than the Karakoram Batholith granitoids of the KT, contrary to earlier beliefs. The origin of Eocene-Oligocene leucogranites of the KT remains controversial with the variable inferred processes of their origin, like water-flux melting of granitoids, dehydration melting of metapelites, and slab-breakoff, shearing or compression-induced partial melt generation. This study assesses these scenarios by compiling geochronological, geochemical, and isotopic data to understand the role of these processes in partial melt generation over spatial and temporal scales. Our assessment suggests that the monzogranites and hbl-bearing leucogranites are generated as a result of slab-breakoff and KF shearing-induced melting of the existing igneous sources, while the two-mica±grt leucogranites are sourced from the melting of supracrustal metapelitic rocks due to crustal thickening. This paper provides the compilation of cooling rates from all the published mid-to-low temperature thermochronometric ages to assess the different phases of the uplift of the KT on spatial and temporal scales. Our compilation suggests that the KT was uplifted mainly in three phases: (","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104890"},"PeriodicalIF":10.8,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142012776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David J. Sanderson , David C.P. Peacock , Casey W. Nixon
{"title":"Fracture sets and sequencing","authors":"David J. Sanderson , David C.P. Peacock , Casey W. Nixon","doi":"10.1016/j.earscirev.2024.104888","DOIUrl":"10.1016/j.earscirev.2024.104888","url":null,"abstract":"<div><p>Fractures in a network are commonly divided into “sets” to facilitate their description and analysis. Sets can be based on many different criteria that include the type, geometry, size, spatial distribution, relative age and the kinematics of the fractures. Orientation is the most widely used criterion, but alone may be inadequate to define a fracture set, since fractures of different type, origin and age may share similar orientations. The criteria used should be clearly stated, with quantitative measures where possible, to allow unambiguous and reproducible allocation of fractures to sets, with assessment of the variability or uncertainty involved. Identifying a consistent sequence of development is a key aspect of fracture set determination. This can be quantified by considering the abutting and cross-cutting relationships between different fracture sets using a sequence matrix.</p><p>Examples of networks of joints and faults are presented to illustrate different aspects of set definition and network characterization, emphasising the need for criteria that are appropriate for the type of fracture network, available data and the hypotheses to be tested. We discuss how the “deconstruction” of a fracture network into sets is important for fracture network characterization, and how these sets may then be used to “reconstruct” a fracture network to produce models suitable for studies of tectonics, mechanics and fluid flow.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104888"},"PeriodicalIF":10.8,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141990338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dongwei Gui , Qi Liu , Jaime Martínez-Valderrama , Sameh Kotb Abd-Elmabod , Zeeshan Ahmed , Zhiwei Xu , Jiaqiang Lei
{"title":"Desertification baseline: A bottleneck for addressing desertification","authors":"Dongwei Gui , Qi Liu , Jaime Martínez-Valderrama , Sameh Kotb Abd-Elmabod , Zeeshan Ahmed , Zhiwei Xu , Jiaqiang Lei","doi":"10.1016/j.earscirev.2024.104892","DOIUrl":"10.1016/j.earscirev.2024.104892","url":null,"abstract":"<div><p>The desertification baseline is the standard to measure the severity of desertification and is imperative to achieve the target of land degradation neutrality of UN Sustainable Development Goal (SDG) 15.3. However, desertification baselines are fragmented because of various modeling approaches and incompatible thresholds of indicators, leading to the evaluation results of desertification shrouded in controversy. In this review, we have examined the current status of the desertification baseline and explored its current problems and potential directions. Potential natural conditions, the theoretical conditions that would occur under existing environmental conditions without active human intervention, can standardize the evaluation of desertification and restoration in drylands to make assessments more compatible across and within regions. The results of our perspective will raise attention to desertification and put forward the establishment of a robust and unified desertification baseline to help achieve land degradation neutrality and conserve the multiple environmental, economic, and social benefits drylands provide.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104892"},"PeriodicalIF":10.8,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142039753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Precipitation is the main control on the global distribution of soil clay minerals","authors":"Hengzhi Lyu, Huayu Lu","doi":"10.1016/j.earscirev.2024.104891","DOIUrl":"10.1016/j.earscirev.2024.104891","url":null,"abstract":"<div><p>The global distribution of clay minerals is intricately linked with climatic conditions and bedrock composition, which interact to control the weathering intensity of silicate and other minerals. However, the quantitative relationship between clay minerals and climate is not well understood, partly due to the lack of quantitative assessments of the role of the various factors responsible for clay mineral formation. Here we examine the quantitative relationship between soil clay minerals and climatic factors on the global scale, by extrapolating clay mineral abundances to a large scale. We found that mean annual precipitation (MAP) is the first order control on the global clay mineral distribution, while mean annual temperature (MAT), elevation, slope, lithology, upland hillslope soil thickness (UHST), and upland hillslope regolith thickness (UHRT) have secondary roles or localized impacts on clay mineral distributions. We found that precipitation thresholds exist in weathering intensity and clay mineral formation: (1) Illite decreases monotonically and kaolinite increases monotonically with increasing MAP below the threshold of 1800–2000 mm, whereas gibbsite increases monotonically with increasing MAP below the threshold of 2200–2400 mm. (2) Smectite and Fe oxides increase with increasing MAP below the threshold of 600–800 mm, and then decrease with increasing MAP between 600 and 800 mm and 1800–2000 mm. (3) All clay minerals are insensitive to extremely high MAP, above 1800–2000 mm. We suggest that paleoprecipitation can be semi-quantitatively reconstructed based on variations in the relative contents of clay minerals, which can be used as a proxy indicator of wet and dry variations for paleoclimate studies.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104891"},"PeriodicalIF":10.8,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141979285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lei Lin , Zhi Zhong , Chenglong Li , Andrew Gorman , Hao Wei , Yanbin Kuang , Shiqi Wen , Zhongxian Cai , Fang Hao
{"title":"Machine learning for subsurface geological feature identification from seismic data: Methods, datasets, challenges, and opportunities","authors":"Lei Lin , Zhi Zhong , Chenglong Li , Andrew Gorman , Hao Wei , Yanbin Kuang , Shiqi Wen , Zhongxian Cai , Fang Hao","doi":"10.1016/j.earscirev.2024.104887","DOIUrl":"10.1016/j.earscirev.2024.104887","url":null,"abstract":"<div><p>Identification of geological features from seismic data such as faults, salt bodies, and channels, is essential for studies of the shallow Earth, natural disaster forecasting and evaluation, carbon capture and storage, hydrogen storage, geothermal energy development, and traditional resource exploration. However, manual seismic interpretation is distinctly subjective and labor-intensive. With the advent and rise of 3D surveys, the size of seismic data has increased dramatically, making purely manual interpretation impractical. Since 1989, a large number of machine learning-based methods for identifying geological features have been proposed to address these challenges. To date, these methods have not been reasonably synthesized. Motivated by a progressive increase in applications, this review presents an overview of advances in the utilization of machine learning to identify geological features from seismic data. First, we classify these methods from five different perspectives. Second, we provide a comprehensive overview of 241 publications related to seismic geological feature identification and offer a detailed analysis of the development of these methods categorized by geological feature type. Third, 20 field and 12 synthetic seismic datasets, which are publicly available and relevant to the identification of faults, salt bodies, channels, caves, and horizons, are cataloged. Fourth, we discuss the issue of false positive identification caused by the limited geological features in the training dataset. To address the problems of false positives and insufficient labeled training datasets, we propose a simulation framework for generating 3D synthetic seismic data and corresponding geological labels that include a rich variety of geological features. To the best of our knowledge, this is the synthetic seismic dataset that contains the richest geological features. Finally, we discuss in depth the current challenges and future opportunities to inspire further relevant research.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104887"},"PeriodicalIF":10.8,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141964222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiamin Zhou , Longyi Shao , Timothy P. Jones , Yangyang Huang , Mengran Chen , Haihai Hou , Jing Lu , Jason Hilton
{"title":"Mechanisms of inertinite enrichment in Jurassic coals: Insights from a Big Data-driven review","authors":"Jiamin Zhou , Longyi Shao , Timothy P. Jones , Yangyang Huang , Mengran Chen , Haihai Hou , Jing Lu , Jason Hilton","doi":"10.1016/j.earscirev.2024.104889","DOIUrl":"10.1016/j.earscirev.2024.104889","url":null,"abstract":"<div><p>Big Data-driven research is thriving in the geosciences, with initiatives such as The Deep-Time Digital Earth (DDE) program (<span><span>https://deep-time.org/</span><svg><path></path></svg></span>), which is a “big science program” by the International Union of Geological Sciences (IUGS). Northern and northwestern Chinese environments produced a significant number of typically inertinite-rich coals during the Jurassic, which have been extensively researched and represent a high-quality subject for Big Data-driven studies. Inertinite in coals are widely accepted and applied as direct evidence of palaeowildfire with important palaeoclimatic significance, but the enrichment mechanism of inertinite in Jurassic coals have not yet been comprehensively understood. In this research, Big Data methodology and thinking were used to collect 1298 sources of information with inertinite content, and to reconstruct the palaeogeographic distributions of that inertinite. In addition, >300 datasets on polycyclic aromatic hydrocarbons (PAHs) and inertinite reflectance were collected. Based on these data and in combination with palaeoclimatic databases, two enrichment mechanisms for the high levels of inertinite are proposed. The results show that Jurassic coals in China are significantly enriched in inertinite compared to coals in the rest of the world, with an average inertinite content of 18.9% in the Early Jurassic and up to 36.8% in the Middle Jurassic. Combustion-sourced PAHs are widespread in Jurassic coal seams in different basins and are dominated by 4-ring and 5-ring PAHs. Both coal petrology and PAHs characteristics are indicative of a wildfire origin for inertinite, and the inertinite reflectances suggest that the palaeowildfire types were mainly low-temperature fires. It is proposed that the abundant inertinites in Jurassic coals were formed as the result of the multi-factorial coupling of palaeoflora, palaeoclimates, and palaeoenvironmental evolution. The enrichment models for the inertinite in the Early-Middle Jurassic coals indicate that these inertinites were mainly formed during periods of more obvious seasonal contrasts. Based on analysis from a Big Data review of inertinite concentrations in coals, a quantitative classification criterion is proposed to define those with >30% inertinite as “inertinite-rich coal”, and those with >50% inertinite as “inertinite coal”.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104889"},"PeriodicalIF":10.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142049757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fang Zhang , Haifeng Fan , Hongjie Zhang , Yaowen Wu , Danish Khan , Massam Ali , Hanjie Wen , Fanghui Li , Jiaolong Xiao , Fan Zhang
{"title":"REY-P cycles recorded by the Ediacaran phosphorite on the Yangtze Platform (South China)","authors":"Fang Zhang , Haifeng Fan , Hongjie Zhang , Yaowen Wu , Danish Khan , Massam Ali , Hanjie Wen , Fanghui Li , Jiaolong Xiao , Fan Zhang","doi":"10.1016/j.earscirev.2024.104885","DOIUrl":"10.1016/j.earscirev.2024.104885","url":null,"abstract":"<div><p>Rare earth elements and yttrium (REY) composition of paleo-seawater and redox conditions of localized water masses during deposition are documented by the REY preserved in modern pristine chemical sedimentary phosphorites. However, contrary to modern phosphorites, some older ones (e.g., Cambrian and Proterozoic phosphorites) display anomalous REY patterns that deviate from modern seawater, and limit the use of their parameters (e.g., Ce anomalies) as a reliable proxy for redox conditions in this case. In this work, elements of bulk-rocks and apatite grains, Sr<img>Nd isotopes, and phosphate oxygen isotopes (δ<sup>18</sup>O<sub>P</sub>) from Jingxiang (JX), Yichang (YC), and Xingshen (XS) phosphorites of the Ediacaran Doushantuo Formation in South China were investigated to address this quandary. The REY indexes and patterns of bulk-rocks and apatite, as well as Nd isotopes of bulk-rocks, suggest that the phosphorites deposited in the lower, middle, and upper members of the Ediacaran Doushantuo Formation record the sources of REY as being of terrigenous, mixed, and seawater origins, respectively. During the deposition of the Ediacaran Doushantuo Formation, high δ<sup>18</sup>O<sub>P</sub> values (18.61 ± 1.04) of all bulk-rocks, close to contemporary marine authigenic apatite, indicate that phosphorus has been involved in strong marine bio-cycling, assuming a final terrestrial source. However, REY composition of the seawater column recorded by authigenic apatite in the lower member of Doushantuo Formation exhibited a right-leaning REY pattern, representing a terrestrial REY end-member. The <sup>87</sup>Sr/<sup>86</sup>Sr ratios of bulk-rocks (0.71031 ± 0.00719) and apatite grains (0.71098 ± 0.00099) also remained consistent throughout the Ediacaran Doushantuo Formation, except for the high <sup>87</sup>Sr/<sup>86</sup>Sr values found in bulk-rocks (0.72200 ± 0.00085) and apatite (0.72271 ± 0.00064) in the lower member of JX, which are presumed to result from source rocks with high radioactive Sr. Combined with REY indexes (Ce anomalies, Y/Ho ratios, and the differentiation of REY) and constant <sup>87</sup>Sr/<sup>86</sup>Sr values of apatite, varying REY patterns from the lower to upper members of the Doushantuo Formation indicate that the scavenging rate of terrestrial REY inputs to the ocean by suspended particles (e.g., Fe<img>Mn oxyhydroxides) in the water column is controlled by the degree of seawater oxidation. Our study highlights that REY inputs to seawater could undergo seawater cycling (i.e., the removal of REY by particulates of seawater under oxygen-containing conditions), and only REY that undergo sufficient seawater cycling can reflect the true redox conditions of the water column. Therefore, the sources and cycling of REY in seawater should be carefully identified when applying Ce anomalies and Y/Ho ratios of phosphorites to trace the redox conditions of ancient seawater.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"256 ","pages":"Article 104885"},"PeriodicalIF":10.8,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141934970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianchao Cai, Xinghe Jiao, Han Wang, Wu He, Yuxuan Xia
{"title":"Multiphase fluid-rock interactions and flow behaviors in shale nanopores: A comprehensive review","authors":"Jianchao Cai, Xinghe Jiao, Han Wang, Wu He, Yuxuan Xia","doi":"10.1016/j.earscirev.2024.104884","DOIUrl":"10.1016/j.earscirev.2024.104884","url":null,"abstract":"<div><p>The complicated flow behaviors of multiphase fluids in shale reservoirs are significantly influenced by fluid-fluid and fluid-rock interactions due to the non-negligible intermolecular forces at the nanoscale, which is crucial for the effective development and efficient extraction of shale oil. The complexity of multiphase fluid distribution and flow behaviors in shale reservoirs is further increased by low porosity, low permeability, poor connectivity, high inhomogeneity, and multi-component minerals, making the development process more challenging. Molecular dynamics simulation is widely to precisely capture the intermolecular forces and effectively explain the complex distribution and flow behaviors of these fluids under fluid-fluid and fluid-rock interaction forces. In this review, the characteristics of mineral composition, pore structure, porosity, permeability, and fluid types are first elaborated to illustrate the particularity of shale reservoirs and fluids compared to conventional scale reservoirs. The results show that shale minerals are composed of inorganic and organic matter with extremely low porosity and permeability, and nanoscale pore size, in which the complicated oil-water-CO<sub>2</sub> multiphase fluid types are caused by the primary underground water, fracturing water and injected CO<sub>2</sub>. The research progress of molecular simulation on the fluid-fluid and fluid-rock interaction mechanisms and on multiphase shale fluids flow behaviors are then reviewed in detail. The strong intermolecular interaction forces can result in the different occurrence states of fluids, the fluid-fluid interfacial slip, the fluid-rock boundary slip and heterogeneous fluid viscosity/density, significantly exacerbating the complexity of fluids flow. Meanwhile, the injected CO<sub>2</sub> in the formation becomes a supercritical state with high diffusivity and strong solubility, and causes oil expansion, density and viscosity reduction, interfacial tension reduction, wettability alteration and molecular diffusion, which effectively replaces adsorbed hydrocarbon components by competitive adsorption behaviors, and promotes oil flow. The challenges and outlook of molecular simulation research and upscaling applications are finally discussed. This review aims to provide a microscopic understanding of the distribution characteristics and flow behaviors of multiphase shale fluids in nanoconfined space for both unconventional oil and gas researchers and industry professionals.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104884"},"PeriodicalIF":10.8,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142076251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}