Earth-Science Reviews最新文献

{"title":"Fringed Patagonian tableland: One of Earth's largest and oldest landslide terrains","authors":"Jakub Kilnar ,&nbsp;Tomáš Pánek ,&nbsp;Michal Břežný ,&nbsp;Diego Winocur ,&nbsp;Karel Šilhán ,&nbsp;Veronika Kapustová","doi":"10.1016/j.earscirev.2024.104926","DOIUrl":"10.1016/j.earscirev.2024.104926","url":null,"abstract":"<div><p>Sedimentary and volcanic tablelands host the world's largest landslide areas, sometimes spanning hundreds of kilometers along escarpments. This study, employing new remote sensing-based mapping and drawing on an expanding body of literature on paleogeographic evolution, revises the extent, controls, and chronology of some of Earth's largest coalescent landslides in the volcanic tableland of extra-Andean Patagonia. Mostly ancient rotational slides and rock spreads, accompanied by earthflows and occasional rock avalanches, cover approximately 30,000 km², roughly a fifth of the Patagonian escarpments, with the largest landslide areas exceeding 1000 km². The immense size of the failed tableland in Patagonia is inherited from stratigraphy and geological history: weak marine and continental Cretaceous-Miocene sedimentary and volcaniclastic rocks, capped by plateau basalts, create a highly unstable environment, outcropping along thousands of kilometers of escarpments. Most landslide areas occupy the steepest, most dissected parts of Patagonian tableland, occurring independently of recent climatic conditions. Some of the largest complexes are found in both the most humid and arid regions. Cross-cutting relationships between landslides and dated glacial, lacustrine, marine deposits, and lava flows reveal that some landslides have persisted for several million years, marking them as some of Earth's oldest landslide terrains with distinctive geomorphological footprints. Future research on failed Patagonian tableland should include direct radiometric dating, InSAR technology monitoring, and numerical stability modeling of landslides. This comprehensive approach will deepen our understanding of their origins and determine whether these giant landslide fringes predominantly represent fossil features or could be reactivated under contemporary environmental conditions.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104926"},"PeriodicalIF":10.8,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142172337","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":"A benchmark dataset and workflow for landslide susceptibility zonation","authors":"Massimiliano Alvioli ,&nbsp;Marco Loche ,&nbsp;Liesbet Jacobs ,&nbsp;Carlos H. Grohmann ,&nbsp;Minu Treesa Abraham ,&nbsp;Kunal Gupta ,&nbsp;Neelima Satyam ,&nbsp;Gianvito Scaringi ,&nbsp;Txomin Bornaetxea ,&nbsp;Mauro Rossi ,&nbsp;Ivan Marchesini ,&nbsp;Luigi Lombardo ,&nbsp;Mateo Moreno ,&nbsp;Stefan Steger ,&nbsp;Corrado A.S. Camera ,&nbsp;Greta Bajni ,&nbsp;Guruh Samodra ,&nbsp;Erwin Eko Wahyudi ,&nbsp;Nanang Susyanto ,&nbsp;Marko Sinčić ,&nbsp;Jhonatan Rivera-Rivera","doi":"10.1016/j.earscirev.2024.104927","DOIUrl":"10.1016/j.earscirev.2024.104927","url":null,"abstract":"&lt;div&gt;&lt;p&gt;Landslide susceptibility shows the spatial likelihood of landslide occurrence in a specific geographical area and is a relevant tool for mitigating the impact of landslides worldwide. As such, it is the subject of countless scientific studies. Many methods exist for generating a susceptibility map, mostly falling under the definition of statistical or machine learning. These models try to solve a classification problem: given a collection of spatial variables, and their combination associated with landslide presence or absence, a model should be trained, tested to reproduce the target outcome, and eventually applied to unseen data.&lt;/p&gt;&lt;p&gt;Contrary to many fields of science that use machine learning for specific tasks, no reference data exist to assess the performance of a given method for landslide susceptibility. Here, we propose a benchmark dataset consisting of 7360 slope units encompassing an area of about &lt;span&gt;&lt;math&gt;&lt;mn&gt;4,100&lt;/mn&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;km&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; in Central Italy. Using the dataset, we tried to answer two open questions in landslide research: (1) what effect does the human variability have in creating susceptibility models; (2) how can we develop a reproducible workflow for allowing meaningful model comparisons within the landslide susceptibility research community.&lt;/p&gt;&lt;p&gt;With these questions in mind, we released a preliminary version of the dataset, along with a “call for collaboration,” aimed at collecting different calculations using the proposed data, and leaving the freedom of implementation to the respondents. Contributions were different in many respects, including classification methods, use of predictors, implementation of training/validation, and performance assessment. That feedback suggested refining the initial dataset, and constraining the implementation workflow. This resulted in a final benchmark dataset and landslide susceptibility maps obtained with many classification methods.&lt;/p&gt;&lt;p&gt;Values of area under the receiver operating characteristic curve obtained with the final benchmark dataset were rather similar, as an effect of constraints on training, cross–validation, and use of data. Brier score results show larger variability, instead, ascribed to different model predictive abilities. Correlation plots show similarities between results of different methods applied by the same group, ascribed to a residual implementation dependence.&lt;/p&gt;&lt;p&gt;We stress that the experiment did not intend to select the “best” method but only to establish a first benchmark dataset and workflow, that may be useful as a standard reference for calculations by other scholars. The experiment, to our knowledge, is the first of its kind for landslide susceptibility modeling. The data and workflow presented here comparatively assess the performance of independent methods for landslide susceptibility and we suggest the benchmark approach as a best practice for quantitative research in geosciences.&lt;/p","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104927"},"PeriodicalIF":10.8,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0012825224002551/pdfft?md5=ec4ffeb5b8f126bf82473e863d41ca1f&pid=1-s2.0-S0012825224002551-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238447","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":"Insights into the assessment and interpretation of earthquake-induced liquefaction in sands under different degrees of saturation","authors":"Fausto Molina-Gómez ,&nbsp;António Viana da Fonseca ,&nbsp;Cristiana Ferreira ,&nbsp;Bernardo Caicedo","doi":"10.1016/j.earscirev.2024.104925","DOIUrl":"10.1016/j.earscirev.2024.104925","url":null,"abstract":"<div><p>Earthquake-induced liquefaction is a prominent and impactful natural hazard responsible for substantial economic losses worldwide. Hence, engineers and researchers are currently interested in developing methods and techniques to mitigate this destructive phenomenon. Reducing the degree of saturation is a reliable method to improve the liquefaction resistance of sandy soils since it directly influences the pore pressure build-up during seismic action. This paper reviews the mechanisms and assessment of earthquake-induced liquefaction in sandy soils with various degrees of saturation, a crucial parameter for reducing the phenomenon triggering. In addition, it presents novel approaches that delve into interpreting cyclic behaviour with diverse degrees of saturation using stress-based and energy-based approaches. The experimental results compiled and discussed show that, effectively, reducing the degree of saturation holds promise as a viable strategy for enhancing soil liquefaction resistance and mitigating associated risks. Moreover, the interpretation of cyclic behaviour addressed in this paper offers valuable insights into the reliability of interpreting methods to quantify the liquefaction resistance under several degrees of saturation (that may be achieved by desaturation or induced partial saturation techniques), contributing to strategies for resilience against earthquake-induced damages.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104925"},"PeriodicalIF":10.8,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229441","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":"Formation mechanism and geophysical properties of fracture-filling gas hydrate in the host sediments: A comprehensive review","authors":"Gaowei Hu ,&nbsp;Zhun Zhang ,&nbsp;Yapeng Zhao ,&nbsp;Qingtao Bu ,&nbsp;Ang Li ,&nbsp;Wengao Zhao ,&nbsp;Zihao Wang ,&nbsp;Xiaoqian Qiu ,&nbsp;Tong Liu ,&nbsp;Shengbiao Liu ,&nbsp;Wanjun Lu ,&nbsp;Nengyou Wu","doi":"10.1016/j.earscirev.2024.104917","DOIUrl":"10.1016/j.earscirev.2024.104917","url":null,"abstract":"<div><p>Fracture-filling hydrate constitutes a pivotal component within the global hydrate reserves and serve as a significant focal point for hydrate exploration and development. However, the understanding of the formation mechanisms and geophysical properties of fracture-filling hydrate in sediments remains unclear. This review seeks to bridge this knowledge gap by comprehensively examining the formation mechanisms of fracture-filling hydrate from both micro-sedimentary and geological reservoir perspectives. It delves into various aspects of field tests, including seismic and logging, as well as laboratory tests covering acoustic properties, permeability, thermal properties, electrical resistivity, and mechanical properties. It aims to shed light on the challenges associated with the characteristics of fracture-filling hydrate reservoirs and their geophysical properties while proposing potential solutions, and emphasizes the urgency of identifying the formation patterns of fracture-filling hydrate and estimating resource volumes. Furthermore, the review emphasizes the importance of collaborative geophysical characterization testing for fracture-filling hydrate as a crucial step in addressing this challenge. It advocates for fostering international cooperation for global data integration and sharing as a viable solution to advance our understanding and management of these valuable resources.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104917"},"PeriodicalIF":10.8,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233876","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":"Dynamics of nutrient cycles in the Permian–Triassic oceans","authors":"Yadong Sun","doi":"10.1016/j.earscirev.2024.104914","DOIUrl":"10.1016/j.earscirev.2024.104914","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Marine biochemical cycles underwent profound changes across the Permian–Triassic (P–T) transition, coinciding with Phanerozoic’s most devastating mass extinction. This review endeavours to untangle the complexity of marine biochemical cycles at this time, focusing on key components of the oceanic nutrient cycles, namely the nitrogen, phosphorus, iron, and molybdenum cycles.&lt;/div&gt;&lt;div&gt;The oceanic nitrogenous nutrient structure saw the shift from nitrate to ammonium dominance in warm and anoxic P–T waters. Nitrogen isotope evidence suggests enhanced denitrification began in the latest Permian, followed by augmented N&lt;sub&gt;2&lt;/sub&gt; fixation in the Early Triassic. As nitrification was inhibited by prolonged and widespread anoxia while denitrification enhanced in the same conditions, nitrate was probably depleted while ammonium accumulated. Thus, the lost oceanic fixed-N should have been compensated by enhanced N&lt;sub&gt;2&lt;/sub&gt;-fixation if the oceanic nutrient-N inventory was in balance. Such changes altered microbial respiration efficiency, promoted algal blooms, and possibly caused ammonium toxication.&lt;/div&gt;&lt;div&gt;A phosphorus burial anomaly is registered in the P–T marine sediments, featuring reduced burial of biogenic apatite and organic phosphorus, a phosphorite gap in continental margins, and unusual diagenetic phosphate replacement in calcitic and aragonitic fossils. This suggests decreased reactive phosphorus availability in shallow waters, conflicting with the expected increase from riverine inputs. This discrepancy points to P sequestration in shelf seas and deep waters, resulting in reactive P deficiency in open surface water. The delivery of riverine nutrients to the open ocean was difficult because of the largely dry Pangaea interiors, enlarged coastal areas, and strong sediments trapping and nutrient uptakes by primary producers in epicontinental seas. This probably led to a general lack of detrital nutrients in Panthalassa.&lt;/div&gt;&lt;div&gt;Iron (Fe) dynamics were equally complex, primarily influenced by atmospheric deposition and oceanic redox conditions. Fe availability in the P–T oceans depended not only on Pangaea’s configuration but, more significantly, on the oceanic redox evolution. As anoxia mobilises sedimentary Fe and facilitates lateral Fe transportation, Fe limitation was more likely to occur in the Permian ocean than in the anoxic Early Triassic ocean. The development of the Lower Triassic ammonitico rosso facies in Neotethys also points to replete Fe supply to the open water.&lt;/div&gt;&lt;div&gt;Molybdenum (Mo) likely became a bio-limiting nutrient in the P–T oceans, due to strong Mo removal in anoxic environments. With a small input into a large sink, Mo scarcities could have been prominent in the open ocean. Even in epicontinental seas, Mo depletion is indicated by low nitrogen isotope values that are suggestive of an absence of Mo-Fe nitrogenase.&lt;/div&gt;&lt;div&gt;Changes in the nutrient cycle impacted the P–T marine productivity, which is f","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104914"},"PeriodicalIF":10.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326477","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":"Well log prediction of total organic carbon: A comprehensive review","authors":"Jin Lai ,&nbsp;Fei Zhao ,&nbsp;Zongli Xia ,&nbsp;Yang Su ,&nbsp;Chengcheng Zhang ,&nbsp;Yinhong Tian ,&nbsp;Guiwen Wang ,&nbsp;Ziqiang Qin","doi":"10.1016/j.earscirev.2024.104913","DOIUrl":"10.1016/j.earscirev.2024.104913","url":null,"abstract":"<div><div>Source rocks are fundamental elements for petroleum systems, and Total Organic Carbon (TOC) is one of the most important geochemical parameters in source rock property evaluation. The TOC determination methods using laboratory tests are expensive and limited, therefore prediction of TOC using geophysical well logs are vital for source rock characterization. Though there are various proposed TOC quantitation method, however, there still remains large uncertainty in delineation and quantitation of TOC using well log data due to the complex non-linear relationships between TOC and well log information, as well as the inherent limitations of various methods for TOC prediction. To fill the gaps between TOC and well logs, and eliminate uncertainties existing in empirical methods such as ΔlgR method, the geological, geophysical and geochemical data are integrated. History of source rock evaluation using well logs is reviewed, and sensitive well log parameters for source rocks are selected. The TOC content is correlated with well log series to unravel the well log responses of source rock intervals, and the organic matter rich intervals have high Uranium (U) concentrations and gamma ray (GR) readings, high sonic transit time (AC) and compensated neutron log (CNL), high resistivity, but low density readings. Then the various methods used for TOC quantitation are summarized in terms of their principles, interpretation process, and advantage and limitations. The Schmoker method is not applicable in shales, and borehole regularity will affect the linear regression relationship between TOC and bulk density. The Passey's ΔlgR method is widely used, however, the baseline selection will reduce the accuracy, and ΔlgR method is not applicable in highly mature or deep burial source rocks. The multiple regression analysis is hard to extend in other source rocks. The spectral GR method can hardly be used for lacustrine source rock analysis. The high acquisition costs of Nuclear Magnetic Resonance (NMR) and spectral mineral composition log (Schlumberger's Litho-Scanner logs) limit their extension in source rock evaluation. Artificial intelligence methods such as Back propagation (BP) neural network, Extreme Gradient Boosting (XGBOOST) can be used to predict TOC content via conventional logs, and the results are compared with the geochemical-measured TOC and ΔlgR method. The optimization of various methods for TOC prediction should fully consider their advantage and limitations. Additionally, comprehensive assessment of source rock should determine TOC, quality, and maturity of source rocks. This comprehensive review provides systematic and novel insights in applications of well logs in source rock evaluation, and has potential to fill gaps between geologists, geochemists and petrophysicists.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104913"},"PeriodicalIF":10.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319882","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":"The Ediacaran paleontological record in South America","authors":"Lucas V. Warren ,&nbsp;Bruno Becker-Kerber ,&nbsp;Lucas Inglez ,&nbsp;Filipe G. Varejão ,&nbsp;Luana P.C. Morais ,&nbsp;Marcello G. Simões ,&nbsp;Bernardo T. Freitas ,&nbsp;Julia M. Arrouy ,&nbsp;Lucía E. Gómez-Peral ,&nbsp;Daniel G. Poiré ,&nbsp;Juliana Okubo ,&nbsp;Fabrício Caxito ,&nbsp;Gabriel J. Uhlein ,&nbsp;Gabriel C. Antunes ,&nbsp;Ilana Lehn ,&nbsp;Guilherme R. Romero ,&nbsp;Thomas R. Fairchild","doi":"10.1016/j.earscirev.2024.104915","DOIUrl":"10.1016/j.earscirev.2024.104915","url":null,"abstract":"<div><p>South America figures as one of the most fruitful continents for paleontological research on the Ediacaran-Cambrian transition, with almost 100 years of studies on organisms preserved in carbonates and siliciclastic successions deposited during the birth of the Gondwana supercontinent. However, this scientific record is often scattered among local publications which is part of the reason for the unfamiliarity of geoscientists with the Ediacaran paleontology of this continent. To address this issue, this paper provides a comprehensive overview of Ediacaran paleontology in South America. It achieves this by conducting a thorough assessment of existing research alongside presenting ample new data concerning fossil discoveries. Following current efforts to add new pieces to the complex puzzle on metazoan evolution, this contribution resumes our understanding of the variety and diversity of Ediacaran assemblages in this part of the planet. Positioning South American successions in space and time and comparing them with occurrences worldwide helps us understand the different pulses of extinctions, and their forcings and consequences for life diversification during the Ediacaran. Lastly, by definitively adding the paleontological record of SW Gondwana to the global picture, we seek to contribute to current discussions on the subdivision of the Ediacaran, perhaps the most emblematic period in the geological record.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104915"},"PeriodicalIF":10.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142162901","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":"Impact catastrophism versus mass extinctions in retrospective, perspective and prospective: Toward a Phanerozoic impact event stratigraphy","authors":"Grzegorz Racki ,&nbsp;Christian Koeberl","doi":"10.1016/j.earscirev.2024.104904","DOIUrl":"10.1016/j.earscirev.2024.104904","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Despite several, sometimes prominent propagators, meteorite impact research had a long period of peripheral status until the 1980s. Since then, there has been an intense search for impact-extinction pairs, driven by the rapid acceptance of Alvarez's hypothesis of a catastrophic Chicxulub impact at the end of the Mesozoic era. However, substantial errors have occurred for incompletely identified and/or indirectly dated impact craters in the context of purportedly coeval mass extinctions. For example, supposed giant craters based only on geophysical studies, such as those alleged as evidence of impact-driven end-Permian and Late Ordovician extinctions, are not supported by any real impact evidence (e.g., catastrophic sedimentation) in adjacent areas.&lt;/div&gt;&lt;div&gt;The updated three-step methodology presents an accurate approach to cause-effect inference in impact catastrophism. It begins with (1) conclusive recognition of impact craters and ejecta, followed by (2) their precise radiometric or biostratigraphic dating, and concludes with (3) assessing the impact's “kill” potential. The impact contribution to widely defined mass extinctions has been falsified based on the latest crater information from the global database and the updated ages of stratigraphic boundaries. In the Phanerozoic, two contrasting collision phenomena occurred: the Chicxulub asteroid mega-impact and a prolonged asteroid shower from a shattered chondritic body in the Middle to Late Ordovician. Accordingly, a distinction has been proposed between steady background conditions (impacts occurring singly and rarely in clusters) and perturbation (bombardment) intervals. Current evidence for an impact trigger has been reviewed in detail for the other four Big Five mass extinctions, but no confirmation has been found. The probability of a prolonged impact-enhanced Late Eocene to Early Oligocene crisis, caused by an asteroid shower, is considered, as well as biotic changes accompanying other major cratering events: the mid-Norian Manicouagan and the end-Jurassic Morokweng structures. In particular, for the Popigai asteroid swarm, implied from paired 100-km-sized craters, and the possible Morokweng-Mjølnir coincidence, the relationships between impact signatures and likely stepwise biotic events are far from conclusive. Even if medium-sized bolide impacts, recorded in ∼40-km-diameter craters, may have initiated near-global climatic hazards, the killing effect is unpredictable due to the diversity of cataclysm severity controls. Also the Ordovician cosmic bombardment did not have any negative influence on the great biodiversification. However, the asteroid swarms may have (by unusual dustiness of the inner Solar System) ultimately triggered or accelerated ice ages in the Late Ordovician and Oligocene, respectively. Overall, this implies a continuum in the biosphere's response to extraterrestrial stimuli.&lt;/div&gt;&lt;div&gt;Furthermore, a first attempt was made to explain the hidden record of","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"259 ","pages":"Article 104904"},"PeriodicalIF":10.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655603","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":"Review of the missing link between field and modeled submarine debris flows: Scale effects of physical modeling","authors":"Clarence Edward Choi,&nbsp;Jiantao Yu,&nbsp;Jiaqi Zhang","doi":"10.1016/j.earscirev.2024.104911","DOIUrl":"10.1016/j.earscirev.2024.104911","url":null,"abstract":"<div><p>Submarine debris flows occur under the cloak of the sea and are giants among other types of landslides on planet Earth. They pose a significant threat to sustainable offshore development and marine ecosystems. Existing research on these flows mainly rely on back-analyzing field events and conducting miniaturized experiments. However, it is unclear whether the dynamics of miniaturized flows are similar to field ones. In this review, dimensional analysis is used to evaluate laboratory and field data collated from the literature to compare the dynamics of submarine debris flows at different scales. Miniaturized flows are demonstrated to have disproportionately low yield stress and viscosity compared to field flows. The low yield stress is caused by the need to reduce the clay content of a model debris mixture so that it can flow under substantially reduced gravitational driving stresses in laboratory conditions. Consequently, some proposed scaling relationships in the literature derived from laboratory experiments need to be used with caution. Specifically, both the Reynolds and Bingham numbers cannot independently provide a scale-invariant criterion for distinguishing between laminar and turbulent flows. Instead, the Hampton number, with a threshold &gt;0.001, is proposed for the design of the yield stress and clay contents of laboratory flows. Moreover, reduced model viscous stress drastically reduces erosion potential, which limits the existing understanding of the excess fluid pressures generated at the flow-bed interface, and thus flow mobility. The mobility of field flows is generally attributed to hydroplaning. However, this conjecture mainly stems from experiments with impervious boundaries. Such an idealization exaggerates the effects of excess fluid pressures that develop during hydroplaning. An enhanced understanding of the differences in dynamics between field and modeled flows can improve the design of future experiments to model submarine debris flows.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104911"},"PeriodicalIF":10.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142162900","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":"A review of abyssal serpentinite geochemistry and geodynamics","authors":"Baptiste Debret ,&nbsp;Muriel Andreani ,&nbsp;Marguerite Godard","doi":"10.1016/j.earscirev.2024.104910","DOIUrl":"10.1016/j.earscirev.2024.104910","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The formation of abyssal serpentinites leads to deep changes of the oceanic lithosphere rheology and geochemistry, hence playing a key role on geodynamic and geochemical cycles. Here we review and discuss the geochemical diversity of serpentinites collected on abyssal floors (i.e., abyssal serpentinites) from different geodynamical settings, namely passive margin, forearc and oceanic spreading ridges. We further divided abyssal serpentinites from spreading ridges according to the tectonic contexts in which they were exhumed, differentiating slow-spreading centres (exhumed within the axial valleys and at oceanic detachments), ultra-slow spreading centres (from amagmatic axial valleys and smooth seafloor), fast spreading axis (mostly from deeps) and large transform faults (all spreading rates).&lt;/p&gt;&lt;p&gt;The major and trace element composition of abyssal serpentinites is first controlled by melt extraction and melt/rock interaction processes occurring prior to serpentinization. Slow-, fast- spreading ridges and forearc serpentinites are distinguished by low Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;/SiO&lt;sub&gt;2&lt;/sub&gt; ratios and depleted REE signatures when compared to abyssal serpentinites recovered from ultra-slow spreading ridges, transform faults and passive margins, where magmatic extraction is likely more limited or/and melt/rock reaction prominent. Ultra-slow spreading ridge serpentinites have high Fe&lt;sup&gt;3+&lt;/sup&gt;/∑Fe when compared to passive margin and forearc serpentinites, while slow spreading ridge and transform fault serpentinites have intermediate Fe&lt;sup&gt;3+&lt;/sup&gt;/∑Fe, close to that of magnetite. This distribution is correlated with MgO/SiO&lt;sub&gt;2&lt;/sub&gt; ratios, suggesting that high MgO contents could thwart Fe oxidation, and thus H&lt;sub&gt;2&lt;/sub&gt; production, in abyssal environments.&lt;/p&gt;&lt;p&gt;The presence of mafic units at depth affects the chemical properties (e.g., sulfur activity [&lt;em&gt;a&lt;/em&gt;H&lt;sub&gt;2&lt;/sub&gt;S], oxygen fugacity (&lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt;)) of the serpentinizing fluids leading to contrasting enrichments of redox sensitive elements (S, U, Eu, Ce, As, Sb) and metals (Zn, Cu) in abyssal serpentinites. At slow-spreading ridges, the circulation of high &lt;em&gt;a&lt;/em&gt;H&lt;sub&gt;2&lt;/sub&gt;S and low &lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt; fluids, equilibrated with gabbroic rocks, leads to the formation of serpentinites with pronounced Eu anomalies, enrichments of LREE over M-HREE and of As over Sb, and to the storage of metal (Zn, Cu) and sulfide in serpentinites. In contrast, at ultra-slow spreading ridges and at transform faults, the absence of an active magmatic system limits changes in seawater composition prior to serpentinization. The oxidizing conditions favours Ce(IV) (Ce anomalies on REE patterns), and the preferential mobility of Sb(V) over Sb(III) (coupled behaviour between Sb and As), as well as the storage of sulfate over sulfides in rocks. Fast spreading ridge serpentinites present both features with samples having negative Ce anomaly (Ce (IV)) and others with positiv","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104910"},"PeriodicalIF":10.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S001282522400237X/pdfft?md5=2510cc0120060dbc7fb50ca53ba321ae&pid=1-s2.0-S001282522400237X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229442","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}