Earth-Science Reviews最新文献

{"title":"How many oceans closed during the Brasiliano Cycle in northeastern Brazil? Implications for the amalgamation of western Gondwana","authors":"Sérgio P. Neves","doi":"10.1016/j.earscirev.2024.104909","DOIUrl":"10.1016/j.earscirev.2024.104909","url":null,"abstract":"<div><p>In a pre-Mesozoic drift reconstitution, the Borborema Province in northeastern Brazil connects with the Central African Fold belt to the East and with the Nigerian and Tuareg shields to the North. Therefore, the Borborema Province is an important component to consider in the context of the amalgamation of western Gondwana. The tectonic setting of the Borborema Province has been debated, with some workers advocating for the accretion of allochthonous terranes and others arguing for the decratonization of a large continental landmass followed by the re-accretion of the fragments, either involving or not involving formation of large oceanic domains between them. Resolving the tectonic setting of the Borborema Province has implications for correlations with other Brasiliano-Pan-African belts and supercontinent reconstructions. This paper discusses proposed evidence for oceanic subduction, arc magmatism, and oceanic basin closure based on a comprehensive literature review. This information is integrated with data from the African counterparts of the Borborema Province to provide a geodynamic model for the Neoproterozoic evolution of this portion of western Gondwana. The main evidence for subduction is provided by ultra-high-pressure rocks and c. 660–640 Ma-old intermediate metaigneous rocks with relatively young (1.4–1.0 Ga) whole-rock Sm<img>Nd and zircon Hf model ages in the northwestern part of the Borborema Province. However, a key aspect of the Brasiliano Orogeny in most of the Borborema Province is its synchronous nature. Deposition of predominantly siliciclastic sediments throughout the province ended slightly before or partly coeval with c. 640–610 Ma tectonothermal activity and early orogenic magmatism. Plutons and batholiths emplaced during this age interval comprise predominantly alkali-calcic monzogranites and syenogranites with a large contribution of Paleoproterozoic sources. Together with the absence of juvenile oceanic crust remnants and calc-alkaline metavolcanic rocks, it is thus concluded that (i) widespread crustal extension was almost immediately followed by contractional deformation and regional metamorphism, and (ii) crustal reworking was the dominant process, with limited formation and consumption of oceanic lithosphere. A similar conclusion applies to the Nigerian Shield and the central and southern parts of the Central African Fold Belt. In contrast, large volumes of juvenile crust are found in the Tuareg Shield and in the northern part of the Central African Fold Belt. The model envisions that no large oceanic domain separated the São Francisco/Congo Craton from the Amazonian/West Africa Craton in the middle Neoproterozoic, which were part of the Atlantica paleocontinent since c. 2.0 Ga. Extensional conditions in the Borborema Province and its African counterparts are attributed to far-field stresses transmitted to the interior of Atlantica by an outwardly, N-dipping subduction system. The onset of the contractional ","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104909"},"PeriodicalIF":10.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142096106","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":"Evidence of a large igneous province at ca. 347–330 Ma along the northern Gondwana margin linked to the assembly of Pangea: Insights from U–Pb zircon geochronology and geochemistry of the South-Western Branch of the Variscan Belt (Morocco)","authors":"Oussama Moutbir , El Mostafa Aarab , Nasrrddine Youbi , Abdelhak Ait Lahna , Colombo Celso Gaeta Tassinari , João Mata , Ross N. Mitchell , Andreas Gärtner , Alvar Soesoo , Mohamed Khalil Bensalah , Abderrahmane Soulaimani , Moulay Ahmed Boumehdi , Ulf Linnemann","doi":"10.1016/j.earscirev.2024.104905","DOIUrl":"10.1016/j.earscirev.2024.104905","url":null,"abstract":"<div><p>The migration and composition of magmatism over time can provide important insights into the tectonic evolution of an orogen like the Variscan Belt. To identify Large Igneous Provinces (LIPs), key criteria include large magmatic volume, intraplate-origin volcanic geochemistry, and significant plumbing systems. Based on such criteria, we present evidence of ca. 347–330 Ma LIP “fragments” in the South-Western Branch of the Variscan Belt (Morocco), exemplified by the Variscan Central Jebilet Massif. The interpretations are based on four new zircon U–Pb ages obtained by sensitive high-resolution ion microprobe (SHRIMP), a geochemical database of Carboniferous mafic sills, dykes, and gabbroic intrusions together, with subordinate layered ultramafic intrusions, silicic intrusive and volcanic rocks of Central Jebilet Massif, combined with previously published and unpublished data including Sr–Nd isotope analyses. Geochemistry data indicate that the early Carboniferous magmatism of the Jebilet Massif is plume-related. Furthermore, primary magmas of the mafic rocks were generated in an intraplate setting and derived by partial melting of complex sources involving asthenosphere, lithospheric mantle, and subducting slab components (dead subduction slabs), and were modified by crustal contamination during ascent. Magmatic rocks in the same stratigraphic position also occur in other Carboniferous basins including Western Meseta (Rehamna and Moroccan Central Massif). The newly obtained and compiled zircon U–Pb ages from Western Meseta rocks, encompassing an area of ∼400,000 km<sup>2</sup>, indicate that magmatism occurred between ca. 347–330 Ma, coeval with volcanic activity in the Eastern Meseta in northeastern Morocco. The similar emplacement ages, in combination with the tectonic reconstruction of northwestern Gondwana at ca. 330 Ma, suggest that the igneous subprovinces of the Jebilet, Rehamna, and Moroccan Central Massif in Western Meseta, along with Tazekka, Debdou, and Mekkam in Eastern Meseta, the igneous rocks of the Maritimes (Magdalen) Basin, the St. Jean du Doigt bimodal layered intrusion (Brittany, France), and other equivalents such as the Iberian Pyrite Belt and the Southern Vosges magmatism, may represent the eroded and/or deformed remnants of a Large Igneous Province (LIP), which we name here the North Gondwana–Avalonia (NGA) LIP. We argue that this newly identified LIP was formed by a mantle plume that may have played a role in the breakup along the northwestern margin of the precursor megacontinent Gondwana and the assembly of Pangea. The plume was likely centered under the thick lithosphere of Avalonia. The large-scale sublithospheric plume-flow channeling from the plume head led to the development of widespread tholeiitic/alkaline magmatism in the thinned lithosphere of Western Meseta, interpreted here as a large thin-spot domain, and calc-alkaline/alkaline magmatism in the thickened lithosphere of the Eastern Meseta. The mantle pl","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"258 ","pages":"Article 104905"},"PeriodicalIF":10.8,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238573","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":"Mechanics of methane bubbles in consolidated aquatic muds","authors":"Regina Katsman","doi":"10.1016/j.earscirev.2024.104908","DOIUrl":"10.1016/j.earscirev.2024.104908","url":null,"abstract":"<div><p>Methane (CH₄) is a potent greenhouse gas that has a major impact on Earth's climate. CH₄ is accommodated in discrete bubbles in aquatic muds, whose sizes greatly exceed the pore size of the hosting sediment. This critical review examines the mechanics of CH₄ gas in consolidated aquatic muds at the scale of a single bubble and at a macroscale of gassy sediments, obtained from lab experiments, field observations, and numerical and analytical modeling. Linear elastic fracture mechanics (LEFM) theory is shown to control the single bubble shape, size, morphology, and inner pressure evolution over its entire life cycle. Reviewed implications focus on the effects of the inner bubble pressure on its solute exchange with ambient pore waters; on the dynamic water load effect (e.g., waves, tides) on the bubble growth rate and its release from sediment into the water column; and on competitive bubble pair growth in the aquatic muds, the process that presumably shapes the bubble size distribution pattern in muds. Alternatively, gassy sediment effective mechanical and physical characteristics and effective gassy media theories are examined at the macroscale, which makes them suitable for remote sensing acoustic applications. This review indicates, however, that most of the developed macroscale effective medium theories rely on the cumulative sediment gas content. Moreover, no theory for proper upscaling of the entire set of the microscale single bubble descriptors addressed in this review – bubble size distribution, their orientations and spatial locations, and inner bubble pressures – to the effective medium mechanical properties of gassy muds, exists. This review will serve, therefore, as a basis for the improved upscaling, while preserving the basic microscale bubble descriptors, their growth physics, and controls. Laying this foundation will enhance the accuracy of the acoustic applications. Improved assessment of sediment gas retention based on this upscaling will contribute to geohazard prediction and should reduce a long-persisting uncertainty related to CH₄ fluxes from the aquatic sediments.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104908"},"PeriodicalIF":10.8,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149431","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":"Reply to Discussion: “Haiyang Zhang and Muhammad Arif. Residual trapping capacity of subsurface systems for geological storage of CO2: Measurement techniques, meta-analysis of influencing factors, and future outlook. Earth-Science Reviews (2024): 104764.”","authors":"Haiyang Zhang,&nbsp;Muhammad Arif","doi":"10.1016/j.earscirev.2024.104907","DOIUrl":"10.1016/j.earscirev.2024.104907","url":null,"abstract":"<div><p>Geological storage of CO₂ is a promising technique to mitigate anthropogenic CO₂ emissions. The effectiveness of CO₂ storage in the subsurface formations relies on various trapping mechanisms that immobilize the injected CO₂. Among these mechanisms, residual trapping has been identified as a critical factor, closely associated with residual CO₂ saturation. The extent of residual CO₂ saturation is strongly influenced by the petrophysical physicochemical and hydrodynamic properties of CO₂/fluid/rock systems and operational conditions, thereby governing the overall residual trapping efficiency.</p><p>This article reviews the published experimental datasets on the initial and residual CO₂ saturation and analyzes the corresponding trapping efficiency for a range of in-situ CO₂/fluid/rock systems. We explore the factors that influence trapping efficiency, including wettability, rock type, rock properties, and flow rate. The gas saturations and trapping efficiencies of different gas types (i.e., CO₂, N₂, and H₂) are also discussed. Finally, we present the knowledge gaps and outline prospects for future research. This review establishes a state-of-art data repository of gas saturations in different conditions, enhancing our understanding of residual trapping in subsurface gas storage.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104907"},"PeriodicalIF":10.8,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142049758","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":"Quantifying the pattern of organic carbon burial through Cretaceous Oceanic Anoxic Event 2","authors":"Huifang Guo ,&nbsp;Xi Chen ,&nbsp;Hanwei Yao ,&nbsp;Yinggang Zhang ,&nbsp;Benjamin J.W. Mills ,&nbsp;Kaibo Han ,&nbsp;Shujuan Wu ,&nbsp;Yida Yang ,&nbsp;Zihao Wang ,&nbsp;David B. Kemp","doi":"10.1016/j.earscirev.2024.104903","DOIUrl":"10.1016/j.earscirev.2024.104903","url":null,"abstract":"<div><p>The Cenomanian-Turonian Oceanic Anoxic Event 2 (OAE 2, ca. 94 Ma) is characterized by a marked positive carbon isotope excursion (CIE) recorded in global marine basins. This CIE results from a global-scale increase in organic matter burial, facilitated by high productivity and seawater deoxygenation. To date, however, the precise pattern of changes in the burial rate of organic matter through the event has not been well constrained. In this work, we present a compilation of data from 42 globally distributed OAE 2 sites, as well as organic carbon isotope (<span><math><mi>δ</mi></math></span>¹³C_org), total organic carbon (TOC), and trace element concentration data from a new OAE 2 interval in southern Tibet, China. In southern Tibet, the absence of redox-sensitive trace element enrichment through OAE 2 indicates prevailing oxic conditions. Organic carbon (OC) mass accumulation rate (MAR) at this site decreased from the lower part of the CIE to the upper part, in contrast to an approximate doubling of organic carbon MAR in the upper part observed globally. This result, coupled with detailed analysis of the compilation, shows that redox was a key factor controlling organic burial rates during OAE 2, with OC MAR scaling positively with increasing deoxygenation. Leveraging a biogeochemical model to simulate these data suggets that 5–20% of the seafloor became anoxic during OAE 2, and that this deoxygenation was accompanied by 100% to 200% increase in global seawater P concentration. Our findings indicate that during OAE 2, elevated nutrient levels may have resulted from enhanced recycling from sediments under reducing conditions, sustaining intensified primary production and subsequent organic carbon export and burial.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104903"},"PeriodicalIF":10.8,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149522","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 uplift of the East Africa - Arabia swell","authors":"Andrea Sembroni ,&nbsp;Claudio Faccenna ,&nbsp;Thorsten W. Becker ,&nbsp;Paola Molin","doi":"10.1016/j.earscirev.2024.104901","DOIUrl":"10.1016/j.earscirev.2024.104901","url":null,"abstract":"<div><p>The East Africa - Arabia topographic swell is an anomalously high-elevation region of ∼4000 km long (from southern Ethiopia to Jordan) and ∼ 1500 km wide (from Egypt to Saudi Arabia) extent. The swell is dissected by the Main Ethiopian, Red Sea, and Gulf of Aden rifts, and characterized by widespread basaltic volcanic deposits emplaced from the Eocene to the present. Geochemical and geophysical data confirm the involvement of mantle processes in swell formation; however, they have not been able to fully resolve some issues, e.g., regarding the number and location of plumes and uplift patterns. This study addresses these questions and provides a general evolutionary model of the region by focusing on the present topographic configuration through a quantitative analysis and correlating long and intermediate wavelength features with mantle and rifting processes. Moreover, the isostatic and dynamic components of topography have been evaluated considering a range of seismic tomographic models for the latter. When interpreted jointly with geological data including volcanic deposits, the constraints do imply causation by a single process which shaped the past and present topography of the study area: the upwelling of the Afar superplume. Once hot mantle material reached the base of the lithosphere below the Horn of Africa during the Late Eocene, the plume flowed laterally toward the Levant area guided by pre-existing discontinuities in the Early Miocene. Plume material reached the Anatolian Plateau in the Late Miocene after slab break-off and the consequent formation of a slab window. During plume material advance, buoyancy forces led to the formation of the topographic swell and tilting of the Arabia Peninsula. The persistence of mantle support beneath the study area for tens of million years also affected the formation and evolution of the Nile and Euphrates-Tigris fluvial networks. Subsequently, surface processes, tectonics, and volcanism partly modified the initial topography and shaped the present-day landscape.</p></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"257 ","pages":"Article 104901"},"PeriodicalIF":10.8,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0012825224002289/pdfft?md5=c84fbe63fb920ffba7310b61e0499016&pid=1-s2.0-S0012825224002289-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142043746","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 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 ,&nbsp;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,&nbsp;Vikas Adlakha","doi":"10.1016/j.earscirev.2024.104890","DOIUrl":"10.1016/j.earscirev.2024.104890","url":null,"abstract":"&lt;div&gt;&lt;p&gt;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}

{"title":"Fracture sets and sequencing","authors":"David J. Sanderson ,&nbsp;David C.P. Peacock ,&nbsp;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}

{"title":"Desertification baseline: A bottleneck for addressing desertification","authors":"Dongwei Gui ,&nbsp;Qi Liu ,&nbsp;Jaime Martínez-Valderrama ,&nbsp;Sameh Kotb Abd-Elmabod ,&nbsp;Zeeshan Ahmed ,&nbsp;Zhiwei Xu ,&nbsp;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}