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Effective selection of climate predictors is a fundamental aspect of climate modeling research. Predictor Screening (PS) plays a crucial role in identifying regional climate drivers, reducing noise, expediting convergence, and minimizing time consumption, ultimately leading to the development of robust models. This review delves into the complex landscape of PS techniques within the context of Numerical Climate Modeling (NCM), with a specific focus on their applicability across various Köppen climate classifications and PS model structures. The analysis revealed substantial variations in the performance of PS methods, shedding light on their ability to capture –and prioritize predictors related to precipitation and temperature within distinct climate contexts. Furthermore, the provided methods have been categorized into two subsections: Feature Selection (FS) and Feature Extraction (FE), with FS encompassing filter, wrapper, embedded, and ensemble/hybrid techniques, and FE covering Linear Feature Extraction (LFE), Time-Domain Analysis (TDA), deep learning, and clustering methods. The initial compilation of papers, acquired through a keyword search on Scopus, consisted of 3650 documents. Following a meticulous evaluation process, 206 papers were identified as fitting for inclusion in the literature review, covering the time frame from 1974 to November 3, 2023. In conclusion, the results provide a detailed understanding of the strengths and limitations of each approach, establishing a hierarchy of effectiveness contingent upon the specific climate context. Additionally, insights into promising avenues for future research in this field are offered. This review follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standard as its foundation. [ABSTRACT FROM AUTHOR]

As a vital freshwater resource for one-sixth of the world's population, snowmelt provides great convenience for residents in terms of livelihood and production, agricultural irrigation, and hydroelectric power generation. However, snowmelt can also have an important impact on the formation of surface runoff and the process of soil erosion. In contrast to glacier melt, snowmelt erosion has received relatively little attention in the past. This paper reviewed the generation of snowmelt runoff, the characteristics of erosion and sediment yield during snowmelt, the snowmelt erosion mechanism, and the applications of snowmelt modeling. The published results of sediment yield driven from snowmelt runoff ranged from 1 to 300 t km−2 a−1, with the largest value of 1114 t km−2 a−1. Snowmelt erosion is extremely sensitive to warming climate. With global warming, there is a trend towards earlier snowmelt periods and a significant increase in runoff volume, as well as a significant increase in sediment yield from snowmelt in most of the study cases. Moreover, snowmelt erosion compared to rainfall erosion has more complex mechanistic processes which can be influenced by various factors such as snowfall, freeze-thaw, topography, etc. In particular, the occurrence of rain-on-snow events will lead to more severe soil erosion. In addition, current studies of sediment yield from snowmelt erosion account for a small percentage of snowmelt, and snowmelt erosion modeling is rarely applied in practical studies. In future research, the field monitoring of snowmelt erosion in the context of climate change needs to be further strengthened and the effects of multiple factors on snowmelt erosion need to be investigated. The inclusion of rain-on-snow and specific erosion types in the model will improve the applicability of models under climate change scenarios and in multi-scale environments. This paper is intended to show the achievements as well as the limitations of snowmelt erosion research, while suggesting future research directions that need to be further explored and developed for better understanding and forecasting of snowmelt erosion. [ABSTRACT FROM AUTHOR]

Groundwater plays an essential role in Africa and corresponding research is vital to resource management and long-term planning. However, the level of research output and the mode of international research collaboration on the continent have been questioned. In particular, cases of "helicopter research" have been reported. The term implies that scientists from wealthy nations do research in lower-income countries without involving local collaborators. To investigate the phenomenon in a groundwater context, we performed a bibliometric study by extracting and analyzing (meta)data from Clarivate's Web of Science database for the time period 1991–2020. Here, we particularly focused on authors and their affiliations. The analysis showed that there is a pronounced intra-continental imbalance and that much of the groundwater research output in Africa is produced by Egypt, Nigeria, South Africa, Tunisia, and Morocco – larger countries with a relatively high Gross Domestic Product. These nations apparently "own" their research, i.e., papers about groundwater in these countries include local (co-)authors (affiliation in the concerned country), or at least authors with an African affiliation. However, this does not apply to a number of other African countries, implying that local scientists do not spearhead corresponding studies which points towards helicopter research. To foster effective groundwater research and counteract the above-mentioned development, various players have to contribute, including local governments, funding organizations, individual researchers, but also journals. [ABSTRACT FROM AUTHOR]

Chile is the world's leading producer of many terrestrial mineral resources; however, the potential of the country's marine mineral resources has been largely overlooked. Within its continental shelf (up to 200 nautical miles from the baselines from which the breadth of the territorial sea is measured), Chile has favorable geological characteristics for hosting and forming marine minerals and energy resources. During the last decades, several novel studies have demonstrated the potential of gas hydrate reservoirs in Chile (between 33° and 56°S) as an energy resource and source of greenhouse gases, which has attracted the attention of the Chilean scientific community. In addition, some studies have highlighted the potential value of marine minerals in the Chilean continental shelf, mainly due to the increasing demand for minerals for low-carbon energy production, such as cobalt-rich ferromanganese crusts, polymetallic nodules, and massive sulfides on the seafloor. The goal of this study is to review all information on the non-conventional energy and mineral resources of the Chilean continental shelf. Furthermore, we provide data (e.g., core samples, seismic profiles, or research from related papers) on marine deposits in the Chilean seabed. Here, we show unpublished seismic images of a previously unidentified massive hydrate deposit in the southernmost part of the 1960 Valdivia earthquake rupture zone, which was the largest earthquake recorded in history. We also present geological data that suggests the presence of nodules, sulfides, and crusts on the Chilean continental shelf. Collectively, these findings represent the most important but least explored resources for critical elements and base metals in the country. This study provides a primer for policymakers to apprise them of future research needed to develop potential mineral and energy resources within prospective deep-sea areas. It also includes advice on developing an environmental baseline for future environmental impact assessment. The new understanding of mineral and energy resources presented here greatly expands Chile's position beyond that as a source of terrestrial minerals to include potentially vast marine-based energy and metal resources, which are highly valued by industry. Based on these considerations, we encourage decision makers to promote and support studying marine deposits to further protect and evaluate future exploration. [Display omitted] [ABSTRACT FROM AUTHOR]

Mainland China has the most complex continental tectonics on Earth, making it one of the ideal laboratories for probing the tectonics and evolution of the Earth. However, no consensus has been reached regarding the basement tectonic architectures and evolution of mainland China. This paper focuses on the interpretation of aeromagnetic and seismic refraction data, closely incorporating available surface geological data, borehole data, and seismic data to trace the likely occurrences of oceanic plateau slices in the basement architecture of mainland China. We suggest that the highly positive aeromagnetic anomalies and thick high-velocity lower crustal layer indicate that the Junggar basin is floored by an oceanic plateau. The Tarim basin can be divided into a southeastern oceanic plateau block with strongly positive aeromagnetic anomalies and a northwestern passive continental margin block with weak aeromagnetic anomalies. Both blocks got amalgamated together during the late Paleoproterozoic, and the irregular, promiscuous aeromagnetic anomalies within the northwestern block are spatially consistent with and attributed genetically to the Tarim Large Igneous Province (LIP). The lower crust of the Qaidam basin is characterized by large P-wave velocity, suggesting that the basin is floored by an Early Paleozoic oceanic plateau, and the deep-seated subduction of the oceanic plateau could be responsible for the ultrahigh-pressure (UHP) metamorphism in the northern Qaidam margin during the Early Paleozoic. The western North China craton could be an assembly of multiple oceanic plateau fragments along irregular continental margins during the Paleoproterozoic. An intraplate suture (Miaowan suture) divides the Yangtze craton kernel to the east and the Shennong terrane to the west; both were amalgamated during the Neoproterozoic. The Yangtze craton kernel could be floored by an oceanic plateau basement characterized by large P-wave velocity and strongly positive aeromagnetic anomalies. All these oceanic plateau basements exhibit strong rigidity to resist later tectonic deformation and generally remain intact. • Junggar basin is floored by oceanic plateau of highly positive magnetic anomalies 3 and high velocity • Tarim basin is divided into northeastern oceanic plateau and southwestern passive 5 margin. • Qaidam basin is floored by oceanic plateau, whose subduction resulted in UHPM 7 in N. Qaidam margin • Western North China craton is an assembly of oceanic plateaus during the 9 Paleoproterozoic • Yangtze craton kernel is floored by oceanic plateau and divided by Miaowan suture 11 from Shennong terrane. [ABSTRACT FROM AUTHOR]

Greenhouse gas emissions have led to severe global climate change, and countries around the world are taking measures to mitigate the greenhouse effect caused by carbon emissions. Carbon dioxide capture, utilization and storage (CCUS) is emerging as a large-scale greenhouse gas emission reduction technology and can potentially become an important means to mitigate the greenhouse effect in the future. There are a series of problems in the implementation of this technology, among which the geomechanical problems due to the thermal effect should not be neglected. This paper summarizes the non-isothermal processes in CCUS and the impacts and hazards caused by the thermal effects of non-isothermal processes. We show that CO 2 injection and sequestration will experience heat exchange with high-temperature formations and wellbores, exothermic dissolution, cooling by the Joule–Thomson effect, exothermic adsorption and exothermic hydrate formation when CO 2 replaces CH 4. These non-isothermal processes can lead to risks including reservoir stability, fault activation and induced seismicity. Thermal effects can also alter reservoir characteristics, such as the effect on CO 2 injection and storage efficiency. This work presents the challenges and future perspectives of thermodynamic studies in CCUS, which will help to fully understand the thermal effects and risks in CCUS and provide a reference for future CCUS operation, monitoring, and research. [ABSTRACT FROM AUTHOR]

The nature, extension, and evolution of the Meso-Tethys still remain unclear to researchers, and this has thereby hindered in-depth study of the Tethys tectonic domain. In this paper, we review the geology of the Tethys tectonic domain and suggest that the Meso-Tethys is a massive tectonic zone divided into three segments. The central segment includes the Bangong-Nujiang Suture Zone on the Tibetan Plateau and the Shyok Suture Zone in the South Pamir Mountains. This segment has been well studied and is the key link that fully records the birth, evolution, and demise of the Meso-Tethys Ocean from the Permian to Cretaceous, as well as the subsequent continental collision and crustal uplift. The western segment includes the Sanandaj-Sirjan Suture Zone and the Izmir-Ankara-Erzincan Suture Zone in the Middle East. Due to limited research on the western segment, our understanding of it is mainly derived from records of the Jurassic forearc extension,development of arc, and subsequent arc-continent collision. The eastern segment includes the Shan Boundary in Southeast Asia. It has received widespread attention in recent years, and it contains complete records of the Jurassic subduction of the Meso-Tethys Ocean. Based on the latest comprehensive data, we propose that the evolution of the Meso-Tethys Ocean can be divided into four stages: (1) the Early Permian rifting and opening stage; (2) the Middle Permian-Triassic seafoor spreading stage; (3) the Late Triassic-Jurassic convergence stage; and (4) the Late Jurassic-Early Cretaceous diachronous closure from east to west in the central segment and transition from the Meso-Tethys evolution to the Neo-Tethys evolution in both the eastern and western segments. The Meso-Tethys Ocean underwent complex evolution for at least ∼160 Myrs. It has an east-west length of over 8000 km and a maximum north-south width of close to 5000 km during the Late Triassic, which basically reached the scale of the current Indian Ocean. It was an important ocean basin that coexisted with the Paleo- and Neo-Tethys oceans, a key intermediate link in the evolution of the Tethys, and one of the major contributors to the continuous disintegration of Gondwana and the accretion of the Eurasian continent. Its complex evolution process and multiple periods of accretion resulted in the formation of complex geological records and the wide scale of the Meso-Tethys (e.g., the Bangong-Nujiang Suture Zone), making this area a rare natural laboratory for in-depth study of orogenesis, which is of great significance for studying tectonic processes on the global scale from seafloor geology to continental accretion and mineralization. [ABSTRACT FROM AUTHOR]

Hyperspectral remote sensing (HRS) has emerged as a promising technique for monitoring the spatiotemporal distribution of soil heavy metal (SHM) contamination, owing to its extensive coverage and high-efficiency. Nevertheless, the monitoring technique for SHMs based on HRS still faces challenges in engineering applications, including the unclear theoretical basis, unstable inversion methods, and uncertain application scenarios for remote sensing platforms. In this paper, we conducted a comprehensive review of 529 critical publications to identify research gaps and uncertainties related to this monitoring technique. Firstly, the theoretical basis of SHM monitoring is elucidated, highlighting the crucial role played by the association characteristics between soil active ingredients (SAIs) and SHMs as the core theoretical support for SHM inversion. Subsequently, we systematically review the current state of research on key steps in the monitoring technique, encompassing spectral pre-processing, spectral characteristic identification, and inversion modeling. This is because the application results of these steps often lack uniformity or even exhibit contradictions. Notably, the results show that representative characteristic bands, despite being identified within the wavelength ranges of 400–1000, 1200–1450, and 1700–2400 nm, exhibit significant variations across different SHMs and application scenarios. Machine learning methods (R2: 0.54–0.94) employed in SHM inversion modeling are not significantly superior to empirical statistical models (R2: 0.52–0.91). Moreover, the historical development survey of remote sensing platforms indicates the increasing utilization of airborne and spaceborne HRS platforms, particularly HyMAP and GF-5, for SHM monitoring. However, achieving a balance between monitoring accuracy and breadth remains a fundamental challenge for each HRS platform. We recommend emphasizing research directions of this monitoring technique around the guidance framework of "mechanism-data-model-application", thereby effectively aiding in the prevention and control of SHM contamination in the future. [Display omitted] • Correlation between SAIs and SHMs is core theoretical basis for SHM inversion. • Key characteristic bands of SHMs in diverse scenarios were summarized. • SHM inversion accuracy is comparable for machine learning and statistical models. • High-accuracy, large-scale SHM monitoring needs space-air-ground spectral fusion. • Future research focuses on "mechanism-data-model-application" framework. [ABSTRACT FROM AUTHOR]

This paper presents a review of the trends and geographic variation of impacts of reactive nitrogen (N) inputs on in Europe through impacts on air, soil and water quality. It illustrates those impacts, by assessing temporal and spatial variation in air, soil and water quality indicators and their exceedances of critical thresholds in view of impacts on human health, terrestrial and aquatic ecosystems, during 1990-2019. Trends are derived from regular inventory and monitoring data and from simulated trends in air quality using the EMEP model. Well quantified adverse impacts of increased N use are: (i) the effects on human health due to increased tropospheric concentrations of NO x and ozone, and N-induced increases in fine particulate matter, (ii) the contribution of N 2 O to climate change and stratospheric ozone depletion, (iii) the loss of plant and faunal diversity both in terrestrial and aquatic ecosystems via direct and soil mediated impacts, (iv) the acidification of forest soils, with impacts on tree forest nutrition, tree growth and tree vitality, and (v) the eutrophication of marine ecosystems, and associated biodiversity loss and occurrence of harmful algae blooms. Over the period 1990-2019, N inputs to agriculture stayed relatively constant, but the emissions of ammonia (NH 3) decreased by 27%, while emissions of nitrogen oxides (NO x) decreased by 57%. In response to those reductions, concentrations of NO x , and of N in particulate matter also declined, although less than 50%. In contrast, the reduction in NO x -induced ozone concentrations and ozone related indicators (AOT40, SOMO35 and POD) was much less (ca 15-20%). Exceedances of critical ozone concentrations for human health and of critical AOT40 and POD vales for vegetation reduced in a similar order of magnitude. Despite decreasing NH 3 emissions, NH 3 concentrations showed a slight and steady increase from 1995 onwards, due to the large reduction in SO x emissions. Nitrogen deposition and exceedances of critical N loads for terrestrial ecosystems decreased by ca 60%, but the area exceeding critical N loads only reduced by ca 10%. Unlike N, the area exceeding critical acid loads has declined by more than 90% due to high reduction in SO x and NO x emissions. Trends in nitrate (NO 3) concentrations in groundwater varied across Europe, but showed overall limited changes over the last two decades. However, N concentrations in surface water and the area exceeding critical levels in view of aquatic biodiversity has decreased and the same holds for N concentrations in coastal regions. Nevertheless, the eutrophication condition of coastal waters has overall not improved due to adverse impacts of elevated phosphorus inputs. Finally the negative impacts of N induced N 2 O emissions on climate are estimated to be outweighed by the positive effects of N induced CO 2 sequestration, mainly in forests, and this holds for the whole period 1990-2019. Nitrogen hotspots, being areas with high exceedances in critical levels and loads of N compounds in air and water, are concentrated in intensive agricultural areas with high livestock densities and in urban region with strong industrial and traffic activities. Cost-benefit analysis shows that environmental costs of reactive N release to the environment are substantial and tend to exceed the direct economic benefits for agriculture. Given the relevance of N for safeguarding food production it is key to develop integrated and targeted plant nutrition strategies following a food system approach and practices that minimize trade-offs between productivity and the environment. In addition, targeted strategies to further reduce NO x emissions are needed to reduce air quality related health and biodiversity impacts. • Adverse impacts of reactive nitrogen are most evident for human health and for aquatic and terrestrial ecosystems. • Effects of nitrous oxide emissions on climate are largely counteracted by N induced carbon sequestration. • Ecosystem restoration in response to declined N inputs in Europe since 1995 shows a time lag. • There is large spatial variation across Europe in N impacts, requiring regional policies. • Environmental costs of reactive nitrogen varied from 0.4 to 6.8 euro per kg N. [ABSTRACT FROM AUTHOR]

Alkaline lakes are significant for exploring the evolution of life, reconstructions of environments, and exploration and exploitation of energy resources; however, despite modern alkaline lakes being widely distributed on Earth, deep-time (pre-Neogene) examples are scarce, in general, compared with other types of saline lake deposits (e.g., chloride and sulfate salts). This raises the question as to whether this scarcity is due to their extreme formation conditions or because they have yet to be discovered, owing to the difficulty in identification of these deep-time lakes. This paper addresses this question by analyzing the distribution and formation mechanisms of modern alkaline lakes in order to interpret the past based on the present. These results indicate that alkaline lakes can be identified from the presence of alkali minerals, such as trona and nahcolite, and heavy N isotopes (>10‰) caused by NH 3 volatilization. Modern alkaline lakes can be classified into two main types, including those in tectonically active and inland arid zones. Their formation mechanisms are controlled by multiple factors, such as a (semi-)closed basin geography, (semi-)arid climate that favors high degrees of evaporation, and the presence of strongly alkaline fluids that are rich in HCO 3 − and CO 3 2−. The formation mechanisms of discovered deep-time alkaline lakes are similar to those of modern examples. The δ13C, and δ18O of carbonates, Mg/Ca, chemical index of alteration, and chemical index of weathering indicate that deep-time alkaline lakes were also generally deposited in (semi-)closed basins with a (semi-)arid climate, which were conducive to strong evaporation and concentration of saline waters. Furthermore, chemical weathering and hydrolysis of silicate minerals, volcanic–hydrothermal activity and circulation of basinal brines, and microbially mediated processes also produced alkaline fluids rich in HCO 3 − and CO 3 2− necessary for the formation of ancient alkaline lakes. Alkaline lakes should be widespread throughout geological history, but may be poorly preserved in old stratigraphic sequences or difficultly in identification because of their limited outcrop and depth. Future studies of evaporite mineralogy and the N isotope geochemistry of ancient saline lacustrine basins are necessary to further our understanding of their identification and formation mechanisms. Such studies should also investigate the favorable development zones, characteristics of organic matter accumulation, astrobiology, etc. [ABSTRACT FROM AUTHOR]

Desertification in karst is an effect of climate change and not sustainable anthropogenic activities, the combination of which, however, causes the gradual loss of karst natural resources, such as soil, vegetation, and groundwater. A considerable percentage of global karst areas is found in drylands, characterized by negative water balance and scarce presence of soils. High fragility of the karst environment, and its vulnerability to land degradation and pollution because of the peculiar anisotropic setting, environmental dynamics, and of the direct connection between the surface and the subsurface, are at the origin of the severe problems deriving from desertification processes in karst. In addition to natural drivers, such as geology and topography, karst desertification is generally due to four main factors, mostly or partly related to human activity: deforestation, improper land use, groundwater overexploitation, and climate changes. Through the analysis of a collection of studies conducted in several karst territories around the world, the present paper aims to provide an overview of the processes leading to desertification risks in karst areas. Emphasizing the need to preserve these fragile environments, characterized by peculiar features and precious freshwater resources, this review summarizes the main situations at the global scale of rocky desertification in karst, at the same time providing indications for developing innovative and multi-disciplinary approaches addressed toward mitigation of the risk related to desertification in karst. [ABSTRACT FROM AUTHOR]

The gravitational field of the Earth reflects Earth's surface mass redistribution and its inner structure and dynamics. Satellite gravimetry techniques have been used to observe the Earth's external gravitational field and its temporal variations on a global scale. The global gravitational models from satellite gravimetry, typically in terms of spherical harmonic coefficients, are crucial in geodetic, geodynamic, geophysical, hydrological, glaciological, oceanographic, and many other geoscience applications. In this paper, we provide a comprehensive overview of theoretical definitions describing relationships between the spherical harmonic coefficients and different satellite gravimetry observables such as orbital perturbations in terms of satellite positions, velocities, and accelerations; satellite-to-satellite range rates; and gravitational gradients. Products and applications of the Earth's static global gravitational models are presented and discussed in the context of determination of the gravimetric geoid and physical heights, gravimetric and isostatic crustal thickness, bathymetric depths, glacier bedrock relief, sediment thickness, geostrophic and eddy currents, Earth's inertia tensor and dipole, precession and nutation parameters of the Earth's rotation, and prediction of the satellite orbital geometry. Furthermore, applications and advances of the Earth's time-variable gravitational models for monitoring large earthquakes, hydrological mass transport, Earth's rotation parameters, and vertical crustal motions (due to the glacial isostatic adjustment and other phenomena) are presented. Finally, future trends and prospects in the satellite gravimetry are discussed. • A comprehensive mathematical foundations of satellite gravimetry is presented. • A complete progress for applications of satellite gravimetry products is shown. • An overview for future satellite gravimetry missions and trend is given. [ABSTRACT FROM AUTHOR]

The offshore margins of Guyana, Suriname, and French Guyana (the "Guyanas Equatorial Margin") have become the focus of active hydrocarbon exploration over the last decade, with significant energy resources discovered since 2015 along both the Guyana and Suriname segments of the margin. Those discoveries are mainly associated with the Late Cretaceous series of the Guyana-Suriname Basin and they shed light to a rare situation where stratigraphic traps are particularly successful. To date, the tectono-stratigraphic evolution of the area has been primarily examined at margin-scale through seismic refraction, rare borehole data and sparse, regional long offset multichannel 2D seismic datasets. In this paper we combine the results from newly acquired high-resolution well data, 2D/3D seismic interpretation and 3D seismic geomorphology, to build a robust and consistent sequence stratigraphic framework and address the evolution of Cretaceous sedimentary landscapes offshore Suriname, with a particular emphasis on the Late Cretaceous strata. The Suriname margin displays a very specific overall sequence stratigraphic evolution marked by four main phases each characterized by distinct sedimentary fluxes and related overall geometries: 1) a margin initiation phase, 2) an aggrading phase, 3) a backstepping phase and 4) a forestepping phase. The Suriname basin initiated in the Early/Mid Jurassic after the emplacement of thick Early Jurassic volcanic series attributed to the Sierra-Leone (or Bahamas) Hotspot (phase 1). This localized early magmatic activity led to two very different configurations: a typical Volcanic Passive Margin in the east along the western border of the Demerara Plateau and a transform segment to the west (essentially along the Guyana margin). The following phase (phase 2) is characterized by the establishment of a Late Jurassic to Early Cretaceous mixed clastic‑carbonate platform with an overall aggradational stacking pattern observed until the Early Aptian. Phase 3 started by significant backstepping, that culminated during the Cenomanian-Turonian transition, coeval with widespread organic-rich marine shale deposition. This overall transgression occurred in four steps: (B) late Early Aptian flooding followed by renewed margin progradation; (C) Early Albian flooding and (D) Late Albian to Cenomanian flooding above the break-up unconformity and (E) the maximum backstep at the Cenomanian-Turonian boundary. This long-term transgressive trend is interpreted as the combination of (1) long-term eustatic rise during the early Cretaceous; (2) high rates of margin subsidence following the Aptian to Albian opening phase of the Equatorial Atlantic, and (3) relatively limited sediment supply rates along the margin at that time. The successive, backstepping shelf-margin wedges created a distinctive stepped profile (paleo shelf-margins) that greatly impacted the geometries of the overlying Late Cretaceous sequences. During this backstepping phase, clastic sediment delivery to the deep-water part of the Suriname basin in the Early Cretaceous was limited and mainly sourced from the large Berbice Canyon complex at the Guyana-Suriname border. The outlet of the Berbice drainage systems may have been anchored by an aborted section of the Jurassic rift and linked to the onshore Takutu graben which separates the Guyana shield in two parts. The fourth phase of the Jurassic to Cretaceous evolution of the Suriname margin is characterized by a dramatic increase of the sediment supply during the Santonian resulting in the accumulation of thick sequences of channel-dominated turbidite fans. This renewed clastic input is linked to a major drainage reorganization on the Guyana shield and is also coeval to the change from the point-sourced Berbice system to a line-sourced input from smaller rivers and deltas along the Suriname margin. From Early Santonian to Late Maastrichtian, the offshore sedimentary systems were then characterized by an overall regression with stacked coastal clastic systems on the shelf and continued fan deposition in the slope together with abundant slope erosion and related Mass Transport Complexes. At higher frequency this long-term forestepping Late Cretaceous trend was modulated by accelerated pulses of sediment supply (and associated margin progradation) during the Middle Santonian, Middle Campanian, and the Early Maastrichtian. From the Santonian turn-around to the Late Maastrichtian, sedimentary systems are deciphered as sequences constrained by biostratigraphic data from the latest industry wells in Block 58 in Suriname and combined with seismic interpretation of both 3D and 2D data. The multi-scale sequence stratigraphic framework built in this study highlights 1) the specific sedimentary architecture of the margin and 2) the role and the impact of external forcing on the sedimentation rate. Moreover, the results highlight the key importance of topographic inheritance (from both structural and sedimentary origin) on deep-water reservoir architecture, that led to important hydrocarbon accumulations through stratigraphic trapping in offshore Suriname. [ABSTRACT FROM AUTHOR]

Accurate flood mapping is crucial for enhancing community resilience in the face of flooding. Among the several factors that affect the flood extent, the effect of fluvial dynamics is not clearly recognized so far. Fluvial dynamics play an important role in shaping the patterns and magnitudes of water flow and sediment transport in riverine environments, that consequently affect flood extent. By conducting a scoping review, this paper aims to show how the river's hydrological processes and channel morphology impact floods and flood mapping. To do that, previous studies dealing with flood modeling have been explored to provide a comprehensive understanding of the interactions between fluvial dynamics and flood mapping outcomes. The results showed that morphodynamic variations and sediment transport impact flooding differently depending on local morphological conditions. Some studies indicate that these processes can increase the likelihood of flooding, potentially posing greater risks to nearby areas. Conversely, other research suggests that these morphodynamic variations may help reduce flood occurrences, signaling a nuanced relationship between river morphology and flood dynamics. Additionally, it was found that while bed-load movements significantly influence the synchronization of peak water surface elevation and peak flow times, suspended sediment concentration has minimal impact on the timing and shape of the hydrograph. The results emphasize the crucial role of integrating fluvial hydro-morphodynamics into flood mapping to enhance flood management in riverine environments, contributing to both increased resilience and broader sustainable development goals. [Display omitted] • The influence of sediment dynamics and channel morphology on floods is reviewed. • Sediment impacts flooding differently depending on local morphological conditions. • The findings stress the need to include sediment dynamics in flood studies. [ABSTRACT FROM AUTHOR]

The general configuration of the main continental blocks in the Gondwana supercontinent and the Ediacaran–early Paleozoic tectonic evolution of its northern margin are widely accepted. However, reconstruction of the original positions and the question of potential separation of the Gondwana-derived crustal segments that are now included in the Variscan and Alpine orogenic belts remain controversial. The Western Carpathians, part of the Alpine–Carpathian belt, represents an important crustal segment broken-off from northern Gondwana and later incorporated into both the Variscan and Alpine collisional orogens. The earliest tectonic evolution and paleogeography of the pre-Variscan basement of the Western Carpathians remains poorly known, due to insufficient age data and intense polyphase tectonometamorphic overprints, both Variscan and Alpine. This paper provides new results of U–Pb dating and Hf isotopic analysis of detrital zircons as well as a whole-rock geochemical study from metavolcanic-sedimentary basement units of the Western Carpathians. The obtained age spectra suggest that the sedimentary succession was supplied dominantly by Ediacaran (c. 600 Ma) zircons, with a relatively minor role for Stenian–Tonian (c. 1.2–0.9 Ga) and Paleoproterozoic cratonic (c. 2.2–1.8 Ga) zircons. The mixed Hf isotopic signature (ε Hf(t) values ranging from −20 to +12) of the Ediacaran zircons indicates substantial mixing of mantle-derived magmas with mature crustal material, typical of continental magmatic arcs. In contrast, the mostly negative ε Hf(t) values (−15 to +4) of the cratonic zircons suggest recycling of an older continental crust. The presumably youngest part of the sequence is also characterised by high proportion of early Paleozoic zircons with generally negative ε Hf(t) values (−10 to −2). The zircon U–Pb age spectra, Hf isotopic patterns and whole-rock geochemical signatures of the studied Western Carpathians sequences are interpreted as reflecting deposition at a progressively developing Cambrian–Silurian passive margin setting. The West Carpathian data have been correlated with a comprehensive detrital zircon U–Pb age and Hf isotope data set compiled from possible source areas and other Gondwana-derived units to test the possibility of their primary linkages. These correlations indicate strong similarity in both zircon U–Pb age spectra and Hf isotopic compositions to other parts of the Ediacaran (Cadomian) continental magmatic arc. Older, cratonic sources are linked to the Saharan or East African parts of northern Gondwana, whereas the early Paleozoic detritus must represent a local volcanic source. Taken together, our new data from the Western Carpathians provide constraints for a new paleogeographic model of the northern African part of the Gondwana passive margin. • Cambrian–Silurian formation of Western Carpathians in the Gondwana passive margin. • Detrital zircon ages and Hf isotopic data record temporal variations in sources. • Affinity of the Western Carpathians to the central Saharan segment of Gondwana. • Provenance shift from the Saharan province to the East African province. • New paleogeographic reconstruction of the African part of Gondwana margin. [ABSTRACT FROM AUTHOR]

The Mesozoic tectonic regime of the Indonesian Archipelago holds the key to decoding the development of the East Asia continental margin and unraveling the temporal-spatial pattern of the Paleo-Pacific and Tethyan supra-subduction systems in SE Asia. However, no consensus has been reached on the "intersected location (where), timing (when) and mechanism (why)" of the two supra-systems in the "narrow knot zone". This paper presents an overview of key geological observations in Borneo and its surrounding areas in the heart of the Indonesian Archipelago with respect to its Mesozoic tectonics. Available data collectively show that the western segment of west Borneo, along with west Sumatra, have Sundaland affinities, representing the southernmost segment of the Paleo-Tethyan active continental margin. West Borneo was overprinted by the Paleo-Pacific-related accretionary orogenesis in the Jurassic and Cretaceous periods. The Mesozoic rock-units in Sabah (NE Borneo) exhibit Cathaysia-like affinities and their generation in an earliest Triassic-Late Jurassic arc-trench gap setting. The Mesozoic igneous rocks in NE, NW and SW Borneo define magmatic flare-ups at ca. 190 Ma, ca. 150 Ma, ca. 130 Ma and ca. 85 Ma that are comparable to those in Coastal South China. This magmatic activity represents a long-lived active continental margin derived by the pulsed Paleo-Pacific subduction and rollback. This oceanwardly-propagating accretionary orogen extends from the Lupar-Palangkaraya of west Borneo into Coastal South China, and extends as far as the Russian Far East via SE Vietnam and Sabah (NE Borneo)-Palawan (Philippine) arc-trench system. In NW and SW Borneo, the Jurassic and Cretaceous arc-like igneous rocks, whether mafic-intermediate or felsic, mostly share similar Sr-Nd-Hf-O and Pacific-like Pb isotopic compositions, which originated from the subduction-related mantle wedge or its juvenile crust source in a convergent plate margin setting. All the data indicate that Paleo-Pacific subduction had at least initiated by the earliest Triassic in NE Borneo and likely Coastal South China, and earliest Jurassic in NW and SW Borneo, but likely ceased at ca. 80 Ma. SE Borneo represented the easternmost segment of the Neo-Tethyan Ocean, along which northward subduction initiated at ca. 140 Ma and ceased at ca. 90 Ma. Such a Neo-Tethyan subduction system was cold and rapid, and was followed by the rapid exhumation at ca. 133–110 Ma along the Central Indonesian Accretionary Collision Complex as defined by the presence of HP/LT clockwise P-T-t metamorphism. Tectonic overprinting in East Asia since the Late Cretaceous might have driven the twist of the Paleo-Tethyan tectonic zone in west Sumatra and the intersection of the Paleo-Pacific and Neo-Tethyan systems in the Palangkaraya area between SW and SE Borneo. The Mesozoic stratigraphic framework is herein updated but validation will be required in the future. Integrating all available observations, and uncertainties a tectonic model is reconstructed for the interaction of Paleo-Pacific and Tethyan supra-subduction systems in SE Asia from the Triassic to Cretaceous. [ABSTRACT FROM AUTHOR]

The vadose zone serves as a crucial link for the mutual transformation of atmospheric, surface, ecological, and groundwater systems. Infiltration recharge in the vadose zone is a key step in the Earth's water cycle and plays an extremely important role in the sustainable development of groundwater resources, particularly in arid and semi-arid regions. However, under the influence of extreme climatic conditions and intense human activity, the vadose zone has thickened in many places globally. Changes in the vadose zone structure lead to alterations in the infiltration process. Researchers have attempted to quantify this process using various methods. However, it has been found that conventional monitoring methods are inadequate to effectively describe the complex infiltration recharge process under the multifactorial influence of a deep vadose zone. Through an analysis of relevant literature published from 2000 to 2023 regarding deep vadose zone infiltration recharge, this paper identifies four contentious bottlenecks: (1) effective monitoring and simulation of deep vadose zone infiltration recharge, (2) modes of deep infiltration recharge, (3) issues related to the quantity and recharge period of precipitation and irrigation infiltration recharge, and (4) quantification of spatial variations and scale effects of infiltration recharge. After reviewing the latest developments in infiltration recharge monitoring and simulation and systematically analyzing the influencing factors and mechanisms of deep vadose zone infiltration recharge, this study provides answers to the aforementioned issues. The combined use of monitoring and numerical simulation methods, taking into account infiltration recharge scenarios and scales, can enhance the reliability and accuracy of the calculation results. Additionally, piston flow may not be the primary mode of water movement in the deep vadose zones. Understanding the modes and characteristics of water movement, as well as the differences in suction and desorption processes, is fundamental for accurately describing nonlinear infiltration recharge processes. Furthermore, the measured average vertical infiltration rates of the deep vadose zone vary widely from 0.14 to 500 mm/d globally. In the North China Plain, vertical infiltration recharge rates range from 133 to 300 mm/a. These significant differences are related to the research scale, external conditions, and internal soil structure within the vadose zone. Finally, a systematic analysis of the driving factors of nonlinear infiltration recharge in the deep vadose zone is a prerequisite for quantifying spatial variations and scale effects. Only by fully considering the interactions and contributions of various driving factors can the spatiotemporal variations in soil infiltration be effectively quantified. Therefore, our research team suggests that future studies on deep vadose zone infiltration recharge should focus on establishing a unified layout for large-scale, multi-point, synchronous, in situ, and long-term monitoring; constructing relationships between the vadose zone structure and hydraulic characteristics; and conducting comprehensive studies on the overall water cycle in the Earth's surface layers, with the deep vadose zone as the core. These will help build a research system for the spatiotemporal infiltration recharge of water in the deep vadose zone at multiple layers and scales, achieving the closest approximation to a realistic description of the deep vadose zone infiltration recharge. [ABSTRACT FROM AUTHOR]

To settle in a given area, man has to deal with the surrounding environment and the geomorphological processes that shaped it. Landscape defines the available resources and landscape changes are related to tectonics, hydrography and variations in climate and biota. To cope with environmental limitations, man developed efficient techniques and capabilities to survive, making the best use of natural resources. The Fars arc (southern Iran) is known for being the cradle of some of the earliest civilizations in Iran. It comprehends the southeastern sector of the Zagros Mountains, a Cenozoic orogen formed after the collision between Arabia and central Iran. The landscape is dominated by a series of folding structures which isolate internal basins. This configuration, together with arid climate conditions, limited biological resources, and the occurrence of natural disasters such as earthquakes, floods, landslides, water salinity, biological/climatic changes and droughts, all dictated the development and pattern of human settlements. This paper aims to give a broad overview on the deep influence exerted by geomorphological processes, such as tectonics, earthquakes, landslides, sea level fluctuations, and climate changes, on the emergence and development of human settlements in the Fars arc which, with its long-lasting and documented civilization history, represents an ideal test site to study the interaction between nature and man. [ABSTRACT FROM AUTHOR]

In this review paper, the main geometrical characteristics of sea ripples (the smallest morphological patterns that are observed at the bottom of sea waves) are reviewed together with the physical mechanisms that give rise to their appearance and control their time development. Moreover, we provide a summary of both the mathematical tools (stability analyses) and empirical formulae that can be used to predict their appearance and some of their geometrical characteristics. The ripples play a relevant role in the mechanics of coastal sediment transport since usually the flow separates at the ripple crests and generates vortex structures that pick-up the sediments from the bottom and put them into suspension. Moreover, the vortex structures shed by the ripples significantly affect wave damping and flow resistance. [ABSTRACT FROM AUTHOR]

A marginal snowpack is a recent concept that refers to snow cover that is relatively shallow and transient but still has important environmental and socioeconomic functions. This class of snow cover influences environments over large areas of the world and is very common in the Mediterranean climates, but also in the transition zone between persistent seasonal and ephemeral snowpacks all over the world. However, a globally-accepted definition to identify these environments has not been reached yet. Most of the modelling and monitoring tools for snow have been developed in cold and alpine areas with persistent snowpacks. The study and modelling of shallower snowpacks in milder environments are complicated by their high temporal variability, frequently patchy nature and typical coexistence with shrubs and forest. However, in recent years new remote sensing tools and more complex modelling approaches and specific parametrizations are facilitating their study. This paper provides a definition for marginal snowpacks, identifying them as those with: (i) seasonal peak depths that only occasionally surpass 1.5 m in favorable deposition zones such as wind drifts, ii) having typical seasonal durations ranging from 60 to 120 days, and (iii) that are predominantly in an isothermal state (on >75% of days) with high densification rates and several cycles of accumulation-ablation during each snow season. We review the main existing research challenges to improve scientific capabilities for their study and we discuss their hydrological and environmental relevance at different spatial scales. [ABSTRACT FROM AUTHOR]

Water erosion, a notorious major threat to food security and ecosystem sustainability, is strongly conditioned by spatial and temporal scale effects. This paper systematically reviews the scale issues in runoff and sediment delivery (SIRSD) as a research field by integrating the traditional review approach and bibliometric analysis. This review summarises SIRSD's roots and the scale effect on runoff and sediment delivery. Then, we provide quantitative insights into the SIRSD domain's development history, thematic structure, geographic distribution, international cooperation, and methodologies. Findings show that: i) SIRSD arises from the gap between the non-linearity of runoff and sediment delivery across scales and our ability to measure it. Point-based and short-term measurements cannot capture the non-linearities from the spatio-temporal heterogeneities and cross-scale interactions of factors or processes. ii) Previous literature provides evidence that the spatial scaling of specific runoff (r), soil erosion (SE), sediment yield (SSY), or sediment delivery ratio (SDR) with drainage area (A) or slope length (L) exhibits contrasting patterns due to distinct mechanisms. Infiltration-excess and saturation-excess processes account for inverse and positive r - A relations, respectively. Interrill-erosion and rill-erosion cause inverse and positive SE-L relations. Hillslope-erosion and channel/bank-erosion explain inverse and positive SSY-A relations. Downstream increasing deposition and additional sediment inputs drive inverse and positive SDR-A relations. These scaling relationships can be nonlinear or complex due to spatial heterogeneities in land use, vegetation, topography, climate, lithology, and soil characteristics. Hence, applying an empirical scaling equation developed from the region with distinct environmental contexts is not recommended. Furthermore, the existing scaling patterns or equations may require updating given global climate and land use change. iii) SIRSD is a complex and multidisciplinary issue investigated by scientists from 93 countries since 1928. International research has substantially facilitated the understanding of SIRSD; still, more collaboration should focus on less-developed countries with high soil and water loss risks and urgent conservation needs, such as those in Africa and South America under cropland expansion. iv) Scale mismatch and scale break have discredited large-scale erosion and sediment assessments. Incorporating gully and bank erosion into modelling, extending the scale range of the L factor, and expanding the sediment scaling scope from watershed to slope may make a difference. Therefore, more research with nested design incorporating multiple scales is necessary for cross-scale analysis and scalable modelling. Addressing global climate change requires improving real-time urban flood forecasting and integrating downscaled climate models with hydrology, erosion, and sediment transport models. • A bibliometric review of the global SIRSD research for the first time. • SIRSD is rooted in the gap between natural nonlinearity and our measuring ability. • Scaling of specific runoff, erosion, sediment yield, and SDR has diverse patterns. • Scale mismatch and scale break discredit large-scale modelling and assessments. [ABSTRACT FROM AUTHOR]

This paper explores the formation and evolution of high-elevation passive margins, focusing on the morphology and uplift processes of the eastern Red Sea region and its relationship to the stratigraphy of the Red Sea (source-to-sink approach). We address gaps in our understanding of the origin and persistence of erosional escarpments along rifted margins and their connection to continental rifting. To achieve this, the research combines geological observations, geomorphic mapping and reconstructions of past topography to estimate erosion and compare it to accumulated sediment volumes in the basins. The study presents a landform map and an age model of landscape evolution of the Eastern Red Sea Rifted Margin (ERSRM), identifying 4 phases of erosion affecting two separate domains. On the Arabian plateau, remnants of the African surface (S I) and an Oligocene planation surface (S II) were rifted, uplifted and exhumed during rifting, and refreshed (S III) since the onset of seafloor spreading. West of the escarpment, a young (< 15 Ma) foothill belt (S IV) was carved by the eastward retreat of the Arabian Escarpment. We identified three different settings controlling the escarpment evolution and coastal plain morphology along the margin from north to south: (1) escarpment retreat from the rift fault towards the interior in the northernmost Red Sea, (2) escarpment retreat synchronously from two parallel rift faults and capture of a former endorheic drainage system, resulting in the formation of the biggest catchment in western Saudi Arabia (i.e., Wadi Hamd), and (3), escarpment retreat within a downwarped margin in the southern Red Sea, accompanied by sustained flexural uplift. These settings are the result of rift inherited structures segmenting the Red Sea, as well as the effect of the AFAR hotspot fading towards the north around the Jeddah latitude. Furthermore, we demonstrate that the escarpment evolution was not a steady process, as at the end of rifting ∼16 million years ago, erosion rates were high and remain relatively high (although decreasing) up to 5 million years. Then a dramatic drop in erosion rates occurred, documenting the cessation of the escarpment retreat. We link this decrease in erosion and sedimentation rates to a global aridification of the climate throughout the Plio-Pleistocene. Finally, we discuss the complexity of escarpment evolution, both in terms of time and space, mitigating the often simplified vision of linear escarpment evolution. By bridging the gap between onshore geomorphic evolution and coastal basin stratigraphy, this study contributes to a comprehensive understanding of the long-term evolution of rifted margins. [ABSTRACT FROM AUTHOR]

Radon can pose a serious risk on human health. At present, radon has been considered as the second leading cause of lung cancer after smoking. The potential risk of radon exposure in cold regions of Northern Hemisphere is increasing due to climate-induced permafrost degradation. In this paper, we took permafrost regions in the Northern Hemisphere as our study area. We performed an extensive literature review on the Web of Science (WoS), China National Knowledge Infrastructure (CNKI), and Google Scholar (GS). We divided these selected literatures into three groups: Group uranium, Group radon and Group permafrost and tried to reveal the impacts of distribution of uranium deposits/u-rich rocks and permafrost/permafrost degradation on radon concentration/migration in permafrost regions. Based our research, it is evident that uranium deposits or U-rich rocks provides an abundant source of U (Ra) for soils and groundwaters in permafrost regions, resulting in abnormally high concentrations of radioactive elements in soils and groundwaters. As a natural barrier, permafrost soils could screen the radon gas from migrating into underground dwellings and work-space in cold regions. However, permafrost degradation has been extensively observed and this trend is projected to continue under a warming climate. Permafrost degradation and ground ice melting, water exchange, gas emissions and thaw settlement have enhanced the ability of radon migration into dwellings and work space, which substantially endangers human health if long exposed. Our synthesis results also underline that the related research of radon migration and relation in permafrost regions are grossly inadequate and urgently needed. Research priorities include the mechanisms of radon migration in freezing, frozen, thawing and thawed soils/rocks, responses of release of radon sequestered in permafrost soils and radon migration in groundwater systems, among many others, to permafrost degradation. [ABSTRACT FROM AUTHOR]

Based on the systematic summary and analysis of a large number of relevant literatures, combined with the authors' related research findings, some new insights are presented on the relation between the valid interval of the Kaiser effect and the characteristic stresses of rocks. The acoustic emission activity of rocks exhibits a sudden increase when the largest previously experienced stress is exceeded during reloading, which is known as the Kaiser effect. The Kaiser effect has been widely used as one of the core-based methods to determine in-situ stress due to cheap, easy and less time consuming. However, the Kaiser effect is influenced by various factors, such as previous damage, rock type and porosity, and the largest previously experienced stress. Nevertheless, a standard method to determine stress has yet to be established due to the lack of a unified understanding of the mechanism concerning Kaiser effect. Since both the Kaiser effect and characteristic stress can be obtained through acoustic emission measurement, particularly in terms of crack initiation stress which is similar to the Kaiser effect stress measurement method. Therefore, it is crucial to conduct a thorough analysis of the relation between the valid interval of Kaiser effect and characteristic stress in order to estimate Kaiser effect stress. This paper provides an overview of the recent investigations that have explored the effect of the above factors on the Kaiser effect and how they can affect the identification of the characteristic stress. The relation between the valid interval of the Kaiser effect and the characteristic stress, which is influenced by the aforementioned factors, was discussed in detail. The valid interval of the Kaiser effect has been proposed in light of the aforementioned research, and corresponding arguments have been presented to support this proposal. These findings can serve as a theoretical foundation for estimating in-situ stress using the Kaiser effect. [ABSTRACT FROM AUTHOR]

Monazite is a light rare earth element (LREE)-rich phosphate mineral that occurs as a trace phase in a wide variety of rock types, where it forms in response to different geological processes from igneous crystallisation, very low- to high-temperature metamorphism, and hydrothermal mineralisation. Monazite is also an ore mineral in some REE-deposits. Owing to its physical and isotopic robustness, high blocking temperature for U-Th-Pb systematics, and widespread occurrence, monazite has become a reliable and versatile geochronometer routinely employed in dating magmatic and higher-grade metamorphic rocks. More recently, it has been increasingly identified in hydrothermal mineral deposits and very low-grade metasedimentary rocks. The ability of monazite to grow at low temperatures can lead to complex age distributions reflecting xenocrystic or detrital grains and multiple episodes of metamorphic or hydrothermal growth. In situ , microbeam analytical techniques, such as SIMS, EPMA and LA-ICP-MS, can provide ages for these low-temperature events. However, textural characterisation and geochemical analysis are required to decipher the petrogenesis of monazite and interpret the meaning of resultant age data. In this paper, we review the petrographic and geochemical characteristics of monazite with well-constrained geological histories, to provide criteria to differentiate monazite that formed in different geological environments. In cases where multiple generations of monazite are present in a sample, differences in chemical composition can often be used as a valuable indicator of origin complementing textural and morphological discrimination. In general, there is a positive correlation between Th contents in monazite and the temperature of the environment in which it crystallised. Magmatic monazite typically contains >3 wt% ThO 2 , as does monazite in high-grade (T > ∼500 °C) metamorphosed rocks. The Th/U ratios of high- T monazites are typically in the range 10–100. Thorium contents of low- T (<350 °C) hydrothermal and metamorphic monazites rarely exceed 3 wt% (mostly <1 wt%, mean 0.6 wt% from data compiled in this study), and their Th/U ratios largely fall between 0.1 and 10. Monazite from carbonatites is characterised by very low U (<30 ppm) and anomalously high Th/U (>300). Thorium content and Th/U ratio of monazite can be used as indicators for distinguishing between low- T metamorphic and hydrothermal, magmatic and high- T metamorphic, and carbonatite-related grains. In comparison with igneous and high- T metamorphic monazites, low- T metamorphic and hydrothermal monazites tend to have depleted Ca and Y, but elevated total REE contents, features which are potentially useful discriminators. On chondrite-normalised REE plots, igneous monazite typically displays a prominent negative Eu anomaly, which is less pronounced in high- T metamorphic monazite. Europium anomalies in low- T metamorphic and hydrothermal monazite range from variably negative in most cases to slightly positive in rare cases. Furthermore, the REE distribution patterns of metamorphic and hydrothermal monazites are widely variable, apparently controlled by compositions of both the fluid phase and the host rock, as well as the P - T conditions under which they formed. The accurate interpretation of monazite age data requires petrographic characterisation combined with high-quality geochemical data. [ABSTRACT FROM AUTHOR]

Loess structure plays a vital role in the evolution of loess landforms, which mainly involves water erosion and slope collapse processes. The existing literature on loess structure lacks a comprehensive and systematic overview covering structural characteristics and features at all relevant spatial scales and explaining how they underlie these processes. This paper presents a detailed discussion of loess structure from this perspective and proposes a structural classification over three contiguous ranges of spatial scales (micro-, meso- and macro-) in terms of nature of particles and pore patterns. Then it details how the initial loess structure is modified by various environmental processes, and outlines cross-scale relations of inheritance among the solid structural elements (microscopic particle assemblies, mesoscopic fragments and macroscopic blocks) and weak segments (pores, channels, pipes, biological pores, abiogenic joints and cracks) making up the present-day loess structure. The ascending impact of ubiquitous micro-scale structure is evidenced by similarity in shapes and spatial arrangement patterns of all features across the scale ranges. Vertically aligned strong units (particle assemblies) coupled with vertically aligned weak segments (pores) defining micro-scale loess structure set the stage for the formation of the structural elements at larger scales. This structure, named as "vertiloess", extends to field-scale landforms (>10 m) bounded and shaped with vertical features throughout the loess plateau. • Comprehensive and systematic overview of loess structure and its evolution. • Scale-based classification of loess structural elements into three ranges. • Cross-scale relations of inheritance among classes and impact on landform evolution. • Meso−/macro-structures in shallow soil layers as scaled-up versions of "vertiloess". • Sorted-out rich resource and firm foundation for future loess studies. [ABSTRACT FROM AUTHOR]

Air-sea turbulent heat flux is vital to the exchange of global water and energy between the atmosphere and the Earth's surface and is essential for understanding Earth-climate mutual feedback. In this paper, we comprehensively review the accuracy and spatiotemporal patterns of 15 global products of air-sea turbulent heat flux from 1988 to 2020. Compared to observations at 139 buoys, all the products overestimate monthly latent heat flux (LHF) and most products overestimate sensible heat flux (SHF), with higher correlation coefficients found for LHF than for SHF. Compared to the reanalysis-based and in situ-based products, the remote sensing-based, machine learning-based, and hybrid-based monthly LHF products are generally more consistent with the buoy observations. The annual mean LHF and SHF values vary greatly between 75 and 115 W/m2 and between 0 and 25 W/m2, respectively. Different products have similar spatial patterns of annual means and interannual variabilities of LHF and SHF in most ocean areas but they have very different magnitudes. Most products show consistent annual trends in LHF and consistent but overall weaker annual trends in SHF, except for in the areas around and beyond 45°S, where larger discrepancies in annual SHF trends are observed. Analogous unimodal shapes of monthly SHF frequency curves from the 15 products are shown in all oceans, but for the monthly LHF frequency curves, both unimodal and bimodal shapes are shown. Seasonal LHF and SHF values are higher (lower) in December–January-February than in June–July-August in the Northern (Southern) Hemisphere. The interseasonal variations in LHF and SHF are more pronounced in the Northern Hemisphere than in the Southern Hemisphere. This review could benefit the algorithm development and improvement of air-sea turbulent heat flux products, provide insightful scientific guidance for selecting flux products for different applications, and characterize the advances in the global datasets of air-sea turbulent heat flux. • Fifteen global air-sea turbulent heat flux products from 1988 to 2020 are reviewed for accuracy and spatiotemporal patterns. • Most products show consistent global spatiotemporal patterns. • Differences among the products in regions are observed in the annual mean, interannual variability and annual trend. [ABSTRACT FROM AUTHOR]

Layered intrusions are fossilized natural laboratories that historically have constrained many fundamental principles of igneous petrology. Layered intrusions are typically stratiform, usually sill-like bodies of cumulate rocks, at least a few hundred metres to as much as 10 km thick, characterized by the presence of a variety of different types of layering over a range of length scales. They are the solid record of crystallization, differentiation and solidification processes of mainly basaltic magmas. The importance of layered intrusions also lies in hosting a significant proportion of the world's known reserves and resources of important critical metals: particularly, the majority of the global resource of platinum-group elements (PGE), chromium (Cr) and vanadium (V) and also very large resources of nickel (Ni), copper (Cu) and cobalt (Co). This paper summarizes the progress that has been made in the study of layered intrusions during the last three decades. The progress is marked by a number of novel observations from layered intrusions. Among them are: (1) draping of igneous layering over a few-km-high sloping step in the chamber floor; (2) development of igneous layering on the overturned to undercutting portions of a chamber floor; (3) magmatic karstification of the floor cumulates, (4) existence of three-dimensional framework of crystals in (oxide) cumulates; (5) systematic variations in dihedral angles between touching grains, and other microtextural features; (6) Cr-rich structures at the base of magnetitite layers; (7) co-existence of melt inclusions of contrasting composition in minerals; (8) thermal and chemical histories recorded by plagioclase; (9) textural and chemical features of minerals revealed by X-ray microscopy, (10) intrusion-scale to mineral-scale isotopic heterogeneity; (11) out-of-sequence zircon ages; and (12) skeletal/dendritic growth of minerals revealed by minor element zonation. The progress is also evident from development of several new concepts and refinement of some established ones. These include: (1) time and length scales in layered intrusion processes, (2) catastrophically fast growth of magma chambers, (3) out-of-sequence emplacement in layered intrusions, (4) large-scale slumping and mineral sorting in layered intrusions, (5) production of monomineralic cumulates from single phase-saturated melts, (6) origin of non-cotectic cumulate by in situ growth, (7) the arrival of new phases on the liquidus, (8) inward propagation of solidification fronts, (9) mushy and hard chamber floor, (10) absence of roof sequences due to their disruption, (11) basal reversals and chilled margins, (12) adcumulus growth theory, (13) compositionally stratified magma chambers, (14) melt-sediment interactions during magma chamber growth, (15) lateral reactive infiltration in a crystal mush, (16) reactions involving conjugate immiscible liquids in crystal mushes, and (17) constraints on subsolidus processes from non-traditional Fe-Mg-Cr stable isotopes. Finally, we show that the major controversies regarding layered intrusions currently revolve around whether: (a) the microstructure of igneous rocks are primary or secondary and (b) compaction in layered intrusions is pervasive or non-existent (c) large, long-lived and entirely-molten magma chambers exist or not. The review shows that layered intrusions provide ground-truth information on the processes of magma crystallization, differentiation, and solidification in crustal chambers as well as on mechanisms of ore-forming elements concentration into economically viable mineral deposits. We propose a few lines for future research that may potentially raise igneous petrology to a new level of understanding of the processes that govern the evolution of terrestrial magmatic systems. [ABSTRACT FROM AUTHOR]

The Proterozoic geological records in eastern South China preserve a history linked to the Columbia and Rodinia supercontinent cycles and provide key constraints in understanding the geodynamic evolution of East Asia. However, it is uncertain if SW Hainan, Yangtze and Cathaysia were located in the interior or periphery of the Precambrian supercontinents, how they were connected prior to the formation of a united South China, whether the early Neoproterozoic Proto-Huanan subduction was long- or short-lived, and how and when Yangtze and Cathaysia were assembled along the Jiangnan Orogen. This paper provides an overview of key geological observations for the eastern Yangtze and Cathaysia with respect to Proterozoic tectonics. Our synthesis shows that the SW Hainan in the Mesoproterozoic (ca. 1.45 Ga) developed in a non-orogenic rift setting in the interior of Columbia. SW Hainan, together with SW Yangtze, drifted to the margin of Rodinia by ∼1.05 Ga. Furthermore, SW Hainan might have been part of the Mesoproterozoic Albany Fraser Orogen at ca. 1.30–1.05 Ga. Cathaysia and eastern Yangtze display distinct geological signatures in the early Neoproterozoic and Cathaysia remain separated from Yangtze until at least ca. 1.0 Ga. The ca. 1.0–0.9 Ga felsic igneous rocks in Cathaysia to the east of the Jiangshan-Shaoxing suture zone are mostly characterized by negative ε Hf (t) values, and distinct from those in the coeval Shuangxiwu arc to the west of the Jiangshan-Shaoxing suture zone, which have positive ε Hf (t) values. Igneous rocks dated at ca. 870–830 Ma (mainly ca. 850–830 Ma) are extensive in the Huaiyu and Jiangnan Orogen but poorly developed in Cathaysia. Neoproterozoic sedimentary rocks of Cathaysia contain abundant ca. 980 Ma detrital grains but only minor ca. 860–830 Ma grains. In contrast, in the Jiangnan and Huaiyu, the sedimentary rocks contain a dominant ca. 860–830 Ma detrital zircon age-peak but ca. 980 Ma grains are scare. Rift-related bi-model igneous rocks, ranging in age from ca. 810 Ma to ca. 750 Ma, represented by the Banxi, Likou and Mamianshan groups and their equivalents, are extensively developed in Cathaysia and Huaiyu, and the Jiangnan Orogen. These rift-related successions are separated from the Cangshuipu and Luojiamen conglomerates across an angular unconformity, which are in turn unconformable on the Lengjiaxi and Xikou groups. It is herein proposed that an early Neoproterozoic (ca. 1.0–0.9 Ga) accretionary orogen developed within the Cathaysia and lay along strike from the synchronous Eastern Ghats Orogen of India. A long-lived Neoproterozoic (ca. 0.97–0.83 Ga) Proto-Huanan arc-trench system resulted in the development of the ca. 0.98–0.88 Ga Shuangxiwu intra-oceanic arc, ca. 0.87–0.83 Huaiyu continental arc and ca. 0.87–0.83 Jiangnan intra-continental back- arc basin in response to the ongoing westward-subduction beneath the eastern Yangtze. At ca. 0.87 Ga, the arc-trench system switched from an intra-oceanic to a continental Andean margin setting. Such a system might be compatible to the NW India South Delhi Orogen at the periphery of Rodinia. Our synthesis shows that the united proto-South China was finally created by the ca. 830–810 Ma assemblage of the Yangtze with Cathaysia along the Jiangnan Orogen and was followed by the post-orogenic rifting due to the breakup of Rodinia. [ABSTRACT FROM AUTHOR]

Reconstruction of proportions between juvenile and recycled crust remains challengeable because a big part of juvenile source magmatic rocks formed at intra-oceanic arcs, can be destroyed by surface and tectonic erosion leaving, at best, greywacke sandstones. Such sandstones are typically hosted by accretionary complexes, which study, therefore, is of crucial importance. In this paper we review available geological and micropaleontological data and present first U Pb detrital zircon ages, geochemical data and isotope (Sm Nd, Lu Hf) data from sandstones of the late Cambrian-early Ordovician Zasur'ya accretionary complex (AС) of NW Altai. No island-arc units have ever been reported there. The Zasur'ya AC includes ocean plate stratigraphy (OPS) magmatic and sedimentary rocks of three formations, Listvenny (l. Cambrian), Talitsa (Tremadocian) and Marcheta (Floian), which age was constrained by microfossils. The OPS assemblage includes basalt, pelagic chert and hemipelagic siliceous mudstone and siltstone, and sandstone. We analyzed zircons in five samples. The distributions of U Pb ages of detrital zircons from five samples of sandstones are all unimodal with main peaks at ca. 488 Ma (Listvenny Fm.), 491 Ma (Talitsa Fm.) and 485 Ma (Marcheta Fm.). The Precambrian ages are very few. The maximum deposition ages inferred from the youngest populations of zircon ages are ca. 464 Ma. Compositionally, the sandstones are greywackes or feldspar litharenites. The Listvenny and Talitsa sandstones are higher silicic (SiO 2av. = 68.5 wt%) compared to Marcheta samples (SiO 2av. = 60.5 wt%). The major and trace element features of all sandstones are similar to supra-subduction intermediate-felsic (Listvenny, Talitsa) and mafic-intermediate (Marcheta) magmatic rocks. All samples yielded positive values of zircon ɛHf(t) (+4.3 to +20.1) and bulk-rock ɛNd(t) (+0.6 to +4.8) indicating juvenile magmatic rocks in the provenance. However, the Listvenny and Talitsa samples show lower ɛNd(t) (1.3 and 0.8, respectively) than those of the Marcheta Fm. (4.7). Probably the Zasur'ya sandstones were deposited in a back-arc basin (Listvenny, Talitsa), and fore-arc basin (Marcheta). All Zasur'ya greywacke sandstones were derived by destruction of a single late Cambrian - Early Ordovician intra-oceanic arc. The Zasur'ya intra-oceanic arc was identified in NW Altai for the first time and it represents a new site of juvenile crustal growth in the CAOB. [ABSTRACT FROM AUTHOR]

Inorganic geochemistry is a powerful tool in paleolimnology. It has become one of the most commonly used techniques to analyze lake sediments, particularly due to the development and increasing availability of XRF core scanners during the last two decades. It allows for the reconstruction of the continuous processes that occur in lakes and their watersheds, and it is ideally suited to identify event deposits. How earth surface processes and limnological conditions are recorded in the inorganic geochemical composition of lake sediments is, however, relatively complex. Here, we review the main techniques used for the inorganic geochemical analysis of lake sediments and we offer guidance on sample preparation and instrument selection. We then summarize the best practices to process and interpret bulk inorganic geochemical data. In particular, we emphasize that log-ratio transformation is critical for the rigorous statistical analysis of geochemical datasets, whether they are obtained by XRF core scanning or more traditional techniques. In addition, we show that accurately interpreting inorganic geochemical data requires a sound understanding of the main components of the sediment (organic matter, biogenic silica, carbonates, lithogenic particles) and mineral assemblages. Finally, we provide a series of examples illustrating the potential and limits of inorganic geochemistry in paleolimnology. Although the examples presented in this paper focus on lake and fjord sediments, the principles presented here also apply to other sedimentary environments. • Inorganic geochemical proxies are not universally applicable. • Simple multivariate statistics allow associating elements with sediment components. • Variations in most elements reflect sediment grain size and provenance. • Log-ratios effectively reduce the limitations inherent to XRF core scanner analysis. [ABSTRACT FROM AUTHOR]

The timing, kinematics, and geodynamic evolution of the India-Asia continental collision are crucial to understanding the geological and geomorphological evolution of the Himalayan-Tibetan orogen. However, the debate over how and when the collision occurred persists due to disputes concerning the reliability of paleomagnetic data obtained on both sides of the suture zone. This paper presents a comprehensive analysis and evaluation of paleomagnetic studies to address this controversial issue. The study focuses on well-preserved Cretaceous-Paleocene rocks from the Lhasa and Tethyan Himalaya (TH) terranes over the past two decades. We conclude that: (1) the paleomagnetic data of the Linzizong Group of the Lhasa Terrane and the Zongpu Formation of the TH are in their primary origin and can be used for tectonic reconstruction; (2) the Tethys Himalaya Basin (THB) was generated due to the rifting of the TH from Greater India before the Late Cretaceous; (3) the southern margin of Asia was aligned in the NW-SE direction before the India-Asia collision. The study suggests a quasi-synchronous multi-stage collision where the TH collided with the Trans-Tethyan subduction system in Late Cretaceous-Early Paleocene times (∼65 Ma), followed by collision with Asia at 56–59 Ma. Finally, the India Craton collided with the TH, resulting in the synchronous closure of the THB at approximately 40 Ma. [ABSTRACT FROM AUTHOR]