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Background: Numerous studies showed an effect of weather on physical activity (PA) levels in children. However, no study has yet examined the relevance of personal factors in this relationship. Therefore, this study analyzes (1) whether there are systematic interindividual differences in the extent to which weather affects the PA behavior and (2) whether physical literacy (PL) moderates the weather–PA association in children. Methods: A total of 951 children in 12 Danish schools (age 9.76 [1.59] y; 54.3% girls) completed objective PA assessments via accelerometry (moderate to vigorous PA, light PA, and sedentary behavior). Local weather data (precipitation, wind speed, temperature, and sunshine duration) were provided by the Danish Meteorological Institute. Participants' PL was measured employing the Danish version of the Canadian Assessment of Physical Literacy-2. The 4116 accelerometer days underwent longitudinal multilevel analyses while considering their nesting into pupils and school classes (n = 51). Results: Fluctuations in all PA indicators were significantly explained by variations in weather conditions, especially precipitation (P ≤.035). Significant interindividual differences were found for 9 of 12 analytical dimensions, suggesting that weather changes influence PA behavior differently across individuals (especially moderate to vigorous PA, χ2[4] ≥ 11.5, P ≤.021). However, PL moderated the relationship between weather and PA in only 2 of the 48 analytical constellations. Conclusions: Despite the varying impact of weather on PA across individuals, the present study favors a main effect model in which weather and PL exert independent effects on children's PA. The insufficient support for PL as a moderating factor calls for future studies to test alternative mechanisms in the weather–PA association. [ABSTRACT FROM AUTHOR]

Clouds play a pivotal role in determining Earth's climate, impacting several atmospheric processes influencing the weather. The study explores the temporal variations in cloud base height (CBH) over Pune, a tropical station, from 2017 to 2023 using a Laser-Based Ceilometer with a range of 0–7500 m. Our analysis shows seasonal trends in CBH, with the monsoon season exhibiting unique characteristics showing the lowest average CBH and minimal diurnal changes during the study period. Conversely, the pre-monsoon, post-monsoon, and winter season show a gradual rise of CBH in the morning, maintaining higher levels until late afternoon, followed by a decline in the evening. Analysis of the diurnal frequency of cloud occurrence at 500 m intervals reveals the monsoon season's dominance in the 500 m to 1000 m layer. Throughout the year, low cloud bases (CBH <2000 m) are most frequent, outpacing the frequency of mid and high cloud bases. High cloud base (7500 < CBH > 6000 m) is the least common, showing a semi-diurnal pattern in winter with peaks around noon and midnight. These findings not only enhance our understanding of Pune's atmospheric behaviour but also offer valuable information for weather prediction, climate modelling, and environmental monitoring. [ABSTRACT FROM AUTHOR]

Lived experiences with urban heat are often rendered invisible, shrouded under the cloak of neoliberal resilience discourse and sanitised heat mapping and messaging. This is particularly tragic for disadvantaged at‐risk populations in white, settler colonial contexts where heat tolerance is worn as a badge of honour. Here, drawing upon semi‐structured interviews and focus group discussions in Perth, Western Australia, and with feminist emphasis on the embodied, the everyday, and bodily difference, we illustrate how corporeal thermal insecurities among rough sleepers, people with disabilities, and across intersectional disenfranchisement immobilise and dehumanise. By employing the logic of structures of violence to thermal suffering, we reveal how housing and energy precarity exacerbate entrenched racism and normalised discrimination. Our aim is to expand current debates on heat action plans (HAPs) and cool refuges by examining what “better weathering” could mean in practice, via the materialities of heated urban bodies (HUBs) and to demonstrate how such counter‐hegemonic heat mapping serves as a corporeal critique of the neoliberal resilient subject. [ABSTRACT FROM AUTHOR]

The aim of the research is to determine changes in the composition of selected gasoline compounds in cotton carpet samples due to different weathering times. EVO 95 gasoline was used as a fire accelerant and a cotton carpet was used as a matrix. The samples were exposed to various weathering durations (0–360 min) in laboratory conditions. We investigated samples that were unburnt (only weathered) and samples that were burned and subsequently subjected to further weathering. Residual gasoline compounds in carpet samples were determined by gas phase extraction (headspace – HS) coupled with gas chromatography (GC) and mass spectrometry (MS). We focused on the comparison of selected gasoline compounds; toluene, ethylbenzene, p-xylene, 1,2,3-trimethylbenzene (TMB), 1,3,5-trimethylbenzene and naphthalene. The biggest changes were determined in the reduction of the intensity of most volatile compounds (alkylalkanes), where toluene decreased by 11.92%. A similar but not so pronounced trend, occurred in the burned samples, where toluene decreased by 7.40%. Minor changes occurred in alkyl derivatives of benzene, where some of the total 15 gasoline markers also occur, e.g. (1,2,3-trimethylbenzene, 1,3,5-trimethylbenzene). On the contrary, naphthalene as a heavier compound showed an increase in intensity about 0.42%. For burnt samples, the increase was 1.31%. The results show that largest changes can be observed after four or five hours of weathering, which implies the need for rapid sampling and subsequent timely analysis. [ABSTRACT FROM AUTHOR]

Urbanization has resulted in the widespread development of built-up areas, often without considering the local geology and geomorphology. To improve risk assessments related to landslides, it is essential to determine the physical and chemical properties of sediments. The aim of this study is to exemplify an already mobilized and reworked layer based on granulometric properties of the sediments and characterize the chemical and physical properties which have changed during or after the mass movement. Ten red clay layers were sampled near Kulcs (Hungary) from a sliding surface and its environment. We measured grain size distribution, major element and modal composition, furthermore, conduct particle shape analysis, respectively. Grain size distribution suggest that samples from the sliding surface are weathered, with the exhibiting reworking characteristics. We calculate the weathering index from the major elements, which, in combination with the particle shape analyses of the silt fractions, indicate that the morphological parameters of the samples are in relation with weathering index. According to our results, while a fresh sliding event leaves marks on the granulometric properties, the main process which affects the grain morphology is the chemical abrasion (post the mass movement) and not the landslide event. [ABSTRACT FROM AUTHOR]

Preventing the oxidation of oxide‐C refractories used as working linings in steelmaking vessels is crucial for maintaining their performance and extending their lifetime. This study introduces a novel methodology for evaluating and quantifying the protective effect that adhered slag can have on the oxidation of the refractory lining of steelmaking ladles. The article details the ad‐hoc methodology itself, including the technique for adhering the slag to the refractory sample and the specifically developed equipment used. The proposed experimental approach includes the evaluation of how the environmental degradation of the slag layer affects the protection it provides to the refractory against attack by environmental oxygen. Finally, the methodology's ability to provide reliable and reproducible results is shown by its application on MgO–C refractories, the most widely used type of oxide‐C products in the steelmaking industry. [ABSTRACT FROM AUTHOR]

Background: The weathering intensity and geochemical properties of a rock contribute to shallow landslide occurrences. This study aims to establish the role of rock weathering in shallow slope instability in low-grade metamorphic rocks of the Lesser Himalaya region of central Nepal. The rocks of the Kuncha Formation, which consist of phyllites, metasandstones, and gritty phyllites are characterized by the formation of shallow landslides. Field characterization of the rock mass within the landslide body, along with petrographic observations, clay mineral analysis, and major bulk geochemistry were adopted to establish a relationship between rock weathering and landslide occurrence. Results: The landslides distributed within the Kuncha Formation in the study area are debris-related slides and falls, rock falls, and complex slides. Microscopic petrographic observation of rock from the landslide area revealed well-developed microcracks and intergranular microfractures within the weathered samples, which suggests extensive disintegration and physical alteration. Kinematic analysis of the landslide slope revealed that discontinuities and bedding planes also affected the failure of the slope. The occurrence of neo-formed clay minerals and the conversion of biotite-muscovite to vermiculite, kaolinite, and mixed-layer clays indicate chemical weathering. The CIA ranges between 71 and 80 for the rock samples and between 72 and 84 for the soil samples, signifying moderate to extreme weathering effects. The higher values of PIA and CIW reveal K-feldspar and plagioclase alteration to clay minerals by weathering and alteration. CIA-LOI plots reveal significant relationships corresponding to weathering effects. Conclusion: The transition of rock from a fresh to a moderately weathered state and the development of clay minerals and major discontinuities played a crucial role in shallow landslide occurrence. The weakened physical properties of the rock mass due to weathering coupled with unfavorable joints and fracture conditions have led to instability of the hillslopes in the study area. It was observed that one of the driving factors that drives slopes to erosion and landslides is weathering. The dominant occurrence of landslides in the weathered rock domain within the study area validates the occurrence of landslides and weathering interconnections. [ABSTRACT FROM AUTHOR]

Forecast verification is critical for continuous improvement in meteorological organizations. The Jive verification system was originally developed to assess the accuracy of public weather forecasts issued by the Australian Bureau of Meteorology. It started as a research project in 2015 and gradually evolved to be a Bureau operational verification system in 2022. The system includes daily verification dashboards for forecasters to visualize recent forecast performance and "Evidence Targeted Automation" dashboards for exploring the performance of competing forecast systems. Additionally, Jive includes a Jupyter Notebook server with the Jive Python library, which supports research experiments, case studies, and the development of new verification metrics and tools. This paper describes the Jive verification system and how it helped bring verification to the forefront at the Bureau of Meteorology, leading to more accurate, streamlined forecasts. Jive has provided evidence to support forecast automation decisions and has helped to understand the evolving role of meteorologists in the forecast process. It has given operational meteorologists tools for evaluating forecast processes, including identifying when and how manual interventions lead to superior predictions. Work on Jive led to new verification science, including novel metrics that are decision-focused, including diagnostics for extreme conditions. Jive also provided the Bureau with an enterprise-wide data analysis environment and has prompted a clarification of forecast definitions. These collective impacts have resulted in more accurate forecasts, ultimately benefiting society and building trust with forecast users. These positive outcomes highlight the importance of meteorological organizations investing in verification science and technology. SIGNIFICANCE STATEMENT: We describe how the Jive verification system helped transform weather forecasting operations at the Bureau of Meteorology. The project highlighted the role humans play in the weather forecast process and aided in streamlining the forecast production process while improving accuracy. New tools, data, dashboards, and novel verification science have allowed operational meteorologists to deeply embed verification activities into their daily forecast process. These activities have allowed operational meteorologists to create evidence-based strategies for modifying automated gridded forecasts before issuing forecasts to the public. Jive has also been used as a tool to run and evaluate retrospective experiments to support forecast system development. [ABSTRACT FROM AUTHOR]

The effects of rare earth elements (REEs) on the corrosion behavior of weathering steels under a simulated immersion environment and a real atmospheric environment have been investigated in this paper. Although the corrosion rate of the indoor accelerated corrosion experiment (0.01 mol/L NaHSO3) is much higher than that of the real atmospheric exposure experiment, the addition of REEs can highly improve the corrosion resistance of test steels under both conditions. The improvement of the corrosion resistance can be attributed to the quick transformation of γ‐FeOOH into α‐FeOOH and the accelerated formation of a stable rust layer by REEs. Furthermore, the segregation of the REE inner rust layer increases the density of the rust layer and prevents corrosive particles from eroding the matrix. REEs can also promote the segregation of Cu, Cr, and other alloying elements in the rust layer, thus blocking the cracks and holes and enabling the formation of a continuous rust layer with good adhesion. [ABSTRACT FROM AUTHOR]

The present study provides multidisciplinary research on the alteration of petrographic, mineralogical, geochemical characteristics, and physical properties of Himachal gneiss due to weathering. Three different weathering grades fresh, slightly, and moderately weathered gneiss are collected from Kullu, Himachal Pradesh, India. The petrographic and mineralogical analyses are done by thin section and XRD analyses. The microstructural and geochemical studies of gneiss samples were performed using scanning electron microscopy (SEM) and X-ray fluorescence (XRF) respectively. The petrographic images revealed a large amount of alteration in the plagioclase due to weathering. The pervasive sericitization of plagioclase is observed in moderately weathered gneiss samples. The quartz grains are intact and only minor fracturing in some quartz grains is observed in moderately weathered gneiss samples. The SEM images indicate that the inter-granular and intra-granular micro-cracks increase with the weathering grades. The XRF results are used to obtain the different chemical weathering indices and their suitability for Himachal gneiss. Among twenty-five chemical weathering indices, the CIA, CIW, alkaline ratio, PIA, LOI, and WI show a suitable trend and can be used for assessing the weathering of Himachal gneiss. In addition, alterations in the physical properties of gneiss are observed due to weathering. The bulk, dry, saturated densities and slake durability index decrease while the porosity increases with the progressive weathering of gneiss. The progressive weathering significantly reduces the gneiss's uniaxial compressive strength (UCS). For all three weathering grades of gneiss, the maximum and minimum values of UCS were observed at 90˚ and 30˚ foliations, respectively. [ABSTRACT FROM AUTHOR]

The application of wood-plastic composites (WPCs) in outdoor settings has led to growing emphasis on their aesthetics and weathering. Therefore, it is necessary to study the effect of inorganic pigments on the weathering behavior of WPCs. In order to reveal the effect of inorganic pigments on the aging process of composites, wheat straw fiber/polyvinyl chloride composites (WSFPs) incorporating inorganic pigments were prepared, and accelerated weathering tests of the different colored WSFPs were carried out, and the changes of chemical structure, color stability, three-dimensional morphology, mechanical properties and physical properties of composites during weathering were investigated. The results showed that WSFPs with inorganic pigment showed high color stability and weather resistance during accelerated weathering. After weathering for 480 h, the color change exhibited by WY was the least, only 13.00, and its tensile, flexural and impact properties decreased by 5.14%, 8.72% and 3.10%, respectively. This study demonstrates that inorganic pigments not only enhance the aesthetics of WSFPs through coloration, but also effectively improve their weather resistance. Inorganic pigments help maintain the vibrant color and structural integrity of the material during long-term use. [ABSTRACT FROM AUTHOR]

Constraining the processes that fractionate barium isotopes is essential for utilising barium isotope ratios as environmental tracers. Barium concentration measurements from soils, rivers, and estuaries demonstrate that adsorption–desorption reactions significantly influence the distribution of fluid–mobile barium at the Earth's surface, potentially driving isotopic fractionation. To quantify the direction and magnitude of isotopic fractionation resulting from these reactions, a riverine and an estuarine series of batch experiments were conducted using environmentally important adsorbent minerals and surface waters. Himalayan river sediment and water samples were used to validate the experimental results. Adsorption–desorption reactions were found to be rapid, relative to the average transit time of sediment and water in catchments, and largely reversible. The direction and magnitude of isotopic fractionation in the riverine experiment series were consistent with the riverine field samples (preferential adsorption of the lighter isotopes). The reaction rate, reversibility, and magnitude of isotopic fractionation were found to depend primarily on the mineral. Experiments performed with iron oxyhydroxides (goethite and ferrihydrite) resulted in a greater degree of fractionation compared to clay minerals (kaolinite and montmorillonite). Estuarine experiments, designed to simulate sediment passage through a salinity gradient, demonstrated a high degree of reversibility, with 77% to 94% of adsorbed barium desorbed upon the addition of seawater to freshwater-equilibrated clay minerals. The results of the estuarine experiments suggest that barium isotope ratios measured in marine paleo-archives (e.g. , corals) will reflect both the adsorbed and dissolved freshwater barium inputs to the ocean. The combined findings of this study indicate that the chemical and isotopic behaviour of barium differs from more conventional group 1 and 2 metal isotope systems due to a significant proportion of barium released from bedrock dissolution partitioning to mineral surfaces, rapid reaction rates between fluid–mobile phases, and a high degree of reaction reversibility. Consequently, riverine barium isotope ratios are likely to provide unique insights into the complex array of terrestrial weathering and erosion processes that sustain life on Earth. [ABSTRACT FROM AUTHOR]

Paleoenvironmental archives in East Antarctica have revealed significant changes during the Holocene, marked by ice sheet retreat leading to the isolation of submarine basins. These basins offer valuable insights into past climate, glaciology, and oceanography shifts that impact sedimentary processes. In this study, environmental magnetism and biogeochemical proxies to investigate the Mid-to-Late-Holocene transitions in Pup Lagoon, a coastal isolation basin is presented. Our findings reveal distinct stratigraphic zones reflecting shifts from marine to lacustrine environments. The results reveal predominant mechanical weathering in the Stornes region, producing coarse-grained "soft" ferrimagnetic minerals. Notably, a period of warm oceanographic conditions between 6000 and 4722 cal. yr BP was characterized by mixed magnetic grain sizes and ultrafine superparamagnetic grains, indicating relatively oxic open waters in the basin. Subsequent shifts to reducing conditions coincide with persistent marine sea ice cover from 4722 to 2634 cal. yr BP, favoring the retention of coarse-grained ferrimagnets. Finer magnetic grain sizes between 2634 and 2185 cal. yr BP was attributed to the increased freshwater inputs associated with the Mid-Holocene Hypsithermal. Further, diagenetic changes under persistent sea ice cover between 2185 and 1970 cal. yr BP led to the selective dissolution of fine-grained ferrimagnets. Transitioning to freshwater isolated basin conditions between 1970 and 588 cal. yr BP, fine ferrimagnet precipitation indicate oxic to suboxic conditions alongside drier conditions. Biogenic productivity increased post-isolation, which was reflected in increased (Total Organic Carbon) TOC and (Total Nitrogen) TN percentages. Additionally, the presence of greigite in the isolated phase sediment indicates reducing conditions owing to organic matter decomposition. Notably, χfd% exhibits an inverse trend to sea ice concentration, potentially indicating anoxic-dysoxic conditions due to the presence of sea ice. These observations align with broader regional sea ice concentration changes, emphasizing the interconnected behavior of local and regional factors shaping Antarctic coastal environments. [ABSTRACT FROM AUTHOR]

Sense of place and identity are related to the weather, and to memories and perceptions of what constitutes "normal" weather for a particular place. Weather is an important ingredient of cultural life; thus, long‐term changes to weather patterns can affect sense of place and sense of reality, although these changes will not be experienced uniformly. We argue that weather and climate should thus be considered forms of intangible cultural heritage, which we refer to as weather‐heritage. Drawing attention to place‐specific weather‐heritage that is threatened by climate change may increase support for mitigation and adaptation policies and encourage behavior change from individuals and governments. A heritage/memory lens can also draw attention to the ways in which lost weather‐heritage should be memorialized, ensuring that the right to memory of lost weather‐heritage is maintained. We therefore argue for a new research focus on weather‐heritage and memory, to understand how people remember and ascribe significance to particular weather types and patterns, and to document weather‐heritage that has been lost or is likely to be lost as climate changes. One purpose of this research should be to ensure that weather‐heritage is plural and does not become a majoritarian and exclusionary exercise in uncritical nostalgia. This article is categorized under:Climate, History, Society, Culture > Ideas and KnowledgePerceptions, Behavior, and Communication of Climate Change > Perceptions of Climate ChangeTrans‐disciplinary Perspectives > Humanities and the Creative Arts [ABSTRACT FROM AUTHOR]

This study explores the blending of poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) with rice straw micro-particles (10 to 30 wt%, ≤ 250 μm) to create biocomposites using a kinetic mixer. It examines the effects of chain extender (J) and maleic anhydride (MA) as compatibilizers on material properties. Biocomposites underwent 500 h accelerated weathering to simulate environmental conditions, with analysis via Fourier-transform infrared spectroscopy (FTIR), mechanical testing, dynamic mechanical analyses (DMA), and rheological evaluations. Results indicate that the chain extender's superior performance over MA, generating 6% insoluble content compared to 1% with MA. Scanning electron microscopy (SEM) revealed reduced interfacial voids in biocomposites treated with compatibilizers. The addition of the rice straw was found to increase the tensile modulus from 2.3 to 3.4 indicating a 43% increase after 40 wt% rice particles; all the while reducing the tensile strength and ductility. Post-weathering, Joncryl® treated samples retained properties better than MA-treated ones, showing enhanced crosslinking and less decline in tensile strength (10–19% reduction for J vs. 27–30% for MA). Compatibilizers, especially the chain extender, play a crucial role in strengthening PLA and PBAT biocomposites, particularly under accelerated weathering. [ABSTRACT FROM AUTHOR]

The interaction between particles and proteins is a key factor determining the toxicity responses of particles. Therefore, this study aimed to examine the interaction between the emerging pollutant polyethylene terephthalate micro/nanoplastics from water bottles with bovine serum albumin. The physicochemical characteristics of micro/nanoplastics were investigated using nuclear magnetic resonance, x‐ray diffraction, Fourier transform infrared, dynamic light scattering, and x‐ray energy dispersive spectroscopy after exposure to various concentrations and durations of protein. Furthermore, the impact of protein‐treated micro/nanoplastics on biological activities was examined using the mitochondrial activity and membrane integrity of A549 cells and the activity and biofilm production of Staphylococcus aureus. The structural characteristics of micro/nanoplastics revealed an interaction with protein. For instance, the assignment of protein‐related new proton signals (e.g., CH2, methylene protons of CH2O), changes in available protons s (e.g., CH and CH3), crystallinity, functional groups, elemental ratios, zeta potentials (−11.3 ± 1.3 to −12.4 ± 1.7 to 25.5 ± 2.3 mV), and particle size (395 ± 76 to 496 ± 60 to 866 ± 82 nm) of micro/nanoplastics were significantly observed after protein treatment. In addition, the loading (0.012–0.027 mM) and releasing (0.008–0.013 mM) of protein also showed similar responses with structural characteristics. Moreover, the cell‐based responses were changed regarding the structural and surface characteristics of micro/nanoplastics and the loading efficiencies of protein. For example, insignificant mitochondrial activity (2%–10%) and significant membrane integrity (12%–28%) of A549 cells increased compared with control, and reductions in bacterial activity (5%–40%) in many cases and biofilm production specifically at low dose of all treatment stages (13%–46% reduction) were observed. [ABSTRACT FROM AUTHOR]

Studying taphonomy is crucial for understanding how post-depositional processes impact archaeological remains. This knowledge is pivotal for accurately interpreting the archaeological record. Although taphonomy has a long tradition in archaeology, it is less developed in the analysis of stone tool residues compared to other subdisciplines. To address this gap, our study aims to further develop our understanding of the preservation potential of stone tool residues in temperate environments through actualist experiments. To achieve this, we develop a multidimensional experimental program that features the first biweekly monitoring of weathering processes on residues over a one-year cycle, aiming to understand the short-term effects of weathering immediately after tool discard. Additionally, the program involves the study of longer-term burial and weathering visual effects on different residue types within various previously unexplored depositional environments. This approach allows us to observe the visual effects of both weathering and burial processes and to improve our understanding of the different mechanisms involved in the diagenesis of stone tool residues. While known factors such as microbial activity and soil acidity play a primary role in residue decay, specific stone tool-related factors also prove important, underscoring the need to develop further a specific branch of taphonomy related to stone tool residues. Moreover, our results show that certain residue types may survive within these environments that are often considered as being hostile. A residue analysis of stone tools from temperate contexts may thus contribute unique data that can improve our understanding of past human behaviour. Future research with more diverse residue types and depositional conditions will permit further refinement of our understanding of how taphonomy affects residue preservation and enhance the reliability of residue identifications. As such, stone tool residue analysis will become firmly rooted within broader functional approaches to address how humans use stone tools and how this affects stone tool variability. [ABSTRACT FROM AUTHOR]

Studying the effects of weathering on the mechanical properties and microscopic evolution of weathered granite soil (WGS) is essential for connecting microstructure with macroscopic behavior. This study conducts systematic monotonic and cyclic triaxial tests, along with a series of microscopic tests on WGS samples, to explore the influence of weathering on WGS mechanical properties and the mechanism of granite weathering. Results indicate that both effective internal friction angle and effective cohesion decrease progressively with increased weathering. Completely weathered granite (CWG) exhibits greater dynamic strength compared to granite residual soil (GRS). Additionally, as weathering progresses, quartz fragments are lost, while feldspar and biotite weather to form secondary minerals such as kaolinite and illite, leading to an overall enrichment in aluminum and iron in the granite. Weathering causes structural deterioration of WGS. Finally, the mechanical parameters of WGS and their chemical weathering indices show a coefficient of determination ranging from 60 to 99%. This study helps elucidate the fundamental causes of performance changes in WGS, thereby optimizing engineering design and enhancing disaster prediction accuracy, while providing new research perspectives and experimental evidence for WGS. [ABSTRACT FROM AUTHOR]

The mixed Fe(II)/Fe(III) mineral magnetite [Fe3O4] of various stoichiometric and non‐stoichiometric compositions have been reported in Martian soils and rocks by several rover missions. Magnetite is an important paleomagnetic indicator mineral and can serve as a 'biogeobattery' as a consequence of its magnetic properties and the mixed valence state of iron in its structure. Here, we assess the extent of oxidative weathering of magnetite in presence of chlorate and bromate containing solutions that are likely important oxidants on Mars. Oxyhalogen species, chlorate and bromate, produced non‐stoichiometric magnetite [Fe(II)/Fe(III) < 0.5] in Mars‐relevant, near‐neutral pH fluids; no other ferric minerals were produced. The same results were observed in highly acidic fluids with or without oxyhalogens. Owing to its resistance to extensive oxidation, magnetite can serve as an important archive of geochemical, paleomagnetic, and astrobiological information in samples that will be returned by the Mars Sample Return mission. Plain Language Summary: Magnetite is an iron oxide that contains both Fe(II) and Fe(III) in its crystal structure. The Fe(II) to Fe(III) ratio in an ideal (i.e., stoichiometric) magnetite is 0.5, that decreases as Fe(II) in its structure oxidizes to Fe(III) thereby forming non‐ideal (i.e., non‐stoichiometric) magnetite. Owing to its unique structure, magnetite can serve as an important paleomagnetic indicator mineral and a source of energy for microorganisms. Therefore, understanding the survivability of magnetite in presence of the harsh oxidizing chemical environment on Mars is important. Here, we conduct laboratory experiments in Mars‐like fluids to test the reactivity of magnetite in presence of strong and effective oxidants that have previously been shown to be active on Mars. Our results show that magnetite is resistant to extensive oxidation in presence of chlorate and bromate solutions to an extent that is much greater than other Fe(II) minerals like iron sulfides, and forms non‐stoichiometric magnetite making it a useful target for analyses of samples from the Mars Sample Return mission aimed at understanding Mars' magnetic history and habitability. Key Points: Magnetite shows resistance to oxidation by oxyhalogen compounds (chlorate and bromate) in Mars‐relevant fluidsNon‐stoichiometric magnetite on Mars may be formed by aqueous alteration of stoichiometric magnetite by oxyhalogen compoundsMagnetite likely preserves geochemical, paleomagnetic and astrobiological information and is an important target mineral in Mars return samples [ABSTRACT FROM AUTHOR]

A linear relationship between rates of physical erosion and chemical weathering is apparent in slowly eroding landscapes. Whether the relationship remains linear in rapidly eroding landscapes is less clear. Field‐based research into this relationship between erosion and weathering rates has largely been conducted in temperate climates with granitic bedrock. In tropical settings, the contribution of chemical mass loss to total denudation may approach, or even exceed, that of erosion. We report 10Be‐in‐quartz cosmogenic radionuclide and soil chemistry data from the Suckling‐Dayman Metamorphic Core Complex (SDMCC) in Papua New Guinea. Despite being exhumed at cm‐per‐year rates, its lower‐plate domed and striated morphology suggests minimal denudation, which is confirmed by our 10Be‐in‐quartz data (0.02–0.18 mm/yr). We suggest that rolling hinge‐style back‐rotation of the SDMCC's lower plate and the combination of a tropical climate and highly weatherable metabasalt bedrock have played a fundamental role in preserving the tectonic topography of this remarkable metamorphic core complex. Plain Language Summary: Where mountains are raised (uplifted) slowly by plate tectonics, erosion (the removal of rocks/soils) tends to be slow. Where erosion is slow, chemical weathering (the local breaking down or dissolving of rocks/minerals) is usually slow as well. This observation has been made in mountainous regions around the world with temperate climates, and where mountains consist predominantly of granitic rocks. However, much less is known about how rates of erosion and weathering relate in tropical climates where mountains rise rapidly. We studied a unique geological structure in tropical Papua New Guinea (the Suckling‐Dayman Metamorphic Core Complex, SDMCC) to provide new data for addressing this knowledge gap. We measured denudation rates (the sum of physical and chemical mass loss) using a method that is based on the accumulation of atomic particles that form in the crystal lattice of minerals in rocks and soils by cosmic rays. Our denudation rates are much slower than the rate at which the SDMCC is being raised by tectonic processes, requiring some erosion‐limiting mechanism(s). The chemical compositions of basaltic soils from the SDMCC, however, imply intense weathering. We argue that the style of tectonic uplift and the tropical weathering regime are responsible for the slow denudation rates. Key Points: 10Be‐in‐quartz denudation rates of the rapidly uplifting Suckling‐Dayman Metamorphic Core Complex are in the range of 0.02–0.18 mm/yrRapid, intense weathering of its metabasaltic footwall bedrock is implied by mobile and immobile weathering indices in soil samplesThe pristine topography of Mount Dayman is strongly influenced by rolling hinge‐style tectonics and the tropical weathering regime [ABSTRACT FROM AUTHOR]

Developing high-performance mid and far infrared antireflection films is a significant requirement in the field of infrared optics. This study successfully prepared AR films composed of ZnS nanospheres for mid and far infrared bands using a combination of hydrothermal and sol-gel methods. Initially, ZnS nanospheres with uniform size and good monodispersity were synthesized via the hydrothermal method and subsequently coated on CdSe substrate through dip coating. The refractive index of the ZnS film is adjusted between 1.36 and 1.52. A significant AR effect was observed in ZnS nanospheres film on CdSe substrate at 3–5 μm and 8–14 μm, and the reflectance is approximately 3 % which is about 25 % lower than that of the uncoated sample. Upon coating with a TiO 2 protective layer, the reflectivity further decreased to about 0.6 % and the film demonstrated excellent weather resistance and mechanical properties. This work provides a novel approach for the preparation and regulation of mid and far infrared AR film, significantly contributing to the development of optical film. [ABSTRACT FROM AUTHOR]

This work permitted the understanding of processes in continental environments through the conditions of formation and deposition of alluvial clay materials in the Mbam Riverbanks (Central Africa). The Mbam River is the main tributary of the Sanaga River, one of the largest rivers in Central Africa. Twelve clay samples were collected from six wells, exhibiting different facies, and characterized using the Robinson-Köln pipetting, infrared spectroscopy, X-ray diffraction, and X-ray fluorescence. All the materials were classified as sandy clays. Their mineralogical assemblage is made of quartz, kaolinite, orthoclase, hematite/goethite, rutile, anorthite, and augite. The values for chemical, plagioclase, and mafic indices of alteration combined with those for Ba, Sr, and Rb/Sr ratio show that primary minerals like orthoclase, anorthite, and augite in source rocks are moderately altered. The studied materials are arkoses, wackes, shales, and Fe-Shales. Based on the index of compositional variability and on the SiO2/Al2O3 ratio, the associated sediments are considered immature. They are, according to Cr, Ni, and SiO2 contents, Al2O3/TiO2, Th/Sc, Th/Cr, and Cr/Ni ratios, and some binary provenance diagrams, from mafic, intermediate, and felsic sources. Values of the authigenic uranium, U/Th, V/Cr, and Ni/Co ratios permit to infer that they were deposited in an oxic environment. [ABSTRACT FROM AUTHOR]

Weather radar is a crucial tool for rainfall observation and forecasting, providing high-resolution estimates in both space and time. Despite this, radar rainfall estimates are subject to many error sources – including attenuation, ground clutter, beam blockage and drop-size distribution – with the true rainfall field unknown. A flexible stochastic model for simulating errors relating to the radar rainfall estimation process is implemented, inverting standard weather radar processing methods and imposing path-integrated attenuation effects, a stochastic drop-size-distribution field, and sampling and random errors. This can provide realistic weather radar images, of which we know the true rainfall field and the corrected "best-guess" rainfall field which would be obtained if they were observed in a real-world case. The structure of these errors is then investigated, with a focus on the frequency and behaviour of "rainfall shadows". Half of the simulated weather radar images have at least 3 % of their significant rainfall rates shadowed, and 25 % have at least 45 km2 containing rainfall shadows, resulting in underestimation of the potential impacts of flooding. A model framework for investigating the behaviour of errors relating to the radar rainfall estimation process is demonstrated, with the flexible and efficient tool performing well in generating realistic weather radar images visually for a large range of event types. [ABSTRACT FROM AUTHOR]

The research deals with the study of geomorphological phenomena of the drainage basin area of Wadi al-Qelt located between latitudes E°31 '55 "59 and °31 '48 "27 north, and longitudes N °35 '12 "22 and °35 '32 "51 east, and is one of the valleys of the eastern slopes of: the mountains of Ram Allah and Jerusalem, located within the mountain range of central Palestine, and ends in the Jordan Valley in the east of Jericho at the Jordan River coupler, It aims to vary the influence of geomorphological factors in the formation of terrain features, as the geological structure, both rock and tectonic, had the largest role in the geomorphological formation of the region, where doloms and soluble limestone rocks are spread, which resulted in the presence of karst forms, and marlin rocks that can be carved and eroded, which resulted in the active decline of slopes and the intensification of the number of river ranks. The second part of the structure, represented by the tectonic factor, resulted in its impact on the Afro-Asian groove (collapse pit), the direction and intensity of the general slope and the resulting increase in the energy of the valleys on vertical sculpture, deepening and formation of gorges and others, while the second factor represented by the ancient and current climate has clearly appeared its effects in the parts of the drainage basin, where the effects of the current climate appeared by the extreme variation of rain amounts between the parts of the study area, and the impact of the ancient climate was manifested in the lower basin Which was greatly affected by the change in the levels of the ancestor of the Dead Sea, which were alternating those parts, the study followed the descriptive, historical, and analytical approach to describe the geographical reality and its characteristics, trace geological eras, and employ (GIS) technology. It concluded that the basin consists of a set of structural geomorphological phenomena, phenomena resulting from erosion and sedimentation, and phenomena associated with weathering processes, and the study recommended carrying out many geomorphological studies on the region and identifying what abounds in the geography of the Wadi basin Clumping is a morphodynamic, morphodynamic process. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the effect of combined end-and-side grouting on the bearing properties of large-diameter rock-socketed bored piles in highly weathered rock layers. Eight full-scale pile load tests were conducted in the highly weathered rock layer to analyze the enhanced mechanism of the combined grouted bored piles. The test data from pile mechanical testing were compared with the recommended values in the current specification and geological survey report. The results demonstrate significant improvement in the side and end resistances of the combined grouted bored piles, resulting in a substantial increase in the bearing capacity and effective settlement control. It was observed that the construction of impact holes for bored piles can cause severe damage to highly weathered rock structures and weaken the mobilization of side and end resistances. Moreover, it was found that the calculation of the enhancement coefficient in the current specification underestimates the practical bearing capacity. The measured enhancement coefficients for the side and end resistance of piles in fully or highly weathered rock layers range from 2.49 to 3.05 and 2.24 to 2.43, respectively, which are more reasonable and feasible for the calculation. The research findings deepen the understanding of the bearing characteristics of large-diameter rock-socketed bored piles with combined grouting and provide valuable case references for the optimal design of large-diameter combined grouted piles for building foundations in Shenzhen, China. Highlights: Post-grouting had the potential to improve super high-building foundation reliability while reducing pile length and cost. The improvement effect and improvement mechanism of combined grouted bored piles embedded in highly rock strata were revealed. The influence of the size effect for large-diameter piles in highly weathered rock was revealed. The construction of impact holes for bored piles can cause severe damage to highly weathered rock structures and weaken the mobilization of side and end resistances. The enhancement coefficients for the side and end resistance of piles in fully or highly weathered rock layers were proposed. [ABSTRACT FROM AUTHOR]

Illitization of smectite in sedimentary systems, a process akin to "reverse weathering," is a diagenetic process that has significant implications for sediment paragenesis and hydrocarbon exploration. However, the potential influence of chemical weathering on the illitization of smectite and its possible control of the neogenesis of titanium (Ti)-oxides remain unclear. Altered volcanic tephra layers (i.e., K-bentonites) characterized by an interstratified illite-smectite (I-S) clay mineralogy serve as an excellent medium to investigate the illitization of smectite. In this study, we first investigated the fine structure of clay minerals and in situ nano-mineralogy of Ti-bearing minerals from altered volcanic ashes and then undertook a meta-analysis of geochemical compositional data for bentonites spanning a wide range of ages and depositional environments globally. We found that Ti mainly occurs as discrete micrometer-scale magmatic srilankite and nanoscale authigenic anatase crystals. During the weathering process, the magmatic srilankite partly dissolved under acidic conditions, resulting in a local buildup of Ti in porewaters. The I-S displays a platy habit and curved edges and is found closely associated with anatase crystals under TEM. Our compilation results combined with microscopic evidence suggest that chemical weathering may potentially promote the illitization reaction by changing the chemical composition of the fluids through increased terrestrial inputs and by creating larger pore spaces through the decomposition of weatherable components. Positive correlations between K and Ti are especially common in (K-)bentonites that are dominated by I-S, suggesting that I-S can adsorb Ti during the weathering process and provide a suitable site for the nucleation of anatase. Our study highlights the role of chemical weathering in the illitization of smectite and their combined effect on the formation of Ti-oxides. [ABSTRACT FROM AUTHOR]

It is necessary to analyze the characteristics of the water environment and factors influencing the basin in order to determine its current ecological status. This study aims to investigate the chemical properties in the Shichuan River Basin using Gibbs diagram, Piper triangle diagram, correlation analysis, factor analysis, and main ion ratio method. The enhanced Nemerow comprehensive index method and fuzzy comprehensive evaluation method are employed for river water quality assessment. The findings reveal that runoff water has a weak alkaline nature with low salinity. The hydrochemical type of river water includes Ca2++Mg2++Na+-SO42-, Ca2++Mg2+-SO42-+Cl-+HCO3-, Ca2++Na+-SO42-+Cl-+HCO3-. Silicite and dolomite weathering are identified as primary influencing factors, while evaporite weathering also contributes to variations in chemical composition within the basin's waters. Ca2+, Mg2+, SO42- and HCO3- originate from carbonate rock and silicate rock weathering processes, whereas Na+, K+ and Cl-, are primarily derived from evaporite weathering influenced by domestic sewage and agricultural activities. Agricultural production practices along with discharge of domestic sewage have an impact on Na+, K+, Cl- and NO3-concentrations in aquatic systems. Water quality at all three monitoring sections falls under level IV classification. Phosphorus emerges as a key limiting factor for eutrophication within this basin's watersheds. [ABSTRACT FROM AUTHOR]

The analysis of some geological features and structures can be used to determine Quaternary developments. Analyzing the types of landslides, their density, and scale is the key to identify the evolution of landforms. Based on this, the current research was carried out with the aim of spatial analysis of landslides that occurred in different lithologies of Mo'alem-Kelayeh basin, a part of eastern Alamut basinin of Qazvin province, between the longitudes 50°26'00" to 50°31'20" and the latitude 36°22'00" to 36°30'00", based on topographical, geological conditions, vegetation, the condition of waterways, and the proximity of different rocks in the area. According to the results, the Karaj, Rute, Shamshek and Neogene and destructive sediments are the most erodible formations in the studied area, which are the most important factors involved in the occurrence of mass movements on a micro and macro scale under the Mo'alem- Kelayeh basin. The nonresistant lithology is more extensive in the geographical levels downstream of the rivers. In such areas, in addition to the loosening of the lithology in wide sections, the material and energy flowing in the river also increases, if due to the lower slope of the slopes, the effect of the river on the movements of the slopes becomes more limited. In the terrestrial levels close to the ridge line, matter and energy are less and lithology is more resistant; But due to the greater slope of the slopes and the involvement of physical weathering in the porosity of the rocks, the effect of the river on the occurrence of surface slope movements increases. [ABSTRACT FROM AUTHOR]

Venus' surface and interior dynamics remain largely unconstrained, due in great part to the major obstacles to exploration imposed by its 470°C, 90 bar surface conditions and its thick, opaque atmosphere. Flyby and orbiter‐based thermal emission data provide opportunities to characterize the surface composition of Venus. However, robust interpretations of such data depend on understanding interactions between the planet's surface basaltic rocks and its caustic carbon dioxide (CO2)‐dominant atmosphere, containing trace amounts of sulfur dioxide (SO2). Several studies, using remote sensing, thermodynamic modeling, and laboratory experiments, have placed constraints on basaltic alteration mineralogy and rates. However, constraints on the effects of SO2‐bearing reactions on basalts with diverse compositions remain incomplete. Here, we present new data from a series of gas‐solid reaction experiments, in which samples of two basalt compositions were reacted in an SO2‐bearing CO2 atmosphere, at relevant Venus temperatures, pressure, and oxygen fugacity. Reacted specimens were analyzed by scanning electron microscopy and scanning transmission electron microscopy using sample cross‐sections produced with focused ion beam milling. Surface alteration products were characterized, and their abundances estimated; subsurface cation concentrations were mapped to show the depth of alteration. We demonstrate that the initial development of reaction products progresses rapidly over the course of 30‐day runs. Alkaline basalt samples are coated by Na‐sulfate (likely thenardite, Na2SO4) and amorphous calcium carbonate (CaCO3) alteration products, and tholeiitic basalt samples are primarily covered by anhydrite (CaSO4), Fe‐oxide (FexOy: likely magnetite, Fe3O4), and other minor phases. These mineralogies differ from previous experiments in CO2‐only atmospheres. Plain Language Summary: Surface features on Venus, such as volcanic landforms, and their ages can be studied to infer the planet's interior properties. Venus' thick, opaque atmosphere and extreme temperature and pressure limit a detailed study of its surface. Fortunately, sensors aboard Venus‐orbiting spacecraft can "see" its surface using select wavelengths of light to provide opportunities to interpret the composition of its surface. However, these interpretations rely on understanding how Venus' atmosphere might chemically interact with the surface and what mineral products may result. This is not yet fully understood despite the results of several prior studies with objectives similar to ours. Here, we share the results from experiments that mimic these chemical reactions. We used rock types such as those known to be on the surface of Venus and subjected them to relevant temperatures and pressure and a blend of two reactive gases, carbon dioxide and sulfur dioxide, to model Venus' atmosphere. After the experiments, we examined the rocks with microscopic instruments that allowed us to characterize chemical changes from their surfaces to their interiors. Our interpretations suggest that these reactions occur rapidly and that the compositions of the mineral coatings produced are dictated by the rocks' slightly different compositions. Key Points: Basalts experimentally altered under Venus P‐T conditions and a CO2–SO2 atmosphere produce reaction products of Ca‐ and Na‐sulfates, and Fe‐oxidesAlteration products and the advancement of alteration were strongly dependent upon the compositions of the solid reactantsThe rates at which basalts altered in a CO2–SO2 atmosphere were greater than rates in a CO2‐only atmosphere [ABSTRACT FROM AUTHOR]

The stratiform and vein-hosted Kapunda Cu deposit in South Australia contains a saprolitized hydrothermal vein with 12.37 wt.% total rare earth oxide (TREO). The vein was analyzed by X-ray diffraction, scanning electron microscopy, synchrotron-based X-ray fluorescence microscopy and electron backscatter diffraction to understand the controls that govern high-grade REE accumulation during periods of intense weathering. Petrological assessments indicate the transformation of an apatite-calcite-aluminosilicate-bearing protolith to a supergene assemblage of Fe-oxides, kaolinite and REE-phosphate minerals that include rhabdophane-(Ce), monazite-(Ce) and florencite-(Ce). This transformation was facilitated by progressive acidification of the weathering fluid, which is indicated by: 1) the increasing crystallinity of authigenic Fe-oxides and kaolinite, which led to REE desorption; 2) the textural evolution and increase in grain size of authigenic REE-phosphates from nanoscopic crystallites, to acicular needles, to micro-scale hexagonal prisms; 3) the late dissolution of REE-phosphates; and 4) the replacement of goethite by jarosite, whose sulfate component originated from the oxidation and weathering of proximal sulfide minerals. Alongside the depletion of pH-buffering carbonate minerals that are indicated by the preservation of calcite menisci, this sulfide dissolution also facilitated acid generation. Results illustrate how highly acidic weathering fluids might facilitate either REE mobilization or REE accumulation in regolith. High-grade REE accumulation under acidic supergene conditions is prioritized when the host-rock contains a significant source of depositional ligands (i.e., phosphate in the form of apatite) that can be readily leached during intense weathering. Exploration companies should therefore assay routinely for REEs in any heavily weathered phosphatic rock, due to the observed efficiency of phosphate minerals as geochemical traps for REE accumulation. [ABSTRACT FROM AUTHOR]

This study aimed to produce polymer-wood composites via in situ polymerization. For this purpose, the polymer-wood composites were manufactured using vacuum in a horizontal autoclave. Physical, mechanical, and durability characteristics were evaluated. The treatments provided significant increases of over 30% and 60% in flexural strength and modulus, respectively. All treatments resulted in lower water absorption and greater dimensional stability of the wood. Furthermore, the treatments altered the surface of the impregnated wood, showing increased surface hydrophobicity, roughness, weather resistance, and modified coloration. Treated woods also exhibited an improvement of over ∼40% in resistance to termite attack. [ABSTRACT FROM AUTHOR]

Cavernous weathering forms have long been studied and discussed as enigmas in geomorphology. Recently, their evolution has been shown to be controlled by moisture patterns, which are still poorly understood. For the first time, capillary water and vapor fluxes were characterized in detail at tafone in a temperate climate of central Europe using a wide range of methods adapted from soil hydrology. Time domain reflectometry showed that moisture flows from the rock interior to the evaporation front in the shallow subsurface of both — the backwalls and the outer surface. When overland flow occurs on the outer surfaces (after heavy rains), 10 mm/day can infiltrate and flow toward the backwalls. The main sources of water for tafone are the influx of water from the rock interior and the infiltration of overland flow after heavy rains, while condensation of air humidity is a minor source. Influx from the rock interior is coupled to the evaporation rate, which varies between 100 and 300 kg/m2/year in summer and less than 15 kg/m2/year in winter. More water evaporates from the backwall of the tafone than from the outer surface, and more salt is deposited in the backwalls, resulting in predominant salt weathering in the backwalls. The tafoni studied thus evolve, and the cavities deepen. Tafoni in arid and semi‐arid environments generally show a much higher contrast between evaporation rates from backwalls and outer surfaces than tafoni and honeycombs in temperate and coastal environments. Tafoni in temperate settings are therefore more susceptible to degradation when evaporation decreases or inflow to the tafone increases. This study also shows that microtensiometers can be used to determine moisture content with high spatial resolution, while time domain reflectometry allows accurate characterization of moisture patterns with depth. [ABSTRACT FROM AUTHOR]

The Araba and Naqus formations in Ras Milan, Sinai, constitute part of the major continuous Paleozoic clastic belt stretching across northern Gondwana. They are sandstone-dominated successions, resting on Precambrian granitic basement, with lowermost thin basal polymictic conglomerate deposits (1–2 m), marking the unconformity. The Araba Formation section is composed mainly of varicoloured violet to reddish brown, fine to coarse-grained laminated and planner and overturned cross-bedded sandstones, while the overlying Naqus Formation is characterized by chaotically distributed poorly sorted quartz pebbles to cobbles within a moderately-sorted coarse- to medium-grained quartz arenite and by abundance and variety of large-scale tabular and trough cross bedding. Modal QFL classification of Araba and Naqus formation sandstones revealed that they are merely quartzose sandstones (quartz arenites). Geochemistry of the succession shows extremely wide compositional ranges for almost all major elements, but the Araba Formation is relatively enriched in SiO2, TiO2, Fe2O3*, Na2O, P2O5, and depleted in Al2O3, MgO, CaO and K2O relative to Naqus Formation. Only the Araba Formation samples are depleted in the transition elements Ni, Cr and Co and oppositely possess extreme enrichment in the HFSEs (i.e. Zr, Hf, Y, Nb, Ta, Th, U), whereas both formations show variable depletion in the LILE Rb, K and Ba, and excessive REE abundances relative to the PAAS and UCC, and LREE-enriched patterns with marked negative Eu anomalies. The provenance of the Naqus and Araba formations could be an earlier felsic magmatic source, which has undergone extensive sedimentary recycling. They possess high compositional maturity and were subjected to intensive to moderate weathering during humid climatic conditions. Passive margin tectonic setting is implied which denotes the derivation of Araba and Naqus formation siliciclastics from stable continental regions or plate interiors and deposition in intracratonic basins. [ABSTRACT FROM AUTHOR]

Weathering processes gradually alter the physical and mechanical attributes of slope materials, weakening the structural integrity and stability of slopes. This paper presents an in-depth analysis of slope stability in an open-pit mine, emphasizing the pivotal role of weathering effects in determining slope stability. To accurately capture the impact of weathering on slope stability, a comprehensive analysis model was developed, incorporating field observations, laboratory testing, and numerical simulations. The effects of weathering on the mechanical properties of black shale were studied through extensive laboratory tests. The uniaxial compressive strength, shear strength, and modulus of elasticity significantly decreased with increasing weathering, indicating a heightened vulnerability to slope failure. The correlation function between mechanical parameters and weathering time was obtained, providing the basis for evaluating the stability of mine slopes. It was found that more severe weathering conditions were strongly correlated with elevated risks of slope failure, including landslides and collapses. Based on these findings, practical recommendations are provided for slope reinforcement and management strategies, aimed at mitigating slope failure risks and ensuring the safe and efficient operation of the mine. By incorporating weathering effects into slope stability analysis, mine operators can make informed decisions that account for the dynamic nature of slope materials and their susceptibility to weathering, thereby improving overall mine performance and safety. [ABSTRACT FROM AUTHOR]

The Yuanjue Grottos are representative of the sandstone grottos in southwest China. The structural stability of their wallrocks has suffered a certain degree of damage, resulting from weathering cavities, which seriously threatens the long-term preservation of these cultural relics. This study utilizes 3D numerical simulation to assess the impact of weathering cavity depth on the structural stability of the grottos. The results reveal that the presence of cavities has led to significant wallrock deformation and settlement, particularly in the front side of the entrance and baseplate area. As the cavity depth increases, the deformation effect intensifies. This study also characterizes the relationship between stress deformation and the distribution of weathered fissures, indicating that joint areas are more susceptible to spalling. Displacement monitoring indicates that the baseplate has experienced uplift, followed by settlement as the cavity depth increases, suggesting an initial phase of elastic deformation followed by plastic and brittle deformation stages, which is consistent with the numerical simulation results. Notably, the baseplate's settlement trend was found to accelerate when the cavity depth exceeded 4 m, with significant changes being observed when the depth exceeded 5 m. Therefore, the depth of the weathering cavity beneath the entrance of the Yuanjue Grottos should be controlled within 5 m, in order to ensure their long-term stability. This research contributes to the understanding of the mechanisms affecting the structural stability of grottos and provides valuable insights for conservation efforts. [ABSTRACT FROM AUTHOR]

Natural stone can undergo disaggregation from various causes, including physical actions such as freeze–thaw cycles, temperature and humidity variations, chemical actions such as the solubilization of minerals by organic and inorganic acids, as well as biological actions due to the colonization of organisms that can produce biocorrosion and biomineralization. This research investigates the impact of microclimatic conditions and microbial activity on the physical and chemical integrity of stone heritage, particularly the biodeterioration caused by fungi in the case of a Romanian rock church. Various analytical techniques were employed, including macroscopic and optical microscopy, Raman spectroscopy, X-ray diffraction, and culture-based identification methods, to characterize the mineral composition and microbial contamination of the rock samples. The analyses revealed that the sandstone consists primarily of quartz (over 90%), muscovite (5–10%), and feldspars. The identified fungi included Cladosporium herbarium, Aspergillus niger, and Mortierella hyalina. The SEM images showed fungal hyphae and spores within the kaolinite–illite matrix, indicating significant microbial colonization and its role in rock deterioration. Additionally, microclimatic data collected over a 12-week period highlighted the substantial fluctuations in temperature and relative humidity within the church, which contribute to the physical and chemical weathering of the stone. This study also noted high levels of particulate matter (PM2.5 and PM10) and volatile organic compounds, which can exacerbate microbial growth and stone decay. The comprehensive analysis underscores the need for targeted preservation strategies that consider both microclimatic factors and microbial colonization to effectively conserve stone heritage sites, ensuring their longevity and structural integrity. [ABSTRACT FROM AUTHOR]

The current study focuses on the degradation rate of polypropylene (PP) and Bauhinia Vahlii (BV) fibers under soil burial and natural weathering conditions for 360 days. The BV‐PP composite was produced with varying BV fiber compositions (0, 10, 20, and 30 wt.%) and 3 % MAPP (Maleic Anhydride Grafted Polypropylene). In addition, MAPP is employed as a coupling agent to improve fiber‐matrix compatibility and promote degradation. The XRD examination shows that a 10 % BV‐PP composite has a crystallinity index of 52.05 %, which is higher than that of neat PP. The rate of biodegradability was investigated using weight loss and tensile properties. The largest degradation was seen in natural weathering conditions with 30 % composite showing the maximum weight loss of 3.8 % and loss in tensile strength and modulus of 16.76 % and 5.11 %, respectively. Simultaneously, no weight loss or drop in tensile characteristics was found in the case of neat PP over 360 days. The SEM images of soil burial show material deterioration, which may be aided by bacterial and fungal activity, whereas natural weathering conditions show a large crack, rougher fracture surface, and cavities, which are attributed to thermal stresses, changes in moisture content, and ultraviolet radiation, thereby promoting the degradation process. [ABSTRACT FROM AUTHOR]

Five decades of monitoring data (1974–2022) at the acidified forested catchment of Langtjern in southern Norway document strong chemical recovery and browning of surface water, related to changes in sulfur (S) deposition. Further recovery is likely to be impacted by future air quality and climate, through catchment processes sensitive to climate change, where the relative importance of these drivers of recovery is poorly known. Here, we explore the importance of the aforementioned drivers for recovery using the well‐established process‐oriented Model of Acidification of Groundwater In Catchments (MAGIC) with historical and projected deposition and climate from 1860 to 2100. New in MAGIC are (i) a solubility control of dissolved organic carbon (DOC) from S deposition, which allows inclusion of the role of organic acids in chemical recovery and (ii) climate‐dependency of weathering rates. MAGIC successfully described observed chemical recovery and browning, and the change toward organic acid dominated acidification status. Hindcasts of pH predicted lower preindustrial pH than previously modeled with MAGIC (simulated without S‐dependency of DOC solubility). Future deposition resulted in limited further recovery. Climate scenarios indicated a substantially wetter future, leading to increased base cation losses and slight surface water reacidification. A sensitivity analysis revealed that a 25%–50% increase of weathering rates was needed to reach preindustrial acid‐neutralizing capacity in 2100, provided S deposition is reduced to a minimum. We predict that the limited chemical recovery from reduced S deposition will be counteracted by climate‐driven reacidification from base cation losses, but that enhanced weathering rates could partly compensate these losses. [ABSTRACT FROM AUTHOR]

Coal extraction in China is increasingly moving towards colder regions such as Xinjiang and Inner Mongolia. However, these mines face land restoration challenges due to a scarcity of fertile topsoil. This study explores the potential of coal gangue, a mining byproduct, as a viable substitute for topsoil. The study examines the effects of humidity fluctuations and freeze–thaw cycles, both individually and in combination, on the weathering disintegration of coal gangue. Coal gangue samples were subjected to controlled laboratory conditions simulating environmental factors. Fourteen interventions were analyzed, and the findings indicated that the combined application of humidity and freeze–thaw cycles significantly accelerated the disintegration process, outperforming the individual interventions. In addition, it was found that significant temperature variations caused the moisture and salts within the gangue to expand, which affected the rate of disintegration. The study showed that the rate of weathering disintegration was significantly higher in conditions of saturated humidity–freeze–thaw cycles compared to unsaturated humidity conditions. This highlights the essential role of ice crystals in accelerating the weathering process during temperature fluctuations. This study highlights the importance of humidity over temperature in the weathering and disintegration of coal gangue. It also suggests that freeze–thaw cycles can enhance this process. The study provides valuable insights for the management and utilization of coal gangue in cold and arid regions. [ABSTRACT FROM AUTHOR]

This study presents the chemical and mineralogical composition of clay deposits and associated rock types within the Ropp Complex in order to assess the influence of parent lithology on the kaolinization, genesis, and utility of the deposit. Representative kaolin samples from E horizons of the weathering profiles and their bedrocks were collected from six sites in the Ropp Complex. Clay mineralogy was determined via the XRD technique, while a geochemical analysis was conducted using XRF, SEM coupled with EDS, and ICP-MS. The results showed that all kaolins dominantly contain kaolinite with a content of 77%–98% except for the AS1 kaolin with only minor kaolinite (20%) but mainly illite (65%). The notably lower crystallinity of kaolinite (HI value of 0.53–1.1) as well as its markedly small grain size is consistent with the formation of kaolinite from intensive chemical weathering of igneous rocks. The AS1 kaolin was probably formed from hydrothermal alteration in the burial stage due to the heating of groundwater by the late volcanism. Mobile trace elements (Sr, Ba, and Eu) exhibited a depletion trend, while immobile elements (Hf, Ta, Th) showed enrichment. The relatively more zirconium in kaolins implies the formation of low-temperature kaolinization. The notably high kaolinite content, accompanied by reasonable levels of Fe2O3 and TiO2, signifies a medium-grade quality. Furthermore, chondrite-normalized rare earth element (REE) patterns exhibit congruent trends in rocks and kaolin samples, indicating a relative enrichment in light rare earth elements (LREEs) alongside a discernible negative Eu anomaly. The abundant kaolinite and silicon–aluminum composition make the kaolins suitable for refractories, pharmaceutics, cosmetics, and supplementary cementitious material (SCM). [ABSTRACT FROM AUTHOR]

Ion-adsorption rare-earth deposits supply over 90% of the global market's heavy rare-earth elements (HREEs). The genesis of these deposits, particularly HREE deposits, has garnered significant attention. To elucidate the metallogenic mechanisms of HREE deposits, a comprehensive study of the weathering profile of granite was conducted in Jiangxi Province, South China. This study focuses on the following two aspects: the petrogeochemistry of HREE-rich granite and the enrichment and fractionation of rare-earth elements (REEs) during the weathering process. The results suggest that the Dabu granites are a typical peraluminous, high-K, calc-alkaline granite series with high silica content (SiO2: 74.5%–76.4%), relatively low phosphorus content (P2O5: <0.05%), and high HREE content (ΣLREE/ΣHREE: 0.16–0.66). Weathering advances the decomposition of minerals and the release of elements. REEs are mainly fixed in the regolith by scavengers, mainly clays, Fe–Mn oxides, and carbonates, and ΣREE can reach 799 ppm in the B horizon. However, HREEs tend to migrate further and preferentially combine with Fe–Mn oxides and carbonates as compared to LREEs, leading to a significant fractionation of REEs in the regolith (ΣLREE/ΣHREE = 0.2–1.1). Additionally, the differential weathering of REE-bearing minerals and the precipitation of secondary REE-bearing minerals are also vital for REE fractionation. [ABSTRACT FROM AUTHOR]

The Cryogenian (ca. 717–635 Ma) snowball Earth glaciations ended with the precipitation of “cap” carbonate successions with negative carbon isotope (δ13Ccarb) values, which have been explained by the addition of various 13C-depleted carbon sources in the deglacial process. These arguments assumed that marine dissolved inorganic carbon (DIC) was enriched in 13C in the synglacial ocean. However, this assumption has not yet been tested, because the synglacial ocean chemistry is unknown. In this study, we carried out detailed analyses of the petrology, carbonate carbon (δ13Ccarb) and oxygen (δ18Ocarb) isotopes, organic carbon (δ13Corg) isotopes, major and minor elemental compositions (Ca, Mg, Mn, Fe, Sr), and iron speciation (total Fe, highly reactive Fe, pyrite Fe) of the carbonate layers (also called synglacial carbonate layers) from the Nantuo Formation (ca. 650–635 Ma) on the Yangtze block, South China. Petrographic observations indicated that the synglacial carbonate comprises dolomicrite, mud-crystal powder dolomite, lime dolomite, and dolomitic limestone, supporting an authigenic carbonate origin, and thus, it potentially recorded the ocean chemistry during the Marinoan ice age. The synglacial carbonate is characterized by extreme Mn enrichment, low Fe/Mn ratios, and low δ13Ccarb (−7‰) values. High Mn contents and low Fe/Mn ratios imply marine redox conditions favoring Mn2+ accumulation and Fe2+ oxidation, while low δ13Ccarb values might be attributed to CO2 degassing of submarine volcanoes as well as low primary burial during the glaciation. Since the δ13CDIC value of the synglacial ocean was lower than the δ13Ccarb values of most cap carbonates, we infer the addition of 13C-enriched DIC or removal of 12C during cap carbonate precipitation, such as through carbonate weathering or organic carbon burial. These findings provide new insights into the nature of Cryogenian glaciation, the origin of cap carbonates, and the aftermath of global glaciation [ABSTRACT FROM AUTHOR]

Salt weathering is a common deterioration phenomenon that affects outdoor cultural properties, and it is important to precisely predict the heat, moisture, and salt transfer in porous materials to suppress salt weathering. Osmosis and osmotic pressure were considered in the field of soil research, especially in clay research, but not in the field of outdoor cultural properties and building materials, which are the main target of salt weathering. Osmosis in clay is supposed to be caused by its surface charge. However, it has been suggested that sandstones and bricks that constitute cultural properties and buildings also have surface charge as clay. Thus, osmosis and osmotic pressure can occur in building materials, which may lead to materials degradation. In this study, we derive basic equations, based on nonequilibrium thermodynamics, for the simultaneous heat, dry air, water vapor, liquid water, cation, and anion transfer in building materials by considering osmosis. This equation was compared with existing model for heat and moisture transfer equations as well as models that considered the salt transfer. Based on the previous research for osmosis in clay, we summarized conditions under which osmosis occurs in building materials and presented an outlook for modeling the physical properties of materials related to osmosis. [ABSTRACT FROM AUTHOR]

The importance of carbonate weathering carbon sinks (CCSs) is almost equal to that of vegetation photosynthesis in the global carbon cycle. However, CCSs have become controversial in formulating carbon neutral policies to deal with global climate problems in various countries, since the carbonate dissolution is reversible. In order to address these controversies, we reviewed recent advances in understanding CCSs and examined the outstanding controversies surrounding them. We have analyzed the five controversies, revealing the existence of CCSs, quantifying their magnitude, clarifying their spatiotemporal pattern, and documenting how they have increased and how they evolved under the background of global change. By addressing these five controversies, we help to bring clarity to the role of CCSs in the carbon cycle of global terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Epoxy-coated reinforcement (ECR), with and without penetrations through the epoxy, was subjected to an accelerated weathering program under ultraviolet (UV) light following Cycle 1 of ASTM G154, simulating outdoor exposure in North America for periods ranging from 1.2 months to 1 year. The corrosion resistance of the bars was evaluated using the ASTM A955 rapid macrocell test. As a control, the corrosion resistance of bars not subjected to the accelerated weathering program was also evaluated. After accelerated weathering equivalent to approximately 1.2 months of outdoor exposure, the corrosion resistance of epoxy-coated bars with penetrations in the coating was reduced, with corrosion losses three to six times greater than ECR without UV light exposure. Even ECR without penetrations through the coating showed a loss in corrosion protection when subjected to the equivalent of 1 year of outdoor exposure. ECR should be stored in a manner that protects it from exposure to UV light. The existing guidelines in ASTM D3963 limiting unprotected exposure to 2 months are not sufficient to protect the coating from damage; limiting exposure to 1 month or less should be required. [ABSTRACT FROM AUTHOR]

In the recent past, several weathering indicators have been developed to describe its state of weathering. The state of rock weathering is a useful indicator to estimate the integrity of tropically weathered rock material and mass which weatherability plays an important role in a tropical region. Through a ground assessment tool, the strength and durability of the rock mass could be estimated and complex or adopted to simplify the early prediction of the complex engineering parameter. This paper presents several models of the Weathering Index (WI) using selected significant parameters using statistical analysis. For this purpose, several sites have been chosen to represent granitic rock mass. Forty (40) numbers of samples were collected and tested comprising from four (4) sites in Malaysia. Several laboratory tests have been conducted such as Point Load Index (Is(50)), dry density, Slake Durability 1 (SD1), Slake Durability 2 (SD2) and moisture content. The field and laboratory data sets are used to determine the WI by using simple regression and MLR analysis Significant parameters found to be useful in determining the WI are selected namely SD1, dry density, Is(50), and block volume. These parameters were selected based on stepwise analysis using Statistical Package for the Social Sciences (SPSS). Following the models' implementation, the models were evaluated and the best prediction model was selected after considering statistical coefficients, such as coefficient of determination (R2), variance account for (VAF), and root mean squared error (RMSE), as well as utilizing a straightforward ranking approach. The findings of this study could contribute to the more accurate prediction of WI using a more simplistic field and laboratory parameters. Therefore, the WI is useful during the initial stages and planning of rock excavation work and provides a good description of weathering grade and rock mass properties, which will affect excavatability in granitic areas. [ABSTRACT FROM AUTHOR]

The study is concerned with the rate of evaporation from porous rock, including the second stage of evaporation characterised by the existence of a dry surface layer separated from the wet capillary zone by a sharp evaporation front. The main objective is to investigate the relationship between the depth of evaporation front and the rate of evaporation as the drying process progresses, and to compare measured evaporation rate with the corresponding calculated values. Sandstone core samples saturated with water were allowed to dry naturally under room conditions, while the changes in the evaporation rate and the depth of evaporation front, among other quantities, were measured. We demonstrate that the evaporation rate can be very accurately determined from the depth of the evaporation front and the ambient air temperature and relative humidity using Fick's law for water-vapor diffusion. During the second stage of evaporation, the diffusion flux through the dry surface layer is computed using the water-vapor diffusion coefficient of the rock, determined from a separate wet cup experiment. In order to cover the first stage of evaporation, an additional parameter characterising the diffusion layer of air above the surface is required, either determined by the best fit to the measured evaporation rates, or adopted from previous studies. The calculated evaporation rate was in good agreement with measurements, with Pearson correlation coefficient 0.98 and relative error of the calculations averaging 15% over the evaporation front depths ranging from 0 to 29 mm. A workflow for determining the evaporation rate from sandstone outcrops is suggested, along with possible applications in sandstone weathering research. [ABSTRACT FROM AUTHOR]

To solve the problem of low resolution of seismic data from granite weathering crust and difficulty in predicting effective reservoir distribution. Based on the research idea of combining geology and seismology, seismic facies characteristics and effective reservoir distribution of granite weathering crust are studied by means of frequency division reconstruction processing, seismic facies analysis and sensitive attributes interpretation. This method consists of the following four main processes: (1) Using improved Morlet wavelet function for frequency division and reconstruction processing of seismic data; (2) From the perspective of geological evolution, analyzing the geological origin of seismic facies; (3) Based on the results of well- seismic combination, clarifying the types of effective reservoirs and predicting their distribution; (4) Comprehensive research indicating favorable reservoirs distribution. The results indicate that (1) a considerably improved resolution of seismic data processed by frequency division reconstruction is obtained based on the improved Morlet wavelet function. Thus, granite reservoirs then have clearer internal reflection characteristics. (2) Affected by differences in weathering, the seismic facies in granite weathering crusts can be classified as follows: Strong-amplitude facies with amplitudes of 23,700 − 32,800, corresponding to eluvium, represents the late stage of weathering crust evolution with high-intensity weathering. Medium-amplitude facies with amplitudes of 5,250 − 24,000, corresponding to dissolution layer, represents a middle stage of weathering crust evolution with moderate weathering. And weak-amplitude-blank facies with amplitudes of 0–5,330, corresponding to disintegration layer, represents an early stage of weathering crust evolution with weak weathering. (3) Effective reservoirs can be classified according to well-seismic calibrations and combined with reservoir spaces, porosities and permeabilities, and the logging and oil-bearing characteristics of the reservoirs. Type I effective reservoir comprises medium-amplitude facies, with favorable reservoir conditions and high-yield oil-bearing properties; this type is distributed in the western slopes, with an elevation of 1,300-2,500 m. Type II effective reservoir comprises strong-amplitude facies, with poor oil-bearing properties; this type is mainly distributed in the southeast and north slopes of the study area, with a relatively limited range, and the elevation is mostly below 1,500 m. Type III effective reservoir comprises weak-amplitude-blank facies, with poor reservoir conditions and poor oil-bearing properties; this type is widely distributed at various elevations. (4) The areas where medium-amplitude facies have developed are the most favorable reservoir exploration zones for granite in Dongying Sag, Bohai Bay Basin. [ABSTRACT FROM AUTHOR]

The hydrochemical characteristics of watersheds are influenced by many factors, with chemical weathering and human activities exerting the most substantial influence. Performing a quantitative evaluation of the factors contributing to the chemical weathering of rocks is of significant scientific importance. This research zeroes in on the Qingtang River basin to elaborate on the hydrochemical characteristic, explore the origins of ions, and quantify the influence of anthropogenic discharges amidst cation interferences, thus improving the accuracy of chemical weathering rate estimations. The samples encompassed surface water, groundwater, and water from dripping in karst caves. The findings indicate that human-induced alterations significantly influence hydrogeochemical dynamics, although chemical weathering of rocks in their natural state is the controlling factor. The mean contributions of cations from atmospheric deposition, human inputs, carbonate weathering, and silicate weathering were 17.56%, 21.05%, 51.77%, and 9.54%, respectively. The chemical weathering rate for carbonate rocks was 62.4 t·km−2·a−1, which increased by 27.87% due to the influence of exogenous acids. The anthropogenic impact is predominantly evident in two aspects: (1) the alteration of hydrochemical processes within the watershed through direct input of ions, and (2) the acceleration of rock weathering rates in the watershed due to the exogenous acids. [ABSTRACT FROM AUTHOR]

This article examines the clay mineralogy of twelve representative soils developed from gypsum-rich parent materials on several geomorphic positions. These soils were classified as Haploxerept, plus one profile as Humixerept and another as Xerorthent. The clay mineralogy, determined by X-ray diffraction, showed quite a similar clay composition in all profiles, with mica, chlorite, and smectite, from most to less abundant. Mica and chlorite are deemed inherited, while smectite—appearing in minor proportions—could result from both transformation and/or neoformation, because the leaching of bases by free drainage does not favor the transformation of mica to smectite. Therefore, the differences in clay mineralogy appeared to be lithogenic rather than pedogenic. These compositional data are an advance in the basic knowledge of the studied soils. [ABSTRACT FROM AUTHOR]