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This study aims to investigate the combined use of multi-sensor datasets (Landsat 4–5 & 8 OLI satellite imagery, spatial resolution = 30 m) coupled with field studies to evaluate spatio-temporal dynamics of soil salinization along the coastal belt in West Bengal, India. This study assesses soil salinization by mapping the salinity and electrical conductivity of saturation extract (EC_e) and utilizing spectral signatures for estimating soil salinity. The SI change (%) was analyzed (2021–1995), categorizing increases in salinity levels into 5%, 10%, and 50% changes possibly due to salt encrustation on the soil layers. The land use land cover (LULC) change map (2021–1995) demonstrates that the study area is continuously evolving in terms of urbanization. Moreover, in the study area, soil salinity ranges from 0.03 ppt to 3.87 ppt, and EC_e varies from 0.35 dSm⁻¹ to 52.85 dSm⁻¹. Additionally, vulnerable saline soil locations were further identified. Classification of soil salinity based on EC_e reveals that 26% of samples fall into the non-saline category, while the rest belong to the saline category. The Spectral signatures of the soil samples (n = 19) acquired from FieldSpec hand spectrometer show significant absorption features around 1400, 1900, and 2250 nm and indicate salt minerals. The results of reflectance spectroscopy were cross-validated using X-ray fluorescence and scanning electron microscopy. This study also employed partial least square regression (PLSR) approach to predict EC_e (r² = 0.79, RMSE = 3.29) and salinity parameters (r² = 0.75, RMSE = 0.51), suggesting PLSR applicability in monitoring salt-affected soils globally. This study’s conclusion emphasizes that remote sensing data and multivariate analysis can be crucial tools for mapping spatial variations and predicting soil salinity. It has also been concluded that saline groundwater used for irrigation and aqua-cultural activities exacerbates soil salinization. The study will help policymakers/farmers identify the salt degradation problem more effectively and adopt immediate mitigation measures.

The occurrence of massif-type anorthosite intrusions is a widespread Proterozoic phenomenon. They are usually associated with gabbroic, charnockitic, and granitic rocks, comprising the so-called anorthosite-mangerite-charnockite-granite (AMCG) suite. Although these rocks have been extensively studied worldwide, several aspects concerning their formation remain unsettled. Among them, the magma source and the tectonic setting are the most important. To evaluate these issues, we first compiled geochemical and isotopic data of Proterozoic anorthosite massifs and AMCG suites worldwide and stored it in a database named datAMCG. This plethora of data allows us to make some important interpretations. We argue that the wide-ranging multi-isotopic composition of this group of rocks reflects varying proportions of juvenile mantle-derived melts and crustal components. We interpret that the precursor magmas of most massive anorthosite bodies and associated mafic rocks have a mantle-dominated origin. However, we highlight that a crustal component is indispensable to generate these lithologies. Adding variable amounts of this material during succeeding multi-stage assimilation-fractional crystallization (AFC) processes gives these intrusions their typical mantle-crustal hybrid isotopic traits. In contrast, a crustal-dominant origin with a complementary mantle component is interpreted for most MCG rocks. In summary, the isotopic information in datAMCG indicates that both sources are necessary to generate AMCG rocks. Therefore, we suggest that hybridized magmas with different mantle-crust proportions originate these rocks. This interpretation might offer a more nuanced and accurate depiction of this phenomenon in future work instead of choosing a single-sourced model as in the past decades. Finally, tectonomagmatic diagrams suggest that the rocks under study were likely generated in a tectonic environment that transitioned between collision and post-collisional extension, sometimes involving subduction-modified mantle sources. This interpretation is supported by geological and geochronological information from most complexes, thus challenging the Andean-type margins as an ideal tectonic setting.

The unique ore-forming processes and the key factors responsible for formation of skarn deposits are still obscure, and challenges exist in the determination of timing of Pb-Zn skarns owing to lacking suitable mineral chronometers. Here we present detailed paragenesis, bulk geochemistry, in situ U-Pb dating of zircon and garnet, and garnet oxygen isotopes together with in situ zircon Hf-O isotopes from the newly discovered Aqishan Pb-Zn deposit in the southern Central Asian Orogenic Belt (CAOB), northwest China. This comprehensive data set revealed a Late Carboniferous subduction-related distal Pb-Zn skarn system associated with the granitic magmatism. Pre-ore stage garnets are generally subhedral to euhedral with oscillatory zoning and show slightly fractionated rare earth element patterns with positive Eu anomalies that point to an infiltration metasomatism origin under high water/rock ratios. The syn-ore stage sphalerite is typically enriched in Mn and Cd and has moderate Zn/Cd ratios (337–482), with a formation temperature of 265 °C to 383 °C, which indicate magmatic-hydrothermal signatures. The isocons defined by P₂O₅ decipher that the principal factors for skarn formation were elevated activities of Fe, Ca, and Si species, where remobilization of Pb metals, meanwhile, contributed to ore-forming budgets to mineralizing fluids. SIMS U-Pb dating of zircons from granite porphyry that occurs distal to the skarns and Pb-Zn orebodies shows that these intrusions emplaced at ca. 311.3–310.6 Ma, recording the subduction of the Paleo-Tianshan oceanic plate. Hydrothermal garnets in close textural association with Pb-Zn sulfides yield indistinguishable in situ LA-ICP-MS U-Pb ages of 310.5 ± 4.1 Ma. Whole-rock geochemistry and in situ zircon Hf-O isotopes (δ¹⁸O = 4.6‰–6.0‰) indicate that the granite porphyry was derived from partial melting of juvenile crust and influenced by subducted oceanic crust. Oxygen isotope compositions of garnets (δ¹⁸O = 8.0‰–9.0‰) demonstrate that the equilibrated ore fluids were inherited from fluid-rock interactions between a primary magmatic water and host tuff rocks. Our study highlights the application of garnets as a potential robust U-Pb geochronometer and isotopic tracer of ore fluids in skarn mineralizing systems in subduction-related arc environments.

The impact of hydro energy production, economic complexity, urbanization, technological innovation and financial development on environmental sustainability between 1995 and 2017 is examined for a panel of thirteen Asian economies using two environmental proxies— their ecological footprint and CO₂ emissions. The non-parametric Driscoll-Kraay standard error method and the Dumitrescu-Hurlin panel causality test are applied to the data. Our findings show that hydro energy production and technological innovation have a significant negative impact on the environment, thus promoting environmental sustainability. Economic complexity significantly lowers environmental sustainability while the non-linear effect of economic complexity favors environmental sustainability; this confirms the existence of an economic-complexity-based inverted-U-shaped environmental Kuznets curve hypothesis. Moreover, urbanization and financial development significantly decrease environmental sustainability. The results of our study confirm the feedback causality between hydro energy production and carbon dioxide emissions. We recommend expansionary policies regarding hydro energy production that are beneficial for substituting fossil fuel energy. This paves a path towards environmental sustainability in this era of global boiling.

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline province. Dolomite carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce) and bastnäsite-(Ce). Ancylite was previously shown to have probably formed in the Devonian (ca. 365 Ma) during an early postmagmatic overprint. Previous geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the mineralization. The in situ U-Pb dating of bastnäsite allowed us to constrain its genesis. Bastnäsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by (1) quartz-bastnäsite and (2) strontianite aggregates (hereafter bastnäsite-rich and strontianite-rich carbonatites – BRC and SRC, respectively). The obtained age estimations (237.7 ± 9.8 Ma and 239.9 ± 4.1 Ma, respectively) indicate that both studied rocks were formed during a single event. The revealed age difference (∼125 Ma) excludes the genetic link between the bastnäsite origin and regional alkaline magmatism, pointing out an additional source for the Vuoriyarvi bastnäsite-bearing rocks. Moreover, the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich carbonatites. Most of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite, while strontium was transported and incorporated into strontianite. The Pb isotopic characteristics of bastnäsite (²⁰⁶Pb/²⁰⁴Pb = 18.1 ± 0.1, ²⁰⁷Pb/²⁰⁴Pb = 15.3 ± 0.1, and ²⁰⁷Pb/²⁰⁶Pb = 0.84 ± 0.01) are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic overprint. Isotopic signatures of Pb, Sr, and Nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline complex. Taken together, the results of the present study negate the supergene origin of the Vuoriyarvi bastnäsite, implying that the bastnäsite mineralization is not confined to near-surface layers and, therefore, may be dispersed more broadly throughout the complex. These findings raise the question on underestimation of the probable REE reserves and lay the groundwork for a reassessment of the economic potential of the Vuoriyarvi complex.

Natural resource management is indispensable keeping in view their positive economic impacts as well as their detrimental environmental consequences. To achieve certain SDGs, it is inevitable to manage natural resources through effective policies that help to inhibit adverse environmental impacts. Based on this approach, the current empirical analysis aims to probe whether environmental policy stringency intensifies, meagres, and/or halts the abysmal environmental impact of natural resources in G-7 countries (United Kingdom, United States, Canada, Italy, France, Japan, and Germany) for the period from 1990 to 2020. To that end, we rely on the second-generation panel data approaches and panel quantile regression. The outcomes reveal that natural resources increase carbon dioxide emission whereas the synergy of natural resources and environmental policy stringency plunges emissions across the quantiles. These findings suggest adoption of a strict environmental policy for attaining the targets of SGD-08 (economic growth), SDG-09 (innovations), SDG-11 (sustainable cities), SDG-12 (responsible consumption of natural resources), and SDG-13 (climate action).

⁴⁰Ar-³⁹Ar geochronology, geochemistry, and Sr-Nd isotopic compositions of 30 core samples from 24 offshore drill wells in the Western offshore basins have been used to characterize the genetics of the volcanic basement from the Kutch, Mumbai, and Kerala-Konkan offshore basins. Findings from the volcanic basement rocks demonstrate extremely varied isotopic and geochemical fingerprints, which are suggestive of significantly diverse parent magma compositions and emplacement processes.

Basaltic tholeiitic basement from Kutch Offshore basin has Ar-Ar ages that range between 60 Ma and 62 Ma. This basement is characterised by a within-plate basalt signature, with depleted isotopic signatures similar to least contaminated Deccan Traps basalts, and a component of subducted crustal material. Basaltic basement from Mumbai Offshore Basin has eruption ages between 63 Ma and 65 Ma and show a strong within-plate OIB affinity. Geochemical and isotopic signatures are consistent with Renuion lavas and an enriched-end member of Deccan Traps basalts. However, Kerala-Konkan Offshore Basin shows significant E-MORB affinity and is characterized by primitive-mantle signatures and least contamination from the upper continental crust, with ages of eruption between 60 Ma and 61 Ma based on obtained ⁴⁰Ar-³⁹Ar ages.

The study suggests that the Mumbai Offshore Basalts’ mode of the eruption was comparable with onshore Deccan volcanism, whereas the basaltic basement in Kutch Offshore was formed after the main phase of Deccan eruption and may have been an offshoot of a “tail” of the main Deccan volcanism. The parent magma for the volcanic E-MORB basement in the Kerala-Konkan Offshore Basin is thought to have come from mixing along the Carlsberg Mid-Oceanic Ridge and the material from the Réunion plume with the northward movement of the Indian Plate during the Early Paleocene. This is thought to have occurred concurrently with the formation of the Chagos-Laccadive Ridge.

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species. However, existing methods often rely on the presence of complete eggs and embryo remains, and sedimentological criteria that are only applicable to well-structured sediments. In this study, we introduce an innovative approach to characterize egg accumulations in structureless sediments, where traditional nest structures may not be preserved. Our methodology employs a unique combination of sedimentological, taphonomic, geochemical, and geophysical proxies for the study of egg accumulations. We applied this approach to the egg accumulation from Paimogo (Jurassic, Portugal), traditionally interpreted as a nest. Our findings reveal that the Paimogo egg assemblage is a secondary deposit, resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph clutches. The eggshell vapor conductance results, coupled with sedimentological evidence, suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season, likely during the dry season to prevent the embryos from drowning. This research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless sediments. Our findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms, contributing to our understanding of dinosaur ecology.

The energy access challenge remains a significant barrier to sustainable development, with millions of people still needing access to modern energy services. Fossil fuels have played a crucial role in meeting electricity demand, but they face challenges and drawbacks in terms of environmental sustainability, energy security, and climate change. This study examines how renewable and non-renewable energy generation capacity impacted the environment in 53 upper-middle-income countries from 1990 to 2020, using energy access and alternative energy sources as mediating variables. The findings of this study provide valuable insights into the complex relationship between renewable energy generation capacity, energy access, alternative energy sources, and environmental conditions in upper-middle-income countries. The positive relationship between renewable energy generation capacity and environmental conditions emphasizes the importance and potential of renewable energy sources in mitigating environmental degradation. Additionally, the findings indicate that energy access also plays a crucial role in shaping energy generation patterns, with higher levels of access being associated with increased renewable energy generation and decreased reliance on non-renewable energy sources. These findings highlight the urgent need for policies and measures to promote renewable energy adoption and prioritize energy access to mitigate environmental degradation and achieve sustainable development goals.

Phosphorus is one of the key elements, which determined the emergence of primordial life on our planet. The source of prebiotic phosphorus was most likely to be easily soluble compounds containing phosphorus in the negative form of oxidation (e.g., phosphides). The present paper is the first thorough investigation of phosphide-bearing mineral assemblages confined to telluric (terrestrial) native iron from volcanic rocks of Disko Island, Greenland. Phosphorus speciation in given assemblages varies from the solid solution in native iron (up to 0.3 wt.% P), different phosphides – schreibersite Fe₃P, nickelphosphide Ni₃P, barringerite Fe₂P, and phosphates, including fluorapatite, anhydrous Fe-Na phosphates, phosphoran olivine and pyroxene (up to 1 wt.% P). The diversity of observed phosphorus speciation can be explained by the steep changes of redox conditions during subsurface crystallization of iron-phosphide-bearing lavas. Based on the available data on likely redox conditions on the early Earth, we hypothesize that reactive prebiotic phosphorus may have originated from shallow crustal rocks.