Geological Journal最新文献

The rapid use of electrical and electronic devices due to their wide applications in various fields produces a large amount of e-waste (electronic waste) in the modern world. To overcome this problem, there is a need to recycle the used product into useful products from e-waste. Therefore, this approach is essential for the development of advanced technologies for the recovery and separation of REEs (rare earth elements) from e-waste. Here, REEs are sometimes referred to as the “vitamins” of the modern industry. E-waste can contribute significantly to REE pollution since it is frequently handled hazardously and contains high amounts of REEs. Apart from the harmful effects on the environment, these wastes also destroy precious materials such as gold, silver, copper, platinum, palladium, and rare earth elements. Every year, 50 million tons of e-waste is generated worldwide. A large amount of e-waste goes to waste as only 20% of it is handled properly worldwide. The various approaches, including bioleaching, biosorption, siderophores, pyrometallurgical, and hydrometallurgical processes, have been reported in numerous studies on the recovery and separation of rare earth elements (REEs) from electronic waste. This review paper provides an overview of the introduction, characteristics, sources, and applications of clean and green energy technologies. The current pathways for REEs production and recovery point out significant deficiencies in methods currently in use and emphasise areas where multidisciplinary research may lead to more practical solutions. A summary also provides the impact of e-waste on health and the environment. The challenges, research gap, and future directions and suggestions are reported at the end of this review paper.

Shale oil and gas, as an essential type of unconventional oil and gas resources, and compressibility is one of the most critical aspects of shale oil and gas exploration and development. Elastic parameters have a significant impact on the compressibility of shale. Montmorillonite is one of the typical clay minerals in shale, and its microstructure has unique characteristics. When encountering water underground, it is effortless to expand. Therefore, the study of the mechanical properties of montmorillonite is crucial. This study is based on molecular dynamics simulation to establish Na-montmorillonite with different hydration degrees, change its temperature and pressure, conduct comprehensive research and comparison by combining the elasticity parameter of montmorillonite with different hydration degrees, and explain the micro mechanism of its impact. Simulation results display that the mechanical properties of hydrated montmorillonite are negatively correlated with temperature. There is a positive correlation with pressure. As the degree of hydration increases, the mechanical properties of montmorillonite decrease. The mechanical properties of montmorillonite are anisotropic. The factors that play a leading role in the stage of temperature, pressure and hydration degree under micro and macro conditions are studied. This research achievement has guiding significance for the comprehensive understanding of montmorillonite and the elastic parameters of shale at the micro level.

This review presents new insights on the origin of primary arc magma and its geochemical signatures in the Barren Island and Narcondam using Arc Basalt Simulator 5 (ABS5). Barren Island rocks are basalt to basaltic andesite showing tholeiitic composition, while Narcondam is mostly andesite showing calc-alkaline composition. ABS5 indicates that slab dehydration and P–T conditions were similar, and slab liquid uptake was highest from the altered oceanic crust, followed by sediment and mantle wedge coupled to slab top. Unlike trace elements, the ⁸⁷Sr/⁸⁶Sr–¹⁴³Nd/¹⁴⁴Nd ratios of the slab liquid show a depleted signature in Barren Island compared with Narcondam, due to R% (reactivity between solid and liquid in the slab). The initial mantle composition in the Barren Island and Narcondam indicates prior melt extraction of < 0.5%–1.5%. Barren Island shows lower β% (fraction of slab liquid in the partial melt) than Narcondam. The H₂O content in slab liquid was slightly higher in Barren Island (7.3–8.6 wt%) than Narcondam (5.5–6.8 wt%). Accordingly, the degree of partial melting (F = 10.9%–20.20% in Barren Island, F = 5.3%–10.5% in Narcondam) and total melt productivity (%) were higher in Barren Island compared with Narcondam. ABS5 indicates that the slab liquid contributed LILE, LREE, Th, U and ⁸⁷Sr/⁸⁶Sr-¹⁴³Nd/¹⁴⁴Nd, while the mantle melts contributed HFSE, MREE, HREE, Y¹⁴³Nd/¹⁴⁴Nd in Barren Island and Narcondam. ABS5 indicates that the total melt production (%), H₂O content in slab liquid and mantle wedge were higher in post-caldera than in pre-caldera rocks.

As hydrocarbon exploration progresses in the Santanghu Basin, tight oil reservoirs in Carboniferous volcanic rocks have become a focal point for exploration and development efforts. This study aims to account for significant industrial oil flow from the tight tuff layers of the Kalagang Formation in well blocks Ma 71 to 33 in the Malang Sag within the basin. Through experiments including organic carbon analysis, rock pyrolysis, and nuclear magnetic resonance (NMR), this study systematically investigated the principal characteristics and determinants of the tight oil reservoirs, culminating in the development of hydrocarbon modes, thus providing a reference for tight oil exploration and production in the study area. The results indicate that the Kalagang Formation is composed predominantly of tuff, especially vitric tuff. The storage spaces of this formation include dissolution pores, tectonic fractures, and dissolution fractures, with devitrification pores less common. Compaction plays a crucial role in rendering the tuff reservoirs tight. Nevertheless, differentiated diagenetic alterations have improved the microscopic storage spaces and their interconnectivity. Well blocks Ma 3301 and Ma 33, having undergone significant weathering (leaching), exhibit superior reservoir physical properties and connectivity compared to well blocks Ma 71 and Ma 73. In contrast, well blocks Ma 71 and Ma 73 experienced more significant alterations due to organic acid dissolution and devitrification under the influence of source rock types and hydrocarbon generation. The comprehensive analysis indicates that tight oil reservoirs in the Malang Sag were formed due to the close superimposition of source rocks and reservoirs, along with the effective connection of source rock-rooted faults. This results in the formation of two sets of proximal tight tuff reservoirs with the ‘lower-source rock and upper-reservoir’ and ‘self-sourced reservoir’ modes.

Narmada-Tapi dyke swarm is one of the two principal swarms within the Deccan Volcanic Province of India. This study presents new data on the field characters, geometry, and structure of mafic dykes of this giant swarm, housed in a mid-continental fault zone of Precambrian heritage mimicking horst-graben structure. We map 443 lineaments as dykes in an area of 7000 km² and validate 193 on ground. The braided map pattern in the swarm's densest parts indicates higher rates of fracture propagation and magma flow (movement) duly manifested by occasional incorporation of basement xenoliths and local contact-melting of host basalt lava flows. During dyke emplacement, the principal stress axes made a prolate ellipsoid (σ1 >> σ2 > σ3) and the 3D Mohr's stress circles related the magma pressure (P_m) to the paleo-stress regime as σ2 > P_m > σ3. The swarm induced ~5% crustal extension. We estimate magma overpressure that drove the dyke-melt upwards and laterally through the fractured granitic basement from ~10 to 12 km deep magma chamber, assisted by hydro-fracturing of older basaltic flows at shallow levels. We also review the significance of the regional fault-bounded dyke swarms in the emplacement of Deccan flood basalts.

The mantle beneath the Mariana subduction zone is commonly described as depleted, primarily composed of peridotite. This study aims to investigate whether subduction processes influence the lithologic characteristics of the mantle source beneath the Mariana subduction zone. We conducted a comprehensive analysis of olivine elemental compositions from basalts in different subduction settings in the Mariana region, including the island arc, back-arc and initial arc rifting stages. Analysis of major and trace elements in olivines, as well as key elemental ratios (e.g., 10,000 × Zn/Fe, Mn/Zn and 100 × Mn/Fe), reveals that olivines from different subduction settings exhibit characteristics consistent with a peridotite source. While Ca content varies significantly among samples, olivines with high Fo values (Fo > 87) and high Ca contents are consistent with peridotite characteristics. In contrast, olivines with low Fo values (Fo < 87) exhibit lower Ca contents, reflecting the characteristics of a pyroxenite mantle source. This discrepancy is attributed to slab subduction, which increases water content in the mantle wedge and facilitates greater incorporation of Ca into the melt. The compositional distributions of Mn in olivines indicate distinct partitioning behaviours under varying pressure and temperature conditions, with Mn concentrations being particularly sensitive to pressure variations. Therefore, the variation in Mn composition reflects the different pressure conditions experienced by peridotite during its evolution. In different tectonic settings, the variation in Ni contents is mainly controlled by magmatic evolution, with minimal influence from temperature and pressure. Despite the differences in elemental content, our results demonstrate that the mantle source region in the Mariana subduction zone, whether in the island arc, back-arc basin or initial arc rifting, consistently consists of peridotite, with no different results arising from variations in the subduction processes.

Attaining a firm slope stability analysis holds eminent importance in civil and geotechnical projects. This study is concerned with the indirect assessment of the stability of slopes using improved versions of artificial neural networks (ANN). Two novel metaheuristic techniques, namely the seeker optimization algorithm (SOA) and the electromagnetic field optimization (EFO) are employed for optimising the ANN that aims at predicting the factor of safety (FOS). Two hybrids of EFO-ANN and SOA-ANN, as well as a single conventional ANN, are trained and tested using a valid dataset collected from the earlier literature. First, examining the importance of the input factors showed that the unit weight of slope material (γ) is the most important one, followed by internal friction (ϕ), average angle of slope (β), cohesion (c), the height of slope (H), and pore water pressure coefficient (r _u ). Upon monitoring the performance of the ANN, this model stops training after some epochs because of the divergence in the solution, whereas this issue was resolved by the EFO and SOA in hybrid models. Consequently, significant improvements were achieved in both training and testing accuracies. By comparison, while the EFO-ANN was more successful in the training task, the SOA-ANN presented the most reliable prediction of the FOS. The prediction competency of these models is also verified through (a) comparison with earlier literature and (b) applying them to another real-world dataset for binary prediction of slope stability/failure. An explicit predictive formula is derived from the SOA-ANN, which is recommended as a convenient approximator of FOS in slope stability analysis.

The increasing frequency and severity of climate-induced disruptions necessitate robust methodologies for assessing regional resilience. This study introduces a hybrid analytical framework integrating the Analytic Network Process (ANP), Artificial Neural Networks (ANN) and PROMETHEE-GAIA to systematically evaluate climate resilience across Chinese provinces. Resilience is assessed through three dimensions: exposure, sensitivity and adaptive capacity, each comprising multiple sub-criteria informed by expert inputs and literature review. ANP models the interdependencies among resilience factors, while ANN validates the assigned weights, ensuring methodological robustness. PROMETHEE-GAIA ranks provincial resilience levels, providing insightful visualisations of resilience trade-offs. The findings reveal substantial regional disparities: coastal provinces such as Jiangsu and Zhejiang exhibit higher resilience due to advanced infrastructure, economic robustness and effective governance, while inland regions like Qinghai and Gansu demonstrate heightened vulnerabilities due to limited adaptive capacity and economic dependencies on climate-sensitive sectors. The study provides a replicable framework for resilience assessments globally, offering actionable insights for policymakers to enhance climate adaptation strategies and equitable resource allocation.

In recent years, extensive oil and gas exploration in the Ordos Basin has led to the discovery of oil reservoirs within the Carboniferous Yanghugou Formation in the basin's southwestern margin. This study investigates the organic geochemical characteristics and oil-source correlations in the Yanghugou Formation, aiming to clarify the origin of crude oil in this formation by comparing samples from both the Yanghugou and Wulalike formations. Geochemical analyses reveal that the Yanghugou Formation source rocks exhibit high organic matter content, low maturity, and a freshwater-oxidising environment, with contributions from both land plants and aquatic organisms, suggesting significant potential for oil generation. Conversely, the Wulalike Formation source rocks exhibit lower organic matter content, higher maturity, and a brackish water-weakly reduced environment, reflecting a more moderate oil-generating potential. The study uses biomarkers and multivariate statistical methods, including cluster analysis and Q-factor analysis, to establish that the oil in the Yanghugou Formation is a mixed-source oil, originating from both the Yanghugou and Wulalike source rocks. The results highlight the importance of combining geochemical parameters and statistical techniques to improve oil-source correlations and aid exploration strategies in the southwestern Ordos Basin. This study provides new insights into the complex hydrocarbon accumulation mechanisms in the area and offers valuable information for future exploration efforts.