Geosciences

19 pages, 6446 KB

Open AccessArticle

Fluorapatite from a Pegmatite with Miarolitic Cavities in the Larsemann Hills, East Antarctica: ID-TIMS U-Pb Ages and LA-ICP-MS Trace-Element Constraints on the Late Pan-African Orogenic Evolution

by Ivan A. Babenko, Nailya G. Rizvanova, Sergey G. Skublov, Yuri A. Bishaev, Irina V. Talovina, Olga L. Galankina and Alexander V. Kuznetsov

Geosciences 2026, 16(3), 133; https://doi.org/10.3390/geosciences16030133 - 23 Mar 2026

Viewed by 319

Abstract

Pegmatites with miarolitic cavities have not previously been reported from the Larsemann Hills, East Antarctica, and their age and origin remain poorly constrained. We report the first geochemical and geochronological data for fluorapatite from a newly discovered pegmatite with miarolitic cavities in the [...] Read more.

Pegmatites with miarolitic cavities have not previously been reported from the Larsemann Hills, East Antarctica, and their age and origin remain poorly constrained. We report the first geochemical and geochronological data for fluorapatite from a newly discovered pegmatite with miarolitic cavities in the Larsemann Hills. Large Fe-rich fluorapatite crystals (up to 5 cm) contain abundant oriented monazite-(Ce) inclusions and display elevated REE (1397–7966 ppm), relatively high Y (945–4192 ppm), and low Sr (52.2–83.5 ppm). Their trace-element signatures plot within the fields of partial melts, high-grade metamorphic rocks, and evolved fluid-rich magmatic systems. U–Pb dating of fluorapatite yields concordant ages of 519 ± 4 Ma (ID-TIMS) and 521 ± 31 Ma (LA-ICP-MS), indicating crystallization during the D₄ stage of the Pan-African orogeny. The isotopic equilibrium between apatite and monazite inclusions suggests synchronous formation and late-stage fluid overprinting. Combined geological, geochemical, and isotopic evidence shows that the pegmatite formed in situ as a product of anatexis of the Broknes paragneisses and evolved within a volatile-rich magmatic–hydrothermal system. These results provide the first direct age constraints on pegmatites with miarolitic cavities in Antarctica and shed new light on the final stages of East Gondwana assembly. Full article

(This article belongs to the Section Geochemistry)

► Show Figures

Figure 1

24 pages, 23496 KB

Open AccessArticle

Shear Behavior and Strength Model for the Ice-Rock Interface with Different Roughnesses

by Shipeng Hu, Tiantao Li, Weiling Ran, Jian Guo, Shihua Chen, Jing Yuan and Hao Jing

Geosciences 2026, 16(3), 132; https://doi.org/10.3390/geosciences16030132 - 23 Mar 2026

Viewed by 257

Abstract

The ice–rock interface shear mechanism is fundamental to understanding ice–rock avalanche hazards. This study conducts a series of direct shear tests under various normal stresses to analyze the mechanical response and acoustic emission (AE) evolution of the interface, establishing a shear strength prediction [...] Read more.

The ice–rock interface shear mechanism is fundamental to understanding ice–rock avalanche hazards. This study conducts a series of direct shear tests under various normal stresses to analyze the mechanical response and acoustic emission (AE) evolution of the interface, establishing a shear strength prediction model. Results indicate that the roughness significantly affects mechanical properties and AE responses: as the roughness increases, the shear strength, cohesion, and internal friction angle improve significantly, while peak AE ringing counts and energy exhibit an increasing trend. During failure, the proportion of shear cracks decreases while tensile cracks increase, reflecting a shift in crack development modes driven by the roughness. Based on AE characteristics and stress–displacement relations, the shear failure process is categorized into five stages: initial, crack development, crack propagation, crack coalescence, and residual stages. Incorporating the effects of the roughness and cementation force, a shear mechanical model was established. Experimental data verify the model’s rationality; however, its applicability may be limited when the roughness is excessively high. Full article

(This article belongs to the Special Issue Editorial Board Members' Collection Series: Natural Hazards)

► Show Figures

Figure 1

38 pages, 256826 KB

Open AccessArticle

Ediacaran Fluviolacustrine Depositional Systems of the Amane-n’Tourhart and Tifernine Basins (Anti-Atlas, Morocco): Facies Analysis, Petrography, Paleoenvironments, and Climatic–Volcanic Controls

by Jihane Ounar, Hicham El Asmi, Mohamed Achraf Mediany, Rachid Oukhro, Kamal Mghazli, James Pierce, David A. D. Evans, Malika Fadil, El Hassane Chellai, Moulay Ahmed Boumehdi, Nasrrddine Youbi, Timothy W. Lyons and Andrey Bekker

Geosciences 2026, 16(3), 131; https://doi.org/10.3390/geosciences16030131 - 23 Mar 2026

Viewed by 644

Abstract

This study provides sedimentological and stratigraphic insights into the Ediacaran fluviolacustrine successions of the Amane-n’Tourhart and Tifernine basins. The Amane-n’Tourhart Basin developed in a post-caldera volcanic setting along the margin of the Oued Dar’a Caldera, whereas the Tifernine Basin formed in a pre-caldera [...] Read more.

This study provides sedimentological and stratigraphic insights into the Ediacaran fluviolacustrine successions of the Amane-n’Tourhart and Tifernine basins. The Amane-n’Tourhart Basin developed in a post-caldera volcanic setting along the margin of the Oued Dar’a Caldera, whereas the Tifernine Basin formed in a pre-caldera tectono-volcanic context associated with caldera development. The successions provide valuable information about the sedimentary processes operating in late Ediacaran continental environments. Field observations, facies analysis, and petrography reveal a variety of siliciclastic, carbonate, mixed siliciclastic–carbonate, and volcaniclastic facies. These facies form associations indicative of alluvial fan, floodplain, and shallow-water lacustrine settings. Alluvial fan deposits are dominated by conglomerates and sandstones forming braided systems. Fluviolacustrine successions show a transition from clay-rich siltstones with calcareous nodules to nodular and massive limestones, marking a gradual shift from fluvial to lacustrine conditions. Laminated limestones and stromatolites indicate intermittent microbial activity that contributed to carbonate precipitation. Sedimentation was strongly influenced by volcanic inputs and climatic fluctuations, alternating between humid and arid conditions. These factors drove cycles of channel incision, sediment infill, and lake expansion–contraction, illustrating the dynamic interplay of volcanism and climate that modulated deposition in these Ediacaran continental basins, with broad relevance to our understanding of this critical window in the Earth’s history. Full article

(This article belongs to the Section Sedimentology, Stratigraphy and Palaeontology)

► Show Figures

Figure 1

35 pages, 21669 KB

Open AccessArticle

Integrated Sentinel-2 and UAV Remote Sensing for Rare-Metal Pegmatite–Greisen Exploration: Evidence from the Central Kalba–Narym Belt, East Kazakhstan

by Marzhan Rakhymberdina, Roman Shults, Baitak Apshikur, Yerkebulan Bekishev, Yevgeniy Grokhotov, Azamat Kapasov and Damir Mukyshev

Geosciences 2026, 16(3), 130; https://doi.org/10.3390/geosciences16030130 - 21 Mar 2026

Viewed by 290

Abstract

Rare-metal pegmatite–greisen systems are commonly small, structurally controlled, and difficult to delineate using conventional mapping alone. This study proposes a multiscale remote-sensing workflow for prospecting Li–Nb–Ta–Cs mineralisation in the Kalba–Narym rare-metal belt (East Kazakhstan) by integrating Sentinel-2 multispectral imagery, UAV-derived centimeter-scale orthomosaics, structural [...] Read more.

Rare-metal pegmatite–greisen systems are commonly small, structurally controlled, and difficult to delineate using conventional mapping alone. This study proposes a multiscale remote-sensing workflow for prospecting Li–Nb–Ta–Cs mineralisation in the Kalba–Narym rare-metal belt (East Kazakhstan) by integrating Sentinel-2 multispectral imagery, UAV-derived centimeter-scale orthomosaics, structural (lineament) analysis, and field-based mineralogical–geochemical validation. Sentinel-2 responses were first calibrated using known occurrences to derive alteration proxies related to greisenisation, silicification, Na-metasomatism, and oxidation. These proxies were combined into an Integrated Hydrothermal Alteration Index (IHAI) to highlight areas where multiple alteration processes overlap. Lineament mapping from Sentinel-2 and DEM products indicates dominant NW–SE and NE–SW structural trends, zones of elevated lineament density and intersection systematically coincide with high IHAI values. UAV orthomosaics refine satellite-scale anomalies by resolving quartz-vein networks, fracture corridors, and surface-alteration textures that are not detectable at 10–20 m resolution. Mineralogical and geochemical data confirm that high-IHAI targets correspond to albitised pegmatites and greisenised rocks enriched in Li, Nb, Ta, and Cs. The results demonstrate that combining freely available Sentinel-2 data with UAV observations and targeted ground validation provides a cost-effective and transferable framework for reducing false positives and prioritising exploration targets in structurally complex granitoid terranes. Full article

► Show Figures

Figure 1

24 pages, 6108 KB

Open AccessArticle

Comparative Statistical Detection of Ionospheric GPS-TEC Anomalies Associated with the 2021 Haiti and 2022 Cyprus Earthquakes

by Sanjoy Kumar Pal, Kousik Nanda, Soumen Sarkar, Stelios M. Potirakis, Masashi Hayakawa and Sudipta Sasmal

Geosciences 2026, 16(3), 129; https://doi.org/10.3390/geosciences16030129 - 20 Mar 2026

Viewed by 288

Abstract

Global Positioning System (GPS)-derived ionospheric electron concentration measurements provide a powerful observational framework for seismo-electromagnetic studies, enabling quantitative investigation of lithosphere–atmosphere–ionosphere coupling processes through statistically detectable perturbations in ionospheric electron concentration. We analyze GPS-derived Vertical Total Electron Content (VTEC) variations associated with the [...] Read more.

Global Positioning System (GPS)-derived ionospheric electron concentration measurements provide a powerful observational framework for seismo-electromagnetic studies, enabling quantitative investigation of lithosphere–atmosphere–ionosphere coupling processes through statistically detectable perturbations in ionospheric electron concentration. We analyze GPS-derived Vertical Total Electron Content (VTEC) variations associated with the 14 August 2021 Haiti earthquake (

M_{w}

7.2) and the 11 January 2022 Cyprus earthquake (

M_{w}

6.6) using data from nearby International GNSS (Global Navigation Satellite System) Service (IGS) stations located within their respective earthquake preparation zones. VTEC time series spanning 45 days before and 7 days after each event are processed to remove the diurnal component, yielding residuals that isolate short-term ionospheric variability. Anomaly detection is performed using three statistical frameworks: a Gaussian mean, standard deviation model, a robust median/median absolute deviation (MAD) model, and a distribution-free quantile-based model. Daily “occurrence” and “energy” indices are constructed to quantify the frequency and cumulative strength of detected anomalies, respectively. While the indices exhibit similar temporal patterns across all methods, they indicate frequent anomaly detection, limiting statistical selectivity. To address this, both indices are normalized by their median values and filtered using a 95% quantile threshold, retaining only extreme deviations. This procedure substantially reduces background fluctuations and isolates a small number of statistically significant anomaly peaks. For both earthquakes, enhanced anomaly activity is identified in the weeks preceding the events, whereas post-event peaks coincide with periods of elevated meteorological and geomagnetic activity. The results demonstrate that normalization combined with robust statistical methods is essential for discriminating significant ionospheric TEC anomalies from background variability. Full article

(This article belongs to the Section Natural Hazards)

► Show Figures

Figure 1

20 pages, 2893 KB

Open AccessArticle

Two-Phase Pockmark Modeling and Gas Saturation Estimation Beneath Hydrate-Bearing Sediments: Insights from the Storegga Slide

by Zheng Su, Yifan Wu, Chao Yang and Nengyou Wu

Geosciences 2026, 16(3), 128; https://doi.org/10.3390/geosciences16030128 - 20 Mar 2026

Viewed by 183

Abstract

Fluid seepages and seabed pockmarks are widely observed on continental margins worldwide in hydrate- and non-hydrate-bearing sediment. Subsurface gas chimneys connecting seafloor pockmarks to underlying gas reservoirs are commonly revealed by seismic reflection data, indicating pathways of past and present fluid migration. Fluid [...] Read more.

Fluid seepages and seabed pockmarks are widely observed on continental margins worldwide in hydrate- and non-hydrate-bearing sediment. Subsurface gas chimneys connecting seafloor pockmarks to underlying gas reservoirs are commonly revealed by seismic reflection data, indicating pathways of past and present fluid migration. Fluid seepage occurs when the seal of a gas reservoir is breached, allowing fluids to migrate upward and vent at the seafloor, forming pockmarks. In hydrate-bearing settings, gas reservoirs beneath hydrate layers typically consist of coexisting water and gas phases. However, quantitative constraints on gas saturation in free-gas zones beneath hydrates inferred from pockmark morphology remain limited. In this study, a two-phase pockmark model was developed to investigate gas-chimney growth and pockmark formation, and to estimate gas saturation in free-gas zones below hydrates using pockmark depth and gas-zone thickness as key parameters. The model was applied to the Storegga Slide region off Norway, where hydrates, pockmarks, and chimney-like seismic anomalies have been documented. Here, the application is intended to represent localized near-threshold (pre-seepage) conditions leading to pockmark initiation, rather than the present-day post-venting state. Model results for the initiation (near-threshold, pre-venting) stage indicate that the effective gas saturation in the free-gas reservoir beneath the hydrates was approximately 1.36–1.58% for gas-zone thicknesses of 50–100 m, and that the corresponding chimney-propagation timescale during initiation was on the order of ~200 years. These estimates represent threshold conditions required for seal breach and pockmark formation rather than present-day seepage states. During venting, methane gas may form hydrates within the chimney inside the hydrate stability zone, while authigenic carbonates precipitate in pockmarks and shallow sediments. These secondary hydrates and carbonates eventually seal the chimney, leaving behind a residual gas chimney in the subsurface sediment. Full article

(This article belongs to the Section Geophysics)

► Show Figures

Figure 1

30 pages, 38366 KB

Open AccessArticle

Mineralogy of Fossil Wood from the Miocene Goderdzi Formation, Republic of Georgia

by Miriani Makadze and George E. Mustoe

Geosciences 2026, 16(3), 127; https://doi.org/10.3390/geosciences16030127 - 18 Mar 2026

Viewed by 325

Abstract

The widespread abundance of silicified wood and fossil leaves in southwestern Georgia is associated with the upper Miocene-lower Pliocene volcanic deposits of the Goderdzi Formation. Neogene volcanic terrains frequently preserve exceptionally detailed fossil records, providing valuable insights into ancient environments, climate regimes, and [...] Read more.

The widespread abundance of silicified wood and fossil leaves in southwestern Georgia is associated with the upper Miocene-lower Pliocene volcanic deposits of the Goderdzi Formation. Neogene volcanic terrains frequently preserve exceptionally detailed fossil records, providing valuable insights into ancient environments, climate regimes, and vegetational dynamics. Extensive upper Miocene volcanic activity produced thick pyroclastic deposits, lahar flows, and localized sedimentary basins that facilitated the rapid burial and preservation of diverse plant remains, including silicified wood and well-preserved fossil leaves. The mineralogy of Goderdzi Formation fossil woods is surprisingly complex, with compositions that include opal-A, opal-Ct, chalcedony, and microcrystalline quartz. These minerals are evidence of variations in hydrothermal fluid circulation that led to episodes of mineral precipitation that typically occurred in several discrete steps. Full article

(This article belongs to the Section Sedimentology, Stratigraphy and Palaeontology)

► Show Figures

Figure 1

15 pages, 3251 KB

Open AccessArticle

Subsurface Temperature Assessment: Improving Reliability of Deep Well Data

by Iva Kolenković Močilac, Marko Cvetković, Zrinka Stojanović and Anđela Papić

Geosciences 2026, 16(3), 126; https://doi.org/10.3390/geosciences16030126 - 18 Mar 2026

Viewed by 257

Abstract

Reliable subsurface temperature estimates are crucial for most geoenergy projects, as they directly influence the properties of both rocks and fluids. They are particularly important in geothermal energy exploration, where errors in estimating the static formation temperature (SFT) can lead to significant misinterpretations, [...] Read more.

Reliable subsurface temperature estimates are crucial for most geoenergy projects, as they directly influence the properties of both rocks and fluids. They are particularly important in geothermal energy exploration, where errors in estimating the static formation temperature (SFT) can lead to significant misinterpretations, potentially resulting in incorrect classification of the geothermal resource. Various corrections are applied to bottom-hole temperatures (BHTs), with the Horner correction being the most widely used. In addition, empirical methods have been developed to improve accuracy at the local scale. In this study, maximum temperature values (Tmax) reported for deep exploration wells in the Sava and Drava Basins were compared to both Horner-corrected temperatures (HPCTs) and those recorded during drill-stem tests (TDST). In both basins, Tmax values frequently significantly diverge from HPCT measurements, emphasizing the limited reliability of Tmax for estimating subsurface temperatures. In the Sava Basin, 61% of wells show Tmax-HPCT differences greater than 10 °C, and in seven wells the discrepancy exceeds 20 °C. Similarly, in the Drava Basin, nearly half of the wells exhibit differences greater than 10 °C, with five wells showing deviations above 20 °C. In most cases, the reported Tmax values do not represent true maxima, so the linear regression was performed between Tmax and temperatures obtained from DST measurements, providing a basis for refining subsurface temperature estimates. Full article

(This article belongs to the Special Issue Advancements in Geological Fluid Flow and Mechanical Properties)

► Show Figures

Figure 1

27 pages, 10326 KB

Open AccessArticle

Acid-Generating and Acid-Neutralizing Reactions in the Pyrite-Rich Waste Rock Composing the Main Waste Stockpile at the Red Dog Mine, Alaska, USA

by Jeff B. Langman, Amanda Balogh, D. Eric Aston, Timothy E. Link, Emile Milan, Bridget Eckhardt and Sarah Mulzet

Geosciences 2026, 16(3), 125; https://doi.org/10.3390/geosciences16030125 - 17 Mar 2026

Viewed by 358

Abstract

Mining at the Red Dog Mine generated a 60 million-tonne waste rock stockpile that produces acid rock drainage with pH values typically below 3. The drainage chemistry is controlled by the competing kinetics of acid-generating iron sulfide weathering and acid-neutralizing carbonate and phosphate [...] Read more.

Mining at the Red Dog Mine generated a 60 million-tonne waste rock stockpile that produces acid rock drainage with pH values typically below 3. The drainage chemistry is controlled by the competing kinetics of acid-generating iron sulfide weathering and acid-neutralizing carbonate and phosphate dissolution. To evaluate the interaction of these reactions, waste rock was collected from the stockpile by drilling a borehole from the surface to a depth of 52 m, terminating at the shale bedrock. A temporal paste pH test was conducted to extend the utility of the static paste pH test to a continuous (30 min) measurement of pH and ORP over a 24-h period. The 24-h paste pH results revealed multiple acid-generating and acid-neutralizing reactions: pH values ranged from 3.31 to 6.96. Mineralogical analysis indicated initial acidic conditions in 12 of the depth intervals (upper and lower zones) were due to the release of stored acidity from soluble iron sulfate minerals. Subsequent pH increases were driven by calcite dissolution and likely phosphate and clay mineral acid-neutralizing reactions. Conversely, late-stage pH decreases in the lower middle zone indicated the presence of highly reactive/available iron sulfide surfaces, which allowed for earlier acid generation compared to less reactive/available iron sulfide minerals in other zones. The utility of this temporal paste pH test and associated mineral analysis is to understand the mineralogical controls on early temporal acid generation to guide batch reactor testing of remaining acid potential under saturated conditions. This sequential approach provides critical information for predicting long-term acid generation and information management of the stockpile for mine site remediation and closure. Full article

(This article belongs to the Topic Environmental Pollution and Remediation in Mining Areas)

► Show Figures

Figure 1

15 pages, 3784 KB

Open AccessArticle

Foraminifera and Calcareous Nannofossils in Archaeological Ceramics of Eastern Sicily: Survivors or Archaeometric Tool?

by Angela Baldanza, Maurizio Triscari, Marcella Di Bella and Giuseppe Sabatino

Geosciences 2026, 16(3), 124; https://doi.org/10.3390/geosciences16030124 - 16 Mar 2026

Viewed by 252

Abstract

The identification of calcareous foraminifera and nannofossils in archaeological ceramics (tiles and bricks from the Archaic to Roman ages) of Naxos and Taormina (Sicily) has, along with other evidence and archaeometric analyses, addressed aspects of technology and raw material source areas. Microfossils, like [...] Read more.

The identification of calcareous foraminifera and nannofossils in archaeological ceramics (tiles and bricks from the Archaic to Roman ages) of Naxos and Taormina (Sicily) has, along with other evidence and archaeometric analyses, addressed aspects of technology and raw material source areas. Microfossils, like the other aplastic inclusions, help to interpret ceramic pastes. This paper provides, for northeastern Sicily, a contribution demonstrating the importance of an integrated approach in the study of archaeological ceramics; micropaleontological analysis supports mineralogical, petrographic and chemical data to constrain interpretations of provenance and technology. The preservation of foraminifera calcitic tests and coccoliths is an additional key to identifying errors, failures and strategies during the ancient ceramic firing process. Comparisons with the micropaleontological content of locally outcropping clay deposits have allowed for the unambiguous identification of the clay sources used for ancient ceramic production in the region. Full article

(This article belongs to the Section Biogeosciences)

► Show Figures

Figure 1

16 pages, 5617 KB

Open AccessArticle

Sequence Stratigraphic, Resource Potential, and Global Cretaceous Event Linkage of the Shahezi Formation in the Xujiaweizi Fault Depression: New Insights from Well SK2

by Yangyang Zhao, Hesheng Hou, Dongzhao An, Wei Fu, Jiaodong Zhang, Youfeng Gao and Feng Ma

Geosciences 2026, 16(3), 123; https://doi.org/10.3390/geosciences16030123 - 16 Mar 2026

Viewed by 325

Abstract

The Xujiaweizi Fault Depression in the Songliao Basin is a significant area for deep natural gas exploration, and the Shahezi Formation has been recognized as the primary hydrocarbon-source rock. This research integrates core, logging, and seismic data from Well SK2, the world’s first [...] Read more.

The Xujiaweizi Fault Depression in the Songliao Basin is a significant area for deep natural gas exploration, and the Shahezi Formation has been recognized as the primary hydrocarbon-source rock. This research integrates core, logging, and seismic data from Well SK2, the world’s first scientific drilling well to reach a depth of 7018 m and obtain 2624 m of continuous cores from the Shahezi Formation. The study aims to redefine the stratigraphic framework, resource characteristics, and sedimentary evolution of the formation in the Cretaceous period. The Shahezi Formation, dating from 118 to 112 Ma (mid-Aptian to early Albian), is divided into five third-order sequences (SQ1–SQ5). The upper section of SQ5 and SQ2 shows the highest potential for deep gas, featuring high-maturity Type III kerogen, 35 gas anomaly layers with a total thickness of 79 m, and a 59% proportion of dark mudstone. A three-stage sedimentary evolution model, including initial faulting, intense faulting, and contraction, is proposed, establishing a link between terrestrial sedimentation and global Early Cretaceous events (e.g., OAE1b). This research provides crucial insights for deep gas exploration and global marine–terrestrial sedimentary comparisons. Full article

► Show Figures

Figure 1

29 pages, 47085 KB

Open AccessArticle

Discovery of Waimirite-(Y) in Egypt: Insights into REE Mineralization in Neoproterozoic Granite and Metasediments, Wadi Abu Rusheid, Eastern Desert

by Mustafa A. Elsagheer, Hilmy E. Moussa, Ayman E. Maurice, Paul D. Asimow, Oliver D. Wilner, Maysa M. N. Taha, Adel A. Surour and Mokhles K. Azer

Geosciences 2026, 16(3), 122; https://doi.org/10.3390/geosciences16030122 - 16 Mar 2026

Viewed by 301

Abstract

We report, for the first time, waimirite-(Y) in Egypt. This is only the third reported occurrence of this mineral in the world. This observation arose during our study of the rare earth element (REE) mineralization associated with the Neoproterozoic rare-metal granite intrusion in [...] Read more.

We report, for the first time, waimirite-(Y) in Egypt. This is only the third reported occurrence of this mineral in the world. This observation arose during our study of the rare earth element (REE) mineralization associated with the Neoproterozoic rare-metal granite intrusion in Wadi Abu Rusheid in the Eastern Desert of Egypt. The principal lanthanide and yttrium (Y) hosts in the area are waimirite-(Y) and bastnäsite-(Ce) in leucogranite and bastnäsite-(Y) in adjacent metasedimentary country rock. The leucogranite is a strongly fractionated, metaluminous to weakly peraluminous (A/CNK = 0.98–1.03), medium- to high-K calk-alkaline I-type granite. The metasediments are composed of upper greenschist to lower amphibolite-grade biotite schists with variable amounts of amphibole, graphite, and garnet. Leucogranite contains accessory Li-bearing mica, garnet, zircon, fluorite, and columbite in addition to the REE minerals. It is enriched by three orders of magnitude relative to primitive mantle in Li, Rb, Th, Ta, Nb, Pb, U, and Sn; relative to these highly enriched elements the concentrations of Sr, Ba, Ga, Zr, Hf, and Y are notably low. The REE patterns of most samples show strong enrichment in heavy relative to light REE but occasional samples have light REE-enriched patterns controlled by accessory REE minerals, and all display strong negative Eu anomalies (Eu/Eu* ≤ 0.05). The whole-rock chemistry of the metasedimentary units are different; relative to average upper continental crust they show enrichments of one to two orders of magnitude in Li, Rb, Pb, Sn, Cs, and sometimes Cr and Zn. The REE patterns of the metasedimentary units are nearly flat, with some samples showing negative Eu anomalies. Waimirite-(Y), nominally YF₃, also contains several weight percent each of Yb, Dy, and Er. The empirical formula (based on one cation) is (Y_0.55Ce_0.02Pr_0.01Nd_0.02Sm_0.02Gd_0.02Dy_0.05Er_0.04Yb_0.05Th_0.05Ca_0.16Pb_0.01)_∑1.00(F_2.48O_0.52)_∑3.00. Bastnäsite-(Ce) in leucogranite samples, nominally Ce(CO₃)F, also has several weight percent each of Nd₂O₃ and La₂O₃. The REE host in metasedimentary rocks is bastnäsite-(Y), nominally Y(CO₃)F, but also rich in Nd₂O₃ (11–19 wt.%) and La₂O₃ (4–14 wt.%). It is intimately associated with fluorophlogopite. The geochemical, mineralogical, and textural evidence indicates that waimirite-(Y) and bastnäsite-(Ce) in leucogranite crystallized from granite-derived F- and CO₂-bearing hydrothermal fluids, whereas the source of Y for growth of the bastnäsite-(Y) in the metasedimentary rocks is unclear; the large negative Ce anomaly in bastnäsite-(Y) suggests an oxidizing supergene setting. Despite their proximity, if there is a genetic connection between the mineralization in the granite and in its country rocks, the relationship is not evident from elemental patterns or host mineralogy. Full article

(This article belongs to the Section Geochemistry)

► Show Figures

Figure 1

20 pages, 6922 KB

Open AccessArticle

Surface Deformation Monitoring and Analysis of the Bayan Obo Rare Earth Mining Area Using Dual-Ascending SBAS-InSAR Data Fusion

by Yanliu Ding, Xixi Liu, Jing Tian, Shiyong Yan, Lixin Lin and Han Ma

Geosciences 2026, 16(3), 121; https://doi.org/10.3390/geosciences16030121 - 16 Mar 2026

Viewed by 288

Abstract

The Bayan Obo Mining District, recognized as the largest rare-earth resource base worldwide, has experienced significant surface instability due to intensive mining and large-scale dumping activities. To address the challenges posed by complex geological conditions and mining-induced disturbances, this study employs dual-ascending Sentinel-1A [...] Read more.

The Bayan Obo Mining District, recognized as the largest rare-earth resource base worldwide, has experienced significant surface instability due to intensive mining and large-scale dumping activities. To address the challenges posed by complex geological conditions and mining-induced disturbances, this study employs dual-ascending Sentinel-1A C-band Synthetic Aperture Radar (SAR) datasets (Path 11 and Path 113) and applies the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to retrieve time-series deformation along the line-of-sight (LOS) direction for each track. Through temporal normalization and spatial matching, paired LOS observations from the two tracks were established. Based on the SAR observation geometry and under the assumption that the north–south component is negligible, a LOS projection model was constructed and a geometric decomposition was performed to derive the east–west and vertical two-dimensional deformation fields. The results indicate that the study area is generally stable, while significant subsidence occurs in the northern pit and adjacent waste-dump zones, with local maximum rates approaching 50 mm/year, predominantly controlled by the vertical component. The two-dimensional deformation analysis reveals that vertical displacement dominates surface motion, whereas east–west movement shows smaller amplitudes but clear directional concentration. In particular, the east–west slopes exhibit slightly higher velocities, suggesting a lateral adjustment tendency along this direction, likely related to the overall east–west geometric configuration of the open-pit and waste-dump areas. Time-series observations further reveal that precipitation-related surface deformation occurs with an approximate two-month delay, reflecting the hydrological–mechanical coupling processes of rainfall infiltration, pore-water pressure propagation, and dump-material consolidation. Overall, this study reveals the multi-dimensional deformation characteristics and precipitation-driven stage-wise response of the mining area, demonstrating the effectiveness of the dual-ascending SBAS-InSAR for two-dimensional deformation monitoring in highly disturbed environments, and providing a scientific basis for surface stability assessment and geohazard prevention. Full article

► Show Figures

Figure 1

19 pages, 6662 KB

Open AccessArticle

Natural H₂ Emanations in the Rio de la Plata Craton, First Data

by Isabelle Moretti, Alain Prinzhofer and Vincent Roche

Geosciences 2026, 16(3), 120; https://doi.org/10.3390/geosciences16030120 - 14 Mar 2026

Viewed by 446

Abstract

This study presents the first comprehensive soil gas survey across southern Uruguay’s H₂ prospective terranes. A pre-field trip selection was done on the basement rock nature, as well as vegetation anomalies in subcircular depressions and fault presence. The Neoproterozoic terrane, north of [...] Read more.

This study presents the first comprehensive soil gas survey across southern Uruguay’s H₂ prospective terranes. A pre-field trip selection was done on the basement rock nature, as well as vegetation anomalies in subcircular depressions and fault presence. The Neoproterozoic terrane, north of Punta del Este, and the Archean Rio de la Plata Craton, north of Montevideo, as well as along the suture zones between the two, were targeted. Our findings reveal substantial H₂ concentrations, significantly outperforming many established basins worldwide. The suture zones act as critical migration conduits for H₂ coming from a deeper structural level. Slightly abnormal helium signatures confirm an active, deep-sourced fluid system, particularly within the Sierra Ballena and Cordillera shear zones. The Archean Rio de la Plata Craton appears promising but has only been partially sampled and warrants further investigation. These results underscore the high potential of Uruguay as a new frontier for natural hydrogen exploration. Full article

► Show Figures

Figure 1

31 pages, 6428 KB

Open AccessArticle

Investigation of Plate Movements on the Antarctic Continent and Its Surroundings Using GNSS Data and Global Plate Models

by Abdullah Kellevezir, Ekrem Tuşat and Mustafa Tevfik Özlüdemir

Geosciences 2026, 16(3), 119; https://doi.org/10.3390/geosciences16030119 - 13 Mar 2026

Viewed by 465

Abstract

The Earth’s lithosphere, the rigid outermost layer of the planet, is composed of numerous tectonic plates of varying sizes that move over the underlying asthenosphere. The motion and interaction of these plates give rise to a wide range of geodynamic processes. Accurate monitoring [...] Read more.

The Earth’s lithosphere, the rigid outermost layer of the planet, is composed of numerous tectonic plates of varying sizes that move over the underlying asthenosphere. The motion and interaction of these plates give rise to a wide range of geodynamic processes. Accurate monitoring of these processes is essential for maintaining a stable, up-to-date, and reliable terrestrial reference frame. This study investigates the horizontal and vertical motions of the Antarctic Plate resulting from its interactions with adjacent plates. Tectonic plate movements can be determined using several space-geodetic techniques, including Global Navigation Satellite Systems (GNSS), Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and Interferometric Synthetic Aperture Radar (InSAR). Among these methods, GNSS is currently the most widely used, as plate motions can be derived from continuous observations recorded at permanent stations and processed using scientific or commercial software. Within the scope of this research, GNSS data collected between 2020 and 2023 were processed using the GAMIT/GLOBK V.10.7 software package to estimate the coordinates and velocities of stations located on the Antarctic, South American, African, and Australian Plates in the ITRF14 reference frame. Furthermore, plate-fixed solutions were generated to analyze the relative motion of the Antarctic Plate with respect to neighboring plates. The results indicate that the Antarctic Plate moves at an average velocity of approximately 4–18 mm/year in the ITRF14 frame. The plate diverges from both the African and Australian Plates and exhibits predominantly strike-slip motion relative to the South American Plate. A comparison with existing global plate motion models demonstrates that the obtained velocities are consistent within 0–5 mm/year. Full article

(This article belongs to the Section Geophysics)

► Show Figures

Figure 1

25 pages, 5458 KB

Open AccessArticle

Neural Network Inversion Algorithm for Geostress Field Based on Physics-Informed Constraints

by Fei Li, Lin Wang, Zhifeng Liang, Jinan Wang, Chuanqi Zhu and Ruiyang Yuan

Geosciences 2026, 16(3), 118; https://doi.org/10.3390/geosciences16030118 - 12 Mar 2026

Viewed by 342

Abstract

Traditional methods for geostressfield inversion face issues such as weak physical interpretability and insufficient generalization ability. This study pioneers the application of Physics-Informed Neural Network (PINN) to this problem, developing a data- and physics-driven inversion algorithm. The framework incorporates a constitutive-equation-based regularized loss [...] Read more.

Traditional methods for geostressfield inversion face issues such as weak physical interpretability and insufficient generalization ability. This study pioneers the application of Physics-Informed Neural Network (PINN) to this problem, developing a data- and physics-driven inversion algorithm. The framework incorporates a constitutive-equation-based regularized loss function as a hard constraint during training to ensure physical consistency. To address boundary load uncertainty, two quantification approaches—Bayesian linear regression and surrogate model optimization—are proposed to establish 95% confidence intervals for boundary coefficients. Verification based on simple three-dimensional models and actual geological models of mines shows that PINN inversion achieves a mean absolute relative error as low as 0.0772%, with an error of 15.67% under sparse sampling conditions—significantly lower than the 31.07% error of the traditional Back propagation neural network. This demonstrates excellent robustness and data efficiency. In the practical engineering application of complex geological bodies, the average error of principal stress inversion is 9.35% with a minimum error of 0.137%. All inversion results fall within the permissible accuracy range of engineering, and the stress distribution conforms to basic laws, with an average error of 0.453 in the constitutive relation. Compared with BP neural network and multiple linear regression methods, it shows obvious accuracy advantages. This method provides a new solution for intelligent ground stress prediction with high accuracy, high efficiency, and strong physical interpretability, and also lays the foundation for early identification of geological disasters. Full article

(This article belongs to the Special Issue New Trends in Numerical Methods in Rock Mechanics)

► Show Figures

Figure 1

18 pages, 2468 KB

Open AccessArticle

Pyrolysis Kinetics of Kerogen and Bitumen in Shahejie Shale: Implications for In Situ Heating Strategies

by Chenge Zheng, Yiwei Wang, Xiaowei Huang, Weijiao Ma, Jinzhong Liu, Qiang Wang, Cui Weng and Yong Li

Geosciences 2026, 16(3), 117; https://doi.org/10.3390/geosciences16030117 - 12 Mar 2026

Viewed by 363

Abstract

Unconventional shale resources remain crucial to energy security. In situ conversion technology (ICP) offers a promising pathway for exploiting low–maturity shale, yet the distinct roles of kerogen and bitumen during thermal conversion are not fully understood. This study investigates the decomposition behavior of [...] Read more.

Unconventional shale resources remain crucial to energy security. In situ conversion technology (ICP) offers a promising pathway for exploiting low–maturity shale, yet the distinct roles of kerogen and bitumen during thermal conversion are not fully understood. This study investigates the decomposition behavior of kerogen and extracted bitumen from the Shahejie Formation through gold–tube pyrolysis experiments at 50 MPa and heating rates of 2 °C/h and 20 °C/h. The results show that the yield curves of C₁, C₂–C₅, and C₆–C₁₄ generated from kerogen and bitumen exhibited similar trends. In contrast to the C₁₅₊ fraction from kerogen, which initially increased and then decreased, the yield of C₁₅₊ from bitumen began to decline from the onset of cracking. Additionally, the CO₂ generated from the kerogen continued to increase until the end of pyrolysis, whereas the CO₂ from the bitumen reached its maximum at an EasyRo of approximately 1.8%. The kinetic results show that bitumen has a higher activation energy for gas generation than kerogen, while kerogen has a higher activation energy for oil generation than bitumen. A heating program of 1 °C/day rate, 324 d duration, and a final temperature of 360 °C was applied to predict oil and gas generation during ICP. Below 326 °C, the proportion of C₁ and C₂–C₅ contributed by kerogen increased and exceeded 90%. Although kerogen’s contribution ratio of C₆–C₁₄ exhibited fluctuating variation characteristics, it remained above 50% across most of the intervals. The gas–to–oil ratio increased rapidly above 299 °C and reached 375 m³/m³ by the end of heating. Full article

(This article belongs to the Special Issue Advances in Oil and Gas Exploration, Resources, and Production in China)

► Show Figures

Figure 1

4 pages, 145 KB

Open AccessEditorial

Editorial of Board Members’ Collection Series: “New Horizons in Geophysics: From Theory to Applications”

by Luciano Telesca, Lev V. Eppelbaum and Georgios Balasis

Geosciences 2026, 16(3), 116; https://doi.org/10.3390/geosciences16030116 - 12 Mar 2026

Viewed by 264

Abstract

Geophysics represents a dynamic research field that delves into the intricate physical properties and processes that shape the Earth and its surrounding space environment [...] Full article

(This article belongs to the Special Issue Editorial Board Members’ Collection Series: “New Horizons in Geophysics: From Theory to Applications”)

1 pages, 126 KB

Open AccessCorrection

Correction: Fuławka et al. Frequency-Dependent Slope Stability Under Earthquake Loading: A Parametric Study with Hybrid FEM–LEM. Geosciences 2025, 15, 460

by Krzysztof Fuławka, Bogumiła Pałac-Walko and Lech Stolecki

Geosciences 2026, 16(3), 115; https://doi.org/10.3390/geosciences16030115 - 12 Mar 2026

Viewed by 157

Abstract

There was an error in the original publication [...] Full article

(This article belongs to the Topic From Earth to Innovation: Modern Trends in Mining, Geoinformation, and Geoscientific Applications)

28 pages, 10613 KB

Open AccessArticle

Characterization of Hydrogeologic and Lithologic Heterogeneity Along the Southern Shore of the Great Salt Lake, Utah, from Electrical Methods

by Mason Jacketta, Michael S. Thorne, Surya Pachhai, Ivan Tochimani-Hernandez, Tonie van Dam, Christian L. Hardwick, Ebenezer Adomako-Mensah, William P. Johnson and Leif S. Anderson

Geosciences 2026, 16(3), 114; https://doi.org/10.3390/geosciences16030114 - 11 Mar 2026

Cited by 1 | Viewed by 524

Abstract

Water levels in the Great Salt Lake (GSL), UT, USA, have been declining overall since 1989, leading to a 70% decrease in surface area. To understand GSL’s future, we seek to image fresh groundwater input and lithologic variation along the lake’s boundary. Determining [...] Read more.

Water levels in the Great Salt Lake (GSL), UT, USA, have been declining overall since 1989, leading to a 70% decrease in surface area. To understand GSL’s future, we seek to image fresh groundwater input and lithologic variation along the lake’s boundary. Determining the amount of groundwater recharge into GSL is crucial for lake management but currently unknown. During the Fall of 2024 and Spring 2025, we conducted 16 electrical resistivity tomography (ERT) and six transient electromagnetic (TEM) surveys along the southern shore of GSL between Burmester Road (to the West), Saltair, and Lee’s Creek (to the East). These measurements indicate a low-resistivity layer consistent with brine pore-water, with variable thickness ranging from 7.1 ± 0.1 m at Burmester to 9.6 ± 0.2 m at Saltair. The Saltair region shows a high-resistivity layer, consistent with a 4.4 ± 0.05 m thick layer of mirabilite. This layer contains vertical conduits that allow saline pore-water to upwell onto the surface forming evaporite deposits. Near Lee’s Creek, we find evidence of high resistivities consistent with fresher groundwater as shallow as 2.8 ± 0.03 m, where increased permeability along the paleo-Jordan River corridor may provide a path for groundwater recharge from the Wasatch Mountains. Full article

(This article belongs to the Section Hydrogeology)

► Show Figures

Figure 1

16 pages, 11029 KB

Open AccessArticle

Late Miocene Warming in the Tropics Based on Planktonic Foraminiferal Assemblages

by Marfasran Hendrizan, Mutiara Rachmat Putri, Fareza Sasongko Yuwono, Rubiyanto Kapid, Winda Eka Mandiri Puteri, Anisa Ulfatu Hasanah, Lia Jurnaliah, Praptisih Praptisih and Harisma Harisma

Geosciences 2026, 16(3), 113; https://doi.org/10.3390/geosciences16030113 - 9 Mar 2026

Viewed by 1794

Abstract

The Late Miocene is known as a period of long-term Cenozoic global cooling and decreasing concentrations of atmospheric CO₂. The conditions provide the opportunity to assess the Earth’s climate sensitivity in altering internal and external drivers in a warmer world with [...] Read more.

The Late Miocene is known as a period of long-term Cenozoic global cooling and decreasing concentrations of atmospheric CO₂. The conditions provide the opportunity to assess the Earth’s climate sensitivity in altering internal and external drivers in a warmer world with similarity to the modern continental configuration. However, relative warmer Sea Surface Temperature (SST), a deepened thermocline, and reduced upwelling may have occurred in the tropics during the Late Miocene global cooling. Here, we present foraminiferal biostratigraphy data from the Middle Miocene–Pliocene succession in the Halang Formation in the Banyumas Basin in Indonesia. An increase in the planktonic foraminifera Trilobatus trilobus and Orbulina universa during the Late Miocene in the Indian Ocean indicates relative surface temperature warming and reduced productivity inferred from assemblage shifts. Reduced productivity was caused by decreasing upwelling intensity during the Late Miocene based on Globigerinella obesa assemblages. Reduced upwelling in the south of Java is supported by elevated numbers of surface/mixed-layer species (i.e., Trilobatus sacculifer and Trilobatus immaturus). We suppose the distribution of enhanced upper-layer stratification in the eastern Indian Ocean was not only driven by oceanic forcing but was also transferred intensively into the Indian Ocean by atmospheric forcing of strengthening equatorial trade winds. Changes in the Walker circulation controlled a reduction in upwelling over the eastern tropical Indian Ocean and a deeper thermocline during the cooling climate in the Late Miocene. Full article

(This article belongs to the Section Sedimentology, Stratigraphy and Palaeontology)

► Show Figures

Figure 1

30 pages, 18547 KB

Open AccessArticle

Hybrid Landslide Displacement Prediction via Improved Optimization

by Yuanfa Ji, Zijun Lin, Xiyan Sun and Jing Wang

Geosciences 2026, 16(3), 112; https://doi.org/10.3390/geosciences16030112 - 9 Mar 2026

Viewed by 384

Abstract

This study proposes a hybrid landslide displacement prediction model based on multi-strategy integrated optimization to address high nonlinearity and limited accuracy. An improved SFOA with Lévy flight, dynamic exploration adjustment, and stagnation detection enhances global search and convergence. The optimized SFOA (OSFOA) is [...] Read more.

This study proposes a hybrid landslide displacement prediction model based on multi-strategy integrated optimization to address high nonlinearity and limited accuracy. An improved SFOA with Lévy flight, dynamic exploration adjustment, and stagnation detection enhances global search and convergence. The optimized SFOA (OSFOA) is employed to optimize CEEMDAN using minimum envelope entropy, reducing hyperparameter subjectivity and decomposing cumulative displacement into multi-scale components. The trend term is predicted by a Bayesian-optimized ARIMA, while periodic and stochastic terms are further decomposed by VMD and predicted using Bayesian-optimized SVR. GRA-MIC is applied to select key influencing factors and optimize model inputs. Results show that the proposed method improves accuracy and stability, reducing RMSE by about 82% and 52% compared with SSA-SVR and the baseline single decomposition model, respectively. The study further identifies monthly rainfall change and two-month reservoir level variation as the dominant driving factors for the displacement evolution, providing an effective and interpretable approach for complex landslide early warning. Full article

(This article belongs to the Section Natural Hazards)

► Show Figures

Figure 1

20 pages, 3734 KB

Open AccessArticle

UFLI-Based Uranium Anomaly Layer Delineation and 3D Orebody Reconstruction of the Daying Uranium Deposit Within the Northern Ordos Basin, China

by Yulei Tan, Jianyu Huang, Liyuan Zhang, Laijun Lu, Baopeng Chen, Tongyuan Liang and Lin Pan

Geosciences 2026, 16(3), 111; https://doi.org/10.3390/geosciences16030111 - 9 Mar 2026

Viewed by 334

Abstract

Sandstone uranium deposits exhibit stratabound mineralization and strong vertical heterogeneity in geological space, which complicates the identification of uranium anomaly layers and their integration into deposit-scale 3D models using borehole datasets. In this paper, we propose a UAPC Fourier layer identification (UFLI) method [...] Read more.

Sandstone uranium deposits exhibit stratabound mineralization and strong vertical heterogeneity in geological space, which complicates the identification of uranium anomaly layers and their integration into deposit-scale 3D models using borehole datasets. In this paper, we propose a UAPC Fourier layer identification (UFLI) method for uranium anomaly layer identification. The method is based on multi-log feature construction, random forest-based estimation of a depth continuous uranium anomaly probability curve (UAPC), and improved Fourier vertical variation analysis. We used 19 boreholes arranged on four exploration lines (ZKA-ZKD) of the Daying uranium deposit in the northern Ordos Basin (north central China), for the validation. The proposed UFLI method identified 51 uranium anomaly layers at a 5 m sampling interval, forming discrete vertical clusters within the drilled successions. The results indicate that anomalies are overwhelmingly concentrated in the Middle Jurassic Zhiluo Formation, particularly within the lower Zhiluo member, with an anomaly-bearing depth range of approximately 550–745 m. Comparison with known mineralization records shows that both industrial and ordinary mineralization intervals are captured within the anomaly layers. Then, based on inter-borehole continuity of anomaly layers, we reconstructed five uranium orebodies (orebodies 1–5) and describe their distribution characteristics. The proposed method provides a technical means for subsurface visualization and exploration targeting in sandstone uranium systems. Full article

► Show Figures

Figure 1

19 pages, 1381 KB

Open AccessArticle

Geochemical and Radiological Characterization of Granitic-Derived Highland Coffee Soils in Chiang Mai, Thailand

by Khemruthai Kheamsiri, Naofumi Akata, Chutima Kranrod, Hirofumi Tazoe, Tarika Thumvijit, Ilsa Rosianna, Haruka Kuwata, Krit Khetanun, Narit Yimyam, Yusuke Unno and Akira Takeda

Geosciences 2026, 16(3), 110; https://doi.org/10.3390/geosciences16030110 - 8 Mar 2026

Viewed by 383

Abstract

Granitic soils in the Highlands support the cultivation of Arabica coffee in northern Thailand; however, their geochemical and radiological properties are inadequately defined. This study examined major oxides, trace elements, natural radionuclides, and extractable phosphorus in granitic-derived coffee soils from the Agricultural Innovation [...] Read more.

Granitic soils in the Highlands support the cultivation of Arabica coffee in northern Thailand; however, their geochemical and radiological properties are inadequately defined. This study examined major oxides, trace elements, natural radionuclides, and extractable phosphorus in granitic-derived coffee soils from the Agricultural Innovation Research, Integration, Demonstration, and Training Center (AIRID) in Chiang Mai. Twenty soil samples were obtained from 10 locations at two depth intervals (0–30 cm and 30–60 cm). Major and trace elements were analyzed via X-ray fluorescence (XRF), natural radionuclides were analyzed through high-purity germanium (HPGe) gamma spectrometry, and extractable phosphorus was determined using the Bray II method. The soils demonstrate remarkably high ⁴⁰K activity concentrations (1.2–1.9 kBq kg⁻¹) and increased K₂O contents (4.9–7.8 wt%), about three to five times more than worldwide soil averages according to Reimann & de Caritat, indicating enrichment from potassium-rich granitic rocks. Major oxide compositions suggest extensive tropical weathering, characterized by elevated SiO₂ (>60 wt%) and Al₂O₃ (>14 wt%), alongside significant depletion of CaO and MgO (<1 wt%). In topsoil, Bray II–extractable phosphorus constitutes 10–25% of total phosphorus and has a robust positive connection with P₂O₅ (R² = 0.95, p < 0.001), signifying surface accumulation and restricted vertical mobility. Multivariate analysis indicates lithogenic grouping of trace elements with negligible vertical redistribution. These findings establish a geochemical and radiological baseline for highland coffee soils in northern Thailand, with implications for soil fertility assessment, soil–plant transfer research, and evaluations of natural radioactive exposure related to coffee production. Full article

(This article belongs to the Special Issue Soil Geochemistry)

► Show Figures

Figure 1

26 pages, 4604 KB

Open AccessArticle

Topsoil Geochemistry and Land-Use-Related Metal(loid) Risks on Maio Island, Cape Verde

by Filipa Moreno, Marina Cabral Pinto, Orquídia Neves and Rosana Neto

Geosciences 2026, 16(3), 109; https://doi.org/10.3390/geosciences16030109 - 6 Mar 2026

Viewed by 407

Abstract

Soil provides essential ecosystem services and is pivotal for achieving multiple United Nations (UN) Sustainable Development Goals amid growing population pressures and resource demands. In arid to semi-arid regions such as Maio Island (Cape Verde), nutrient-poor soils and unsustainable land-use practices increase agricultural [...] Read more.

Soil provides essential ecosystem services and is pivotal for achieving multiple United Nations (UN) Sustainable Development Goals amid growing population pressures and resource demands. In arid to semi-arid regions such as Maio Island (Cape Verde), nutrient-poor soils and unsustainable land-use practices increase agricultural vulnerability, while volcanic geochemistry introduces elements that are not human friendly, further challenging environmental quality and long-term sustainability. Assessing soil (physical–chemical–biological) condition is therefore crucial for informed environmental and land-use planning. Here, Maio’s topsoil was evaluated using protocols adapted from Santiago, the largest Cape Verdean island. Estimated Background Values (EBVs) indicated naturally elevated V, Cr, Ni, Co, and Cu concentrations, consistent with mafic volcanic terrains. Robust Principal Component Analysis (rPCA) revealed geochemical groupings linked to volcanic–sedimentary units, with the dominant component (PC1) defined by Co–V–Cu–Mn–Ni versus As–Cd. Environmental Risk Indices (ERIs) and Multi-Element ERIs (ME–ERIs) quantified elemental enrichment relative to international land-use standards (residential and agricultural) and subsequently to Maio’s EBVs. The highest exceedances were observed for Cr, Co, Ni, V, and Cu, whereas As, Cd, Hg, Pb, and Zn fell within thresholds. The EBV-based assessment identified fewer exceedances than stricter international guidelines, though a few multi-element “hotspots” persist, highlighting potential land-use constraints and the need for preventive management. Overall, the integrated EBV/ERI/ME–ERI framework establishes an environmental geochemical baseline for Maio and offers a screening tool applicable across the entire archipelago. Full article

(This article belongs to the Special Issue Geosciences, Development and Sustainability: Africa and Europe Together)

► Show Figures

Graphical abstract

20 pages, 10803 KB

Open AccessArticle

CSFM: A Novel Framework for Stratigraphic Forward Modeling of Clastic Systems

by Yuangui Zhang, Jingbin Cui, Maoshan Chen, Lei Li, Ruidong Han and Wentao Wang

Geosciences 2026, 16(3), 108; https://doi.org/10.3390/geosciences16030108 - 5 Mar 2026

Viewed by 310

Abstract

Stratigraphic forward modeling (SFM) is a numerical approach used to reconstruct sedimentary basin evolution by simulating the infilling and tectonic evolution process of strata. The challenge is that existing approaches inevitably require trade-offs among modeling fidelity and computational cost. We present a novel [...] Read more.

Stratigraphic forward modeling (SFM) is a numerical approach used to reconstruct sedimentary basin evolution by simulating the infilling and tectonic evolution process of strata. The challenge is that existing approaches inevitably require trade-offs among modeling fidelity and computational cost. We present a novel clastic stratigraphic forward modeling (CSFM) approach to reducing computational cost while retaining key flow and transport behaviors relevant to stratigraphic architecture. In CSFM, Lagrangian water particles affect momentum and sediment, while a fixed Eulerian grid stores topographic elevation and lithologic fractions. A simplified form of the Navier–Stokes equations is proposed to compute the trajectories of fluid particles, which can greatly reduce the computational cost. Sediment dynamics are represented by coupled suspended load and bedload modules. To validate CSFM, we constructed a synthetic alluvial fan model and performed stratigraphic forward modeling on it. Five lake-level cycles were imposed and results showed that cyclic sand–clay couplets and isolated channel sand bodies were formed during repeated progradation and backstepping. These results are consistent with established sedimentological knowledge, confirming the geological plausibility of CSFM. Full article

(This article belongs to the Section Sedimentology, Stratigraphy and Palaeontology)

► Show Figures

Figure 1

19 pages, 5514 KB

Open AccessArticle

Synergetic Controls of Lithofacies, Mineralogy, and Organic Matter on Sweet Spot Distribution in Shale Gas Reservoir: A Case Study from Permian Shanxi Formation, Eastern Ordos Basin

by Ke Wang, Jianwu Zhang, Yang Liu, Ziyu Yuan, Weiwei Zhao and Chao Liu

Geosciences 2026, 16(3), 107; https://doi.org/10.3390/geosciences16030107 - 5 Mar 2026

Viewed by 240

Abstract

The Ordos Basin hosts significant shale gas resources in China, yet its marine-continental transitional sedimentary setting causes intense reservoir heterogeneity that severely hinders accurate sweet spot identification in the Permian Shanxi Formation. This study aims to reveal the synergistic controls of lithofacies, mineralogy, [...] Read more.

The Ordos Basin hosts significant shale gas resources in China, yet its marine-continental transitional sedimentary setting causes intense reservoir heterogeneity that severely hinders accurate sweet spot identification in the Permian Shanxi Formation. This study aims to reveal the synergistic controls of lithofacies, mineralogy, and organic matter on shale gas sweet spot formation in the southern Yishan Slope of the eastern Ordos Basin. A multi-dimensional characterization approach was adopted, integrating drilling/logging data and systematic core analyses including X-ray diffraction (XRD), organic geochemical testing, porosity/permeability measurement, and on-site gas content desorption, to quantify reservoir heterogeneity across lithofacies, mineralogy, organic geochemistry, and petrophysical properties. The results show that three lithofacies associations are identified in the target interval: mud-wrapped sand, sand-mud interbedding, and sand-wrapped mud, among which sand-mud interbedding and mud-wrapped sand associations exhibit higher total organic carbon (TOC) contents and strong inter/intra-well heterogeneity. The organic matter in the reservoir is dominated by Type III kerogen, with TOC values ranging from 0.04% to 12.15%, and the Shan 2 Member shows significantly higher average TOC (2.55%) than the Shan 1 Member (1.36%). The reservoir is characterized by ultra-low porosity (average of 0.77%) and low permeability (average of 0.26 × 10⁻³ μm²), with mesopores and macropores contributing over 99% of the total pore volume and showing a significant positive correlation with gas content. Quartz (average of 34.86%) and clay minerals present strong vertical heterogeneity, with the Shan 2 Member being more heterogeneous than the Shan 1 Member due to differences in sedimentary environment evolution. A TOC threshold of 1.5% is determined for sweet spot identification in the study area, and shale gas sweet spots are synergistically controlled by high TOC abundance, moderate brittle mineral content, and 0.1–3 m thick sandy interbeds. This study enriches the theoretical understanding of marine-continental transitional shale reservoirs and provides a scientific basis for sweet spot prediction and development optimization in similar heterogeneous shale gas systems worldwide. Full article

(This article belongs to the Topic Recent Advances in Diagenesis and Reservoir 3D Modeling)

► Show Figures

Figure 1

18 pages, 8958 KB

Open AccessArticle

Study on Progressive Damage Characteristics of Pre-Cracked Weak Sandstone Under Uniaxial Creep

by Haotian Fu, Guodong Li, Honglin Liu, Yongqiang Wu, Hongzhi Wang and Zhiqiang Liu

Geosciences 2026, 16(3), 106; https://doi.org/10.3390/geosciences16030106 - 3 Mar 2026

Viewed by 327

Abstract

Addressing the engineering challenge of creep instability in weakly cemented fractured sandstones within extremely soft coal-bearing formations under long-term loading in western mining areas, using weakly cemented sandstone from a coal mine in Xinjiang as the study subject. This research employs uniaxial graded [...] Read more.

Addressing the engineering challenge of creep instability in weakly cemented fractured sandstones within extremely soft coal-bearing formations under long-term loading in western mining areas, using weakly cemented sandstone from a coal mine in Xinjiang as the study subject. This research employs uniaxial graded loading creep tests combined with full-information acoustic emission technology and DIC high-speed strain field observation to investigate the creep deformation patterns (The full name of “DIC” is the three-dimensional high-speed dynamic and static stress–strain analysis system of the DIC strain field measurement and analysis system. For the convenience of expression, this system will be uniformly referred to as DIC in the following text), damage evolution characteristics, and failure mechanisms of sandstone under intact, pre-fabricated 30° fractures, and pre-fabricated 60° fractures. Results indicate: Fractures significantly weaken rock strength and long-term stability. Unfractured specimens primarily exhibit columnar splitting tensile failure, while pre-fractured specimens show pronounced shear failure. Shear cracks accounted for 83.67% of failures in 30° pre-fractured specimens and decreased to 63.44% in 60° pre-fractured specimens. Intact specimens exhibited acoustic emission ringing responses during accelerated creep stages, whereas fractured specimens showed ringing responses as early as the first loading stage. During graded loading, ringing counts in pre-fractured specimens continuously accumulated, with cumulative counts significantly exceeding those of intact specimens. Pre-fabricated cracks induced significant stress concentration effects at the ends, causing failure cracks to propagate preferentially along the crack direction and forming a non-uniform deformation field bounded by the crack. The study revealed the micro-macro evolution patterns of progressive damage during creep in extremely weak fractured rock, providing theoretical support for early warning and control technologies against creep instability in tunnel rock masses of weakly cemented strata in western regions. Full article

(This article belongs to the Topic Advances in Mining and Geotechnical Engineering)

► Show Figures

Figure 1

13 pages, 3383 KB

Open AccessArticle

Rare-Earth Element Geochemistry for the Characterization of Sedimentary Environment and Provenance: A Case Study of the Eocene Liushagang Formation, Weixi’nan Sag, Beibuwan Basin, China

by Yang Su, Jie Chen and Jiao Wang

Geosciences 2026, 16(3), 105; https://doi.org/10.3390/geosciences16030105 - 3 Mar 2026

Viewed by 344

Abstract

This study investigates the rare-earth element (REE) geochemistry of twenty-nine clastic rock samples from the Paleogene Liushagang Formation in the Weixi’nan Sag. The primary objectives were to quantitatively evaluate the depositional paleoenvironment, determine the provenance lithology, and constrain the tectonic setting of the [...] Read more.

This study investigates the rare-earth element (REE) geochemistry of twenty-nine clastic rock samples from the Paleogene Liushagang Formation in the Weixi’nan Sag. The primary objectives were to quantitatively evaluate the depositional paleoenvironment, determine the provenance lithology, and constrain the tectonic setting of the source area. Results reveal distinct chondrite-normalized REE distribution patterns characterized by light REE (LREE) enrichment, relatively flat heavy REE (HREE) segments, and pronounced negative Eu anomalies. The cerium anomaly index (Ce_anom, normalized to the North American Shale Composite) ranges from −0.06 to 0.00, implying broadly suboxic to anoxic-reducing conditions in the water column during deposition. The chondrite-normalized (La/Yb)_N ratio, utilized as a proxy for relative depositional residence time, decreases stratigraphically from member 3 to member 1, reflecting a transition to shorter residence times and higher relative sedimentation rates. Laterally, (La/Yb)_N increases toward the basin center, accurately recording progressively lower sedimentation rates basinward. Provenance analysis indicates that the sediments were predominantly derived from felsic igneous rocks of the upper continental crust. Spatially, the northern steep-slope belt reflects a uniform source, whereas the southern gentle-slope belt and the Weixi’nan low-uplift periphery record multisource mixed inputs. Finally, tectonic discrimination reveals an “active continental margin” affinity. This geochemical signature represents the inherited tectonic environment of the Mesozoic parent rocks in the surrounding source uplifts, rather than the Cenozoic extensional rift setting of the Weixi’nan Sag itself. Full article

► Show Figures

Figure 1

16 pages, 8115 KB

Open AccessArticle

Fusing Deep Learning and Gradient Boosting for Robust Minute-Level Atmospheric Visibility Nowcasting

by Yuguo Ni, Chenbo Xie, Zichen Zhang and Jianfeng Chen

Geosciences 2026, 16(3), 104; https://doi.org/10.3390/geosciences16030104 - 3 Mar 2026

Viewed by 339

Abstract

Atmospheric visibility nowcasting is vital for safety-critical operations but remains challenging due to complex atmospheric dynamics. We propose a compact stacking ensemble merging a multilayer perceptron (MLP) and gradient-boosted regression trees (GBRT). The model, trained on seven months of minute-scale resolution data with [...] Read more.

Atmospheric visibility nowcasting is vital for safety-critical operations but remains challenging due to complex atmospheric dynamics. We propose a compact stacking ensemble merging a multilayer perceptron (MLP) and gradient-boosted regression trees (GBRT). The model, trained on seven months of minute-scale resolution data with a variability-adaptive filter to suppress sensor noise, employs cross-validation. Results demonstrate that the ensemble achieves its peak performance in the operationally critical low-visibility regime (V < 5 km). This range is particularly significant as it encompasses the Category I and II (CAT I/II) operational thresholds defined by the World Meteorological Organization (WMO) for aviation and surface transportation safety. In this regime, the ensemble yields an R² of 0.82 and an MAE≈385 m, significantly outperforming single learners during rapid weather transitions. Conversely, in the high-visibility regime (V > 20 km), the explanatory power decreases (R² of 0.46) due to inherent forward-scattering sensor uncertainties and low aerosol concentrations. Despite these range-specific physical limitations, the model maintains high robustness with narrowly centered residuals. This efficient approach, utilizing cost-effective in situ sensors, is highly suitable for airport and road-weather applications and offers strong potential for multi-site scalability. Full article

(This article belongs to the Section Climate and Environment)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Geosciences, Volume 16, Issue 3 (March 2026) – 43 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI