Geosystems and Geoenvironment最新文献

{"title":"Trace element geochemistry of mantle xenoliths from Zarnitsa kimberlite pipe, Daldyn field, Yakutia: Complex history of melts interactions with lithospheric mantle","authors":"I.V. Ashchepkov ,&nbsp;N. Ntaflos ,&nbsp;N.S. Medvedev ,&nbsp;G.P. Shmarov","doi":"10.1016/j.geogeo.2024.100313","DOIUrl":"10.1016/j.geogeo.2024.100313","url":null,"abstract":"<div><div>Mantle xenoliths from Zarnitsa pipe studied in gray eruptive breccias (early) brown autholitic breccia (BAB) and black macrocrystic kimberlites (last dike; BMK), include garnet and spinel dunites-harzburgites, pyroxenites, eclogites, glimmerites and megacrysts. PT reconstructions using xenoliths reveal sharply layered structure (8 levels), estimated with the single grain mineral estimates mark hot (Cpx, Ilm) and cold (OPx, Gar) inflected geotherm. The interaction with plume melts is found at the lithosphere asthenosphere boundary (LAB), pyroxenite layer (3-4 GPa), Gar-Sp transition and Moho. Eclogites reveal Fe# growth from LAB to middle pyroxenites layer. Clinopyroxenes and ilmenite estimates marks melt refertilisations in interlayers between coupled subduction slabs. Source of capture from first to third stage deepening to LAB and Cr- rich garnets (to 19.5 Cr₂O₃) are below the LAB.</div><div>The grey erupted breccia (GEB) includes mainly depleted and deformed peridotites. The later BAB includes pyroxenites, eclogites, and refertilised, deformed, and veined peridotites in BMK. Geochemistry of minerals changes from primary mid ocean ridge basalts (MORB) and back arc peridotites with low REE and large ion lithophile elements (LILE) and deeps in high field strength elements (HFSE) to metasomatized by alkaline (high Na and LILE) and adakitic melts (high Al, Na, Sr, and elevated HFSE) varieties and refertilised lherzolites due to plume at last stage. Mantle column metasomatized with scattered phlogopites in early grey eruptive breccia to amphibole-phlogopite ilmenite veins at last stages. Amphiboles trace mantle from lithosphere – asthenosphere boundary to Moho.</div><div>Growth of the diamond grade from early eruptive breccia to later kimberlite phases refer to decreasing of the crust material and deepening of the xenoliths capture level. Metasomatism dissolve the diamonds but growth of megacrystic diamond crystals increase diamond grade.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100313"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142704317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learning of Sentinel-1 SAR for burnt peatland detection in Ireland","authors":"Omid Memarian Sorkhabi","doi":"10.1016/j.geogeo.2024.100321","DOIUrl":"10.1016/j.geogeo.2024.100321","url":null,"abstract":"<div><div>Peatlands represent vital carbon reserves; however, once ignited, they release stored carbon, inflicting lasting environmental harm and necessitating prolonged recovery periods. An innovative method merging Sentinel-1 satellite imagery and deep learning (DL) is proposed to monitor burnt peat across diverse regions of Ireland, regardless of weather conditions or time of day. Sentinel-2 images and field measurements were used to train deep neural networks (DNN) and the accuracy in detecting burnt peat areas reached 80 %. This was achieved by combining the VV (vertical transmit, vertical receive) and VH (vertical transmit, horizontal receive) from Sentinel-1. Time-series analysis of Sentinel-1 VV backscatter change for Wicklow Mountains in 2018 highlights the Sentinel-1's capacity to detect various phenomena, including snowfall and burnt peat, evident prior to the peat fire event. Furthermore, an examination of peat fire occurrences in Wicklow Mountains from 2018 to 2023 through time series and mapping shows a significant escalation, with the largest burnt areas detected in 2023 spanning over 40 km².</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100321"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Cenozoic high and low temperature magma generation from primordial and age-modified mantle materials beneath Dariganga in Southeast Mongolia: Factors of mantle degassing and adiabatic upwelling","authors":"Sergei V. Rasskazov ,&nbsp;Irina S. Chuvashova ,&nbsp;Tatyana A. Yasnygina ,&nbsp;Elena V. Saranina","doi":"10.1016/j.geogeo.2024.100295","DOIUrl":"10.1016/j.geogeo.2024.100295","url":null,"abstract":"<div><div>Representative sampling of the Dariganga volcanic field was conducted to decipher its inner structure in terms of its deep magma sources. Rocks with a high La/Yb ratio (40–54) and a high MgO content (11–15.8 wt%) are identified among the predominantly moderate La/Yb ratio (7–40) and a moderate MgO content (5–11 wt%) rocks. These rock markers, traced along linear volcanic zones, are considered as indicators of high and low temperature magma generation processes. A general agreement exists that partial melting predominated in the transitional asthenosphere–lithosphere region; however, between 10 and 5 Ma, these processes were complicated by melts that either adiabatically ascended from a residual slab source in the deep mantle at a high potential temperature (Т_р = 1489°С) or were generated due to mantle fluid degassing at a low temperature or both these processes, simultaneously. Magmas were subsequently adiabatically upraised from an OIB-like source in the deep mantle with potential temperatures (T_p) of up to 1423°C and were also generated by mantle fluids at low temperature. The rock markers yield Pb-isotope age estimates of the proto-mantle (at 4.47 and 4.45 Ga) and the age-modified mantle (at 3.11 and 2.74 Ga) beneath Dariganga. In the last 16 Ma, encompassing the late geodynamic epoch of Earth's mantle, similar high and low temperature magmas have erupted across vast sections of the Japan-Baikal Geodynamic Corridor; these magmas are not reported from the adjacent Abaga and Dalinuoer areas, with the exception of the final (Holocene) fluid-derived compositions.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100295"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenetic and geochemical constraints on ca. 1.89–1.88 Ga Bastanar mafic dyke swarm, Bastar craton, India: Insights into MORB- and OIB-type contributions and interactions with metasomatized subcontinental lithospheric mantle","authors":"Ankur Ashutosh,&nbsp;Amiya K. Samal,&nbsp;Gulab C. Gautam,&nbsp;Rajesh K. Srivastava","doi":"10.1016/j.geogeo.2024.100267","DOIUrl":"10.1016/j.geogeo.2024.100267","url":null,"abstract":"<div><div>The Bastar craton of the Indian Shield hosts several generations of mafic dyke swarms of various trends, compositions, and ages, which span from ca. 2.7 Ga to 1.42 Ga. This study focuses on geochemical attributes of the ca. 1.89–1.88 Ga NNW-trending Bastanar swarm, aiming to address a perceived discrepancy between its arc-like geochemistry and the influence of a heterogeneous mantle source. To resolve the intra-swarm geochemical variations, we conducted a comprehensive geochemical characterization and petrogenetic interpretation of the ca. 1.89–1.88 Ga Bastanar swarm. The samples from this swarm are categorized into two distinct groups, primarily based on their geochemical composition. The Group 1 samples exhibit higher TiO₂ (1.06–1.86 wt%), (La/Yb)_N (7.2–8.6), (Gd/Yb)_N (2- 2.27), Nb (14.6–16.6 ppm), Th (1.23–3.03 ppm) and Zr (104–118.72 ppm) concentrations than the Group 2 samples. Furthermore, rare-earth element patterns and variations in high-field strength element contents in the Group 1 samples suggest derivation from a deeper, less depleted mantle source resembling an OIB/less MORB-type. This inference is further supported by higher TiO₂/Yb, Zr/Nb, and Nb/Y ratios. In contrast, the Group 2 samples indicate derivation from a shallower, more MORB/less OIB-type depleted mantle source, as evidenced by lower TiO₂/Yb, Zr/Nb, and Nb/Y ratios. Variations in Dy/Yb and Gd/Yb ratios confirm the involvement of variable mantle sources, implying the derivation of the Group 1 and 2 samples from garnet-rich and spinel-rich lherzolite mantle sources, respectively. The absence of consistent negative Nb-Ta-Ti anomalies in the Group 1 samples suggests an uncontaminated nature, ruling out any role of crustal contamination. On the other hand, the Group 2 samples display negative Nb-Ta-Ti anomalies with enriched LREE and LILE patterns, indicating the involvement of crustal components in their genesis. A trace-element modelling suggests that the ca. 1.89–1.88 Ga mafic dyke swarm exhibits significant intra-swarm variability, with at least two distinct source components contributing to its genesis – a depleted MORB-type and an enriched OIB-type mantle. Notably, the geochemical characteristics of the Group 2 samples suggest interaction with a metasomatized mantle source, possibly enriched by fluids from an earlier subducted slab. Geochemical evidence presented in this work supports Archean subduction-related processes for the crustal growth of the Bastar craton and highlight the enduring influence of a metasomatized sub-continental lithospheric mantle on subsequent magmatism over millions of years.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100267"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140085401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of top depth to underground targets of Karous-Hjelt and Fraser filtering of VLF-EM measurements: The Thumb's rule approach","authors":"Joseph Omeiza Alao ,&nbsp;Kolawole Muideen Lawal ,&nbsp;Bala Bello Muhammad Dewu ,&nbsp;Jimoh Raimi","doi":"10.1016/j.geogeo.2024.100319","DOIUrl":"10.1016/j.geogeo.2024.100319","url":null,"abstract":"<div><div>Prediction of the exact location and depth of underground targets with the very low-frequency electromagnetic (VLF-EM) technique is one of the most important and difficult tasks in geophysical investigations. This study examined and compared the conventional 2D KIFFILT inversion pseudo-section and the use of Thumb's rule technique in the Fraser filter plot to estimate the top depth of underground targets. The VLF-EM measurement was performed over several empirical buried target models to identify anomalies or geophysical responses corresponding to subsurface targets. The Karous-Hjelt and Fraser filtering techniques were applied to estimate the depth of the identified anomalies using Thumb's rule and the conventional 2D KIFFILT inversion. The signal behaviours of the VLF-EM current density pseudo-sections and the application of Thumb's rule effectiveness in delineating empirical buried target models were examined. Thumb's rule shows 65 % accuracy with the actual depth of the empirical buried target models, while the conventional 2D KHFFILT inversion shows 30 % accuracy with the actual depth of burial. Thumb's rule is more effective and precise in predicting the accurate depth of underground targets. The influences of conductive and resistive materials on VLF-EM signals and the challenges of VLF-EM surveys were discussed. Thumb's rule is suggested as a substantial technique for estimating top depth to the underground target where depth estimation is of prime interest due to its large degree of accuracy. In addition, the total depth of the current density distribution was noted to be increased when the distance between measuring points increased. This means that VLF-EM signals with longer wavelengths indicate deeper depth penetration into the ground than signals with shorter wavelengths. The accuracy of Thumb's rule regarding top depth estimation of the anomalies has been successfully tested and validated, which can be used for VLF-EM investigation where accurate depth estimation is required. The VLF-EM technique can be considered reliable for depth estimation using Thumb's rule approach, which applies to a wide range of subsurface investigations.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100319"},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quaternary surface development in the frontal Mikir massif, NE India: A possible key to understand the tectonic controls and geotechnical significance","authors":"Manash Protim Baruah ,&nbsp;Devojit Bezbaruah ,&nbsp;Tapos K. Goswami","doi":"10.1016/j.geogeo.2024.100318","DOIUrl":"10.1016/j.geogeo.2024.100318","url":null,"abstract":"<div><div>Quaternary geological mapping has been carried out in the south-eastern frontal part of the Mikir massif in northeastern India. Geomorphological and surface geological studies have led to the delineation of three Quaternary surfaces viz., S1, S2, and S3, in the order of decreasing antiquity. A preliminary assessment of the prevailing active tectonics has been achieved through seismotectonic study by analyzing seismic events for the period 1988–2013. Episodic reactivation of the Dhansiri Fault, Barpathar Fault and Kaliyani Shear Zone is evident by the presence of epicentral clusters along these faults. Field evidence of active tectonics, such as steep scarp faces, damming effects, and pressure ridges, also confirms the prevailing neotectonics in the area. The proposed tectonic model for the deposition of Quaternary surfaces shows that the Naga Thrust and its subsidiary splays (Barpathar Fault) control the present-day disposition of these surfaces. Geotechnical evaluation of soil samples shows that soils of S1 surface are having low shear strength, high liquid limit, and high compressibility index. Whereas samples from the S2 surface show low liquid limit, low compressibility index, high cohesiveness, and higher angle of internal friction. Hence, these S2 surfaces provide the best foundation strata for the construction of any civil engineering structures in the area.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100318"},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pyroxene-rich Orange sand highway from basaltic highlands to the ocean: Modern sediment-routing system of an Early Jurassic river","authors":"Eduardo Garzanti ,&nbsp;Guido Pastore ,&nbsp;Sergio Andò ,&nbsp;Marta Barbarano ,&nbsp;Alberto Resentini ,&nbsp;Giovanni Vezzoli ,&nbsp;Pieter Vermeesch ,&nbsp;Pedro Dinis ,&nbsp;Annette Hahn ,&nbsp;Errol Wiles ,&nbsp;Lindani Ncube ,&nbsp;Helena-Johanna Van Niekerk","doi":"10.1016/j.geogeo.2024.100311","DOIUrl":"10.1016/j.geogeo.2024.100311","url":null,"abstract":"<div><p>Studying the origin of rivers, the development of drainage through geological time, and the multiple processes that affect the composition of the sediment is a fascinating scientific adventure. This article probes into modern sedimentary processes in the Orange River catchment, which covers much of South Africa, and monitors changes in petrographic, mineralogical, geochemical, and geochronological signatures along the ∼4000 km-long fluvial and coastal conveyor belt that transferred pyroxene-rich and diamond-bearing sand from Lesotho to Angola.</p><p>The Orange River, established as early as the Early Jurassic as a classic example of dome-flank drainage, is perhaps the oldest river on our planet. A quarter of Orange sand is supplied by the erosion of Lesotho basaltic highlands, reaching 3482 m a.s.l. and representing a remnant of one of the most extensive magmatic effusions of Phanerozoic history, the Lower Jurassic Karoo lavas. Basaltic lavas, dolerite sills and dykes shed rock fragments and clinopyroxenes that constitute the unique fingerprint of Orange River sand. Only a tenth of the sediment is supplied by the Vaal River, the longest Orange tributary that drains siliciclastic and volcanic units ranging in age from Neoarchean in the Transvaal to early Mesozoic in the Karoo Basin. In the arid middle and lower reaches, the Orange River carves its course into the Namaqua Belt and receives the Molopo River flowing only episodically across the vast Kalahari Desert and the Fish River draining sedimentary rocks of the Nama Group and Karoo Supergroup. Fragile sedimentary rock fragments do not survive high-energy wave transport, but basaltic rock fragments and pyroxenes do, allowing us to trace sand transport for ∼1800 km all along the Atlantic coast of Namibia to as far as southern Angola. Understanding sediment mass transfer has scientific as well as practical interest, being a prerequisite for effective fluvial and coastal management, with particular economic significance in the special case of diamond-bearing Orange sand.</p></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100311"},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S277288382400061X/pdfft?md5=886caada2bdd040ca4a528e01305c306&pid=1-s2.0-S277288382400061X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142151700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemometric heavy metal contamination in tropical Indian estuaries: Implications for source identification","authors":"N. Kirubakaran ,&nbsp;D. Senthil Nathan ,&nbsp;M. Sridharan ,&nbsp;S. Harikrishnan ,&nbsp;M. Rajamanickam ,&nbsp;N. Anbuselvan","doi":"10.1016/j.geogeo.2024.100316","DOIUrl":"10.1016/j.geogeo.2024.100316","url":null,"abstract":"<div><p>The impact of urban and industrial effluents in the tropical Indian estuaries (Ariankuppam backwater and Chunnambar River), east coast of India have been investigated in the present study by determining the degree of heavy metals contamination of the estuarine sediments. A total of 30 surface sediment samples were collected from both estuaries and were analyzed for trace metals, grain size and organic matter. The granulometric analysis reveals that both the estuaries are predominated by silty sand to sandy silt. The significant amount of organic matter (OM) in the Ariankuppam estuary sediment is due to natural (mangroves) and anthropogenic (pollution) organic input. Pearson correlation analysis reveals that there was a strong negative correlation of sand fraction with other sediment variables (silt, clay, and organic matter) and heavy metals, whereas a positive correlation was observed between silt+clay, organic matter, and heavy metals. The significant positive correlation of Fe with Ni, Cu, Pb and Zn presents Fe-Mn oxyhydroxides are the main controlling factor of heavy metals in both estuarine sediments. Cluster analysis and PCA helped to discriminate the station groups along both estuaries according to their sediment components and heavy metals. This study also revealed that sediment grain size is a key factor influencing organic matter and heavy metal accumulation in surface sediments. The calculated pollution indices such as Contamination factor (CF), Geoaccumulation Index (Igeo) and Pollution Load Index (PLI) values indicate that both estuaries are moderate to highly contaminated by Co and low to moderately contaminated by Pb and Zn. Based on the factor analysis, it is presumed that river runoff and industrial and untreated domestic wastes from lands are responsible for increased heavy metal concentration in both estuaries. Increased levels of metal contamination along the Union Territory of Puducherry coastline may increase the risk of human exposure to metals through the consumption of seafood, making the need for tougher regulations on the discharge of metals into the environment even more important.</p></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100316"},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772883824000669/pdfft?md5=bfe072acae30077c27c1e9bc36bb8445&pid=1-s2.0-S2772883824000669-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142172147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A robust ensemble of hybrid and bivariate statistical models for flood prediction mapping in Lower Damodar River Basin of India","authors":"Shuayb Abdinour Osman ,&nbsp;Jayanta Das","doi":"10.1016/j.geogeo.2024.100312","DOIUrl":"10.1016/j.geogeo.2024.100312","url":null,"abstract":"<div><p>This research explores flood prediction in the Lower Damodar River Basin (LDRB) using a hybrid ensemble of a Naïve Bayes Tree (NBT) and five bivariate statistical models such as Evidential Belief Function (EBF), Index of Entropy (IOE), Frequency Ratio (FR), Statistical Index (SI), and Modified Information Value (MIV). A total of 348 flood locations and 15 conditioning factors including hydrological, topographical and land cover were considered for this analysis. To ensure the precision of model predictions, a multicollinearity assessment was executed. Receiver operating characteristic (ROC) curve, area under curve (AUC), mean absolute error (MAE), mean squared error (MSE), and root mean squared error (RMSE) were performed to compare and asses each of the models all. The results reveal that all models performed well in creating flood hazard maps with AUC &gt;0.8 and RMSE &lt;0.4. FR and EBF models demonstrated the highest predictive accuracy (AUC=0.85), followed by the IOE, SI, and MIV models. The ensemble of NBT with bivariate models shows promising results, showcasing reduced error metrics and improved accuracy for the IOE, SI, and MIV models. This study highlights the potential of ensemble models in flood hazard prediction, offering valuable insights for global flood risk management. The successful application of these data-driven models showcases their importance in forecasting flood risks, aiding decision-makers and planners in developing more effective flood mitigation strategies.</p></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100312"},"PeriodicalIF":0.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772883824000621/pdfft?md5=c5d1c08f3c4d9022ddbf80e95b6d5637&pid=1-s2.0-S2772883824000621-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142095482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resurgent dome and super-hot enhanced geothermal system: The Sahinkalesi Massif within the Hasandag Stratovolcanic Province, Central Anatolia, Turkey","authors":"Dornadula Chandrasekharam ,&nbsp;Mrityunjay Singh ,&nbsp;Alper Baba ,&nbsp;Ingo Sass","doi":"10.1016/j.geogeo.2024.100314","DOIUrl":"10.1016/j.geogeo.2024.100314","url":null,"abstract":"<div><p>The Sahinkalesi, a volcanic dome located NNE of Hasandağ, Türkiye exhibits anomalous heat flow value, geothermal gradient and the Curie point depth is located at very shallow depth in this region. Our investigation indicates presence of super-critical thermal regime (378°C) at about 4 km depth and the MT analysis indicate shallow magma chamber at about 5 km depth. The crust is relatively thin below this region with the low-velocity region located at depth of about 36 km. Thermo-Hydro-mechanical model investigation has been carried out using finite element discretization technique. For faulted zone reservoir models, 30 years of geothermal energy exploitation does not cause thermal breakthrough for mass flow rates up to 500 kg/s, however, the mean stress developed in the reservoir becomes much larger and may be unsustainable for the reservoir stability. To ensure the success of a fractured reservoir model, the use of multiple wellbores is recommended. In the case of a closed-loop geothermal system, the primary concern is the control of thermoelastic stress. This can be achieved either by increasing the wellbore depth while reducing the injection mass flow rate, or by extending the wellbore's horizontal component. The outlet temperature in both the cases maintained at 275°C. This is the first time a superhot EGS site has been identified in Türkiye.</p></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100314"},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772883824000645/pdfft?md5=caf4e52bcc932af83f0874633f27c01f&pid=1-s2.0-S2772883824000645-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}