Solid Earth Sciences最新文献

{"title":"Tracing the evolution of shallow geothermal springs in the Shyok−Nubra Valley of North-West Himalayas, India through hydrogeochemistry and stable isotopes (δ18O, δD)","authors":"Parashar Mishra ,&nbsp;Archisman Dutta ,&nbsp;Ahsan Absar ,&nbsp;Vivek Prakash Malviya ,&nbsp;Pankaj Saini ,&nbsp;Ayodhaya Prasad Thapliyal ,&nbsp;Sayandeep Banerjee","doi":"10.1016/j.sesci.2024.100175","DOIUrl":"https://doi.org/10.1016/j.sesci.2024.100175","url":null,"abstract":"<div><p>A conceptual model has been proposed based on water samples collected from geothermal springs in the Shyok suture zone of North-West Himalayas, Ladakh geothermal province, India by nurturing hydrogeochemistry, mineralogical insights, and stable isotopic (δD, δ¹⁸O) systematics. The reservoir rock is comprised of granitic segment with intrusion of volcano-plutonics and a variety of meta-sedimentaries which becomes more exposed towards western side of the valley in the form of Shyok Ophiolitic melange. Thermal waters, located above 3100 m above msl, with variable genetic classification (Changlung: Na–HCO₃; Panamik: both Na–HCO₃ and mixed type; Pulthang: purely mixed type), have TDS and temperature lying between 587 and 2278 mg/L and 28−78 °C, respectively. High concentration of trace elements (Li, B, As, Cs, Rb, W) in geothermal fluids points to the magmatic origin regarding their enrichment mechanism. Surface manifestation of hydrothermal/evaporitic minerals like thenardite, trona, sylvite, halite, nahcolite, thermonatrite, etc. establishes a signature of high-temperature at shallow level of reservoir and their dissolution kinetics decipher origin of solutes apart from weathering of alkali/alkaline aluminosilicates. Utilizing empirical chemical geothermometry and Si-Enthalpy mixing modelling, the estimated reservoir temperatures exhibit significant variability ranging from 100 to 210 °C and reservoir silica concentration 382 mg/L with average circulation depth of geothermal waters around 1.8 Km and fluid residence time of 2640 years. The Shyok-Nubra springs liberate substantial amount of CO₂-enriched water, with degassing flux of 6.26 × 10⁵ mol of CO₂/year. δD and δ¹⁸O systematics reveal that geothermal springs are recharged by meteoric water, snow-melt and magmatic fluid with cold-water component of 27.1–62.4% mixed with hot fluids. Thermal springs are recharged from a single reservoir source located a shallow level towards North-West of Changlung having large lateral flow of about 25 Km generating Panamik and Pulthang fluids with subsequent dilution. This study highlights the extent and consequences of water–rock interaction across diverse lithologies (granite and mafic volcanics) in the Himalayas, emphasizing its implications over fluid circulation time and subsurface temperature considerations which rationalizes the evolution of geothermal fluids.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 2","pages":"Article 100175"},"PeriodicalIF":2.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000138/pdfft?md5=4a81d5bcb869b5acf2b7196b84fd2a96&pid=1-s2.0-S2451912X24000138-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140543358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural modeling of the southern Kohat Basin and Frontal Ranges; implications for tectonic evolution and hydrocarbon play","authors":"Nazir-ur- Rehman ,&nbsp;Sajjad Ahmad ,&nbsp;Shah Faisal ,&nbsp;Shuja Ullah ,&nbsp;Mumtaz Ali Khan ,&nbsp;Fakhrul Islam","doi":"10.1016/j.sesci.2024.100165","DOIUrl":"https://doi.org/10.1016/j.sesci.2024.100165","url":null,"abstract":"<div><p>More recently Kohat's fold-thrust belt, including the Karak area has emerged as an important hydrocarbon fertile region of the western Himalayan orogenic system. The Eocene and Paleocene strata, including mechanical weak Eocene units representing a shallow decollement have a noticeable contribution to the deformation style and petroleum system of the area. In the present study, surface mapping is integrated with seismic information to elucidate the structural style of the Karak area, the data reveal that there are two different structural entities, separated by Karak Fault Zone. The northern domain portrays salt diapiric structures representing doubly plunging and complexity overturned, and fault bounded folds' geometries. However, in the subsurface below the Eocene sequence, the deformation is characterized by south-directed imbricate thrust system. In contrast, because of the absence of Eocene salt horizon, the southern domain of the Karak area illustrates a brittle style of deformation, mimicking fault propagation folding. In addition, an array of south-verging imbricate system from a regional basal decollement translates rock as old as Permian along the Surghar range frontal thrust. It can be observed that fault geometry and fold styles in the north and south of Karak Fault Zone are entirely different. Restored cross-sections across the area indicate 35% of shortening has been accommodated in the area. Moreover, from the present study it has been concluded that in the purlieu of Karak Fault Zone, possibly occupy auspicious structural traps at top Paleocene Lockhart level.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 2","pages":"Article 100165"},"PeriodicalIF":2.0,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000035/pdfft?md5=1a97c8f27a62fdbc251faaac5b2fb37f&pid=1-s2.0-S2451912X24000035-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140063106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Megacrystals of chrysotile discovered in fully-serpentinized jianite","authors":"Xi Liu,&nbsp;Haoqiang Li,&nbsp;Mingyue He","doi":"10.1016/j.sesci.2024.100166","DOIUrl":"https://doi.org/10.1016/j.sesci.2024.100166","url":null,"abstract":"","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 1","pages":"Article 100166"},"PeriodicalIF":2.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000047/pdfft?md5=2d0ed84e51cfb62797811f7bf7dd42fb&pid=1-s2.0-S2451912X24000047-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140014004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical maturity, litho-tectonic settings and source area paleoweathering characterization of the Cretaceous Mundeck and Mungo River Formation sandstones, North Western, Douala sub basin, West Africa: A petrographic and geochemical approach","authors":"Mokake Esue Fidelis ,&nbsp;Mary Ewokolo Moloua Etutu ,&nbsp;Bisse Salomon Betrant ,&nbsp;Bokanda Ekoko Eric ,&nbsp;Florence Njinto Kwankam ,&nbsp;Victor L. Wotany ,&nbsp;Lemnyuy Prosper Yiika ,&nbsp;E. Mengu Emmanuel ,&nbsp;Njoh, N. Clevis ,&nbsp;N. Nfor Shannon ,&nbsp;Patrick Mendi Wajiba ,&nbsp;Chin Thiery Berinyuy ,&nbsp;Kah Odilia Sih ,&nbsp;Christorpher M. Agyingi","doi":"10.1016/j.sesci.2024.01.002","DOIUrl":"https://doi.org/10.1016/j.sesci.2024.01.002","url":null,"abstract":"<div><p>The Mundeck and Mungo River Formation sandstones located within the Douala sub basin in Cameroon were subjected to both petrographic and geochemical analyses to unveil their geological characterization such as chemical and mineralogical maturity, litho-tectonic setting, climate and weathering intensity of the source area at the time of their formation. Petrographic studies reveals that the sandstones show variable colours ranging from reddish to brownish, pinkish, grey and white with textures ranging from medium to coarse grained. The studied sandstones consist of various types of angular to sub angular, quartz, rock fragments, mica, feldspar. Modal analysis data and plots of detrital modes of the studied sandstones on Qt–F–RF diagrams suggest that they were derived from a plutonic source rock (igneous origin) with little or no contribution from metamorphic sources. Plot of the Qm–F–L diagram of the studied sandstones reveal a quartzose recycled and transitional continental provenance fields. Mineralogical classification of these sandstones from Qt–F–RF triangular diagram classifies them as arkose, lithic arkose and sub-litherarenite. Bivariate plot of Qp/(F + R) <em>vs</em> (Qm + Qp)/(F + R), SiO₂ Vs Al₂O₃ +K₂O + Na₂O coupled with values of Chemical index Alteration (CIA = 70–99) and plagioclase index Alteration (PIA&gt;80) reveal a moderate to high intensity of weathering in the source area under a semi-humid to humid paleoclimatic conditions with high lixiviation of feldspars (PIA&gt;80 %) for the studied sandstones. The mineralogical maturity index (MMI = 3–9) coupled with the new index of compositional variation (ICV_new &lt;1) reveal that the sandstones are sub mature to mature. Geochemical binary plots of La/Sc, Th/Co, Th/Sc couple with plots of DF1vs DF2 and K₂O/Na₂O <em>vs</em> SiO₂ points to an igneous felsic source rock formed in a passive margin for the studied sandstones.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 1","pages":"Article 100164"},"PeriodicalIF":2.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000023/pdfft?md5=4b08e3cd1639d14ac42c7ddac0f63b6c&pid=1-s2.0-S2451912X24000023-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139674770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemistry of apatite from Zhuxiling tungsten deposit, eastern China: A record of magma evolution and tungsten enrichment","authors":"Likai Ge,&nbsp;Qiaoqin Xie,&nbsp;Jun Yan,&nbsp;Shan Huang,&nbsp;Liu Yang,&nbsp;Quanzhong Li,&nbsp;Jiancheng Xie","doi":"10.1016/j.sesci.2024.01.001","DOIUrl":"https://doi.org/10.1016/j.sesci.2024.01.001","url":null,"abstract":"<div><p>The origin and evolution of tungsten ore, a key metal resource, have long been controversial. In order to reveal the origin of tungsten mineralization related to weakly fractionated I-type granites, we have carried out detailed in situ element analysis on apatite from gabbro-diorite enclaves and their host rocks (biotite granodiorites) in Zhuxiling deposit, Jiangnan orogenic belt. The groups of apatite samples were identified, respectively from gabbro-diorite enclaves (Group A) representing deep early magma, and biotite granodiorites with weak tungsten mineralization stage (Group B) and strong tungsten mineralization stage (Group C). The three-group apatite samples with high F (2.15–4.74 wt.%) and low Cl (&lt;0.19 wt.%) contents, belong to fluoroapatite, and have LREE enrichment, negative Eu anomalies (Eu/Eu∗ = 0.27–0.52), and low Sr/Y ratios (mainly &lt;1). The Sr content difference between the apatite studied and host rocks, and the gradual increase of Sr contents from Group A to Group B to Group C, indicate that high tungsten content magma mixing is the dominant cause of mineralization in the Zhuxiling region. The studied apatite samples with different internal zonal textures, suggest that more significant oscillatory growth zone is associated with higher tungsten content, more complex internal compositions, and longer crystallization times. Apatite trace elements (e.g., Sr, Y, Eu/Eu∗, REE) characteristics indicate that the Zhuxiling mineralized intrusions mainly experienced shallow feldspar crystalline differentiation. The F- and Li-rich, high evolution degree, and moderate oxygen fugacity of magma may contribute to tungsten mineralization in the Zhuxiling region.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 1","pages":"Article 100163"},"PeriodicalIF":2.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000011/pdfft?md5=fb144e05328940a25163c1aa32e0fc15&pid=1-s2.0-S2451912X24000011-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139652811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The solubility and complexation of Niobium in hydrothermal fluids","authors":"Haotian Liu ,&nbsp;Xing Ding ,&nbsp;Haibo Yan ,&nbsp;Kaixuan Liu ,&nbsp;Junfeng Liu ,&nbsp;Xiaolong Huang","doi":"10.1016/j.sesci.2023.12.001","DOIUrl":"https://doi.org/10.1016/j.sesci.2023.12.001","url":null,"abstract":"<div><p>Metal dissolution, complexation, and speciation are the key processes that facilitate metal mobilization and transport in fluids. Niobium (Nb), a kind of critical metal, has traditionally been regarded as a fluid-immobile element; however, it sometimes shows apparent hydrothermal mobility and even mineralization. Studying the solubility and complexation of Nb in fluids is thus crucial for understanding its dissolution, transport, enrichment, and mineralization. In this paper, we reviewed the geological observations on Nb mobility related to magmatic-hydrothermal and metamorphic fluid activities, especially compiled and reprocessed the published data on Nb solubility and related thermodynamic calculation to discuss the complexation and speciation of Nb in fluids. Previous solubility experiments demonstrate that Nb has much higher solubility in F-bearing solutions than in other solutions (Cl⁻, ClO₄⁻, CO₃²⁻, HCO₃⁻, OH⁻, SO₄²⁻, etc.), the maximum of which is up to ∼3 wt% in a 2 mol/kg HF solution. It is revealed that Nb solubility is related to the solution's composition, pH, ionic strength, oxygen fugacity, temperature, and pressure. High solubility could be found in neutral and weakly-basic solutions at near ambient temperature and pressure or in F-bearing fluids at high-temperature and high-pressure conditions. Modeling calculations show that Nb could be soluble and stable in fluids as the mononuclear or polynuclear complexes, such as fluoride complexes, hydroxide complexes, chloride complexes, and hexametalate ions, etc. Thereinto, Nb–OH–F complexes should play a dominant role in Nb hydrothermal mobility and be enriched in medium–high temperature, acidic, and F-bearing fluids. Experiments and modeling calculation have also inferred the existence of the species (e.g., <span><math><mrow><mtext>Nb</mtext><msub><mrow><mo>(</mo><mtext>OH</mtext><mo>)</mo></mrow><mrow><mn>4</mn><mo>+</mo><mi>y</mi></mrow></msub><msup><mi>F</mi><mrow><mi>y</mi><mo>−</mo></mrow></msup></mrow></math></span>, <span><math><mrow><mtext>Nb</mtext><msub><mrow><mo>(</mo><mtext>OH</mtext><mo>)</mo></mrow><mrow><mn>3</mn><mo>+</mo><mi>y</mi></mrow></msub><msubsup><mi>F</mi><mn>2</mn><mrow><mi>y</mi><mo>−</mo></mrow></msubsup></mrow></math></span>, and <span><math><mrow><mtext>Nb</mtext><msub><mrow><mo>(</mo><mtext>OH</mtext><mo>)</mo></mrow><mrow><mn>2</mn><mo>+</mo><mi>y</mi></mrow></msub><msubsup><mi>F</mi><mn>3</mn><mrow><mi>y</mi><mo>−</mo></mrow></msubsup></mrow></math></span>), in which the F coordination number is no more than 3. Considering that it could have higher F contents than the experimental solutions (F &lt; 4 wt%), we believe that natural mineralized F-rich fluids would facilitate the formation of the species with higher F coordination numbers due to the positive relationship between the F coordination number in the species and F content in fluids","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"9 1","pages":"Article 100162"},"PeriodicalIF":2.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X2300048X/pdfft?md5=93401c0a514d356ffb21056ee20d2bfb&pid=1-s2.0-S2451912X2300048X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139652812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Zr solubility in mantle minerals at zircon saturation: Implications for zircon genesis in ultramafic rocks","authors":"Mengfei Ruan ,&nbsp;Jintuan Wang ,&nbsp;Xiaolin Xiong ,&nbsp;Li Li","doi":"10.1016/j.sesci.2023.10.002","DOIUrl":"10.1016/j.sesci.2023.10.002","url":null,"abstract":"<div><p>Metasomatic zircons in ultramafic rocks are crucial in tracking orogenic processes. Metasomatic zircons are conceived to form by local zircon saturation resulting from effective Zr transport during metamorphic events and incomplete Zr accommodation in mantle minerals. However, the accommodation capacity of Zr in mantle minerals remains unknown, hampering our understanding of zircon genesis in ultramafic rocks. Here we performed experiments at 2.0−6.0 GPa and 1050−1200 °C and determined Zr content (solubility) in the mantle minerals at zircon saturation (ZCZS). The results show that ZCZS values for the main mantle minerals are olivine (ol, 3.68 ± 0.27 ppm) &lt; orthopyroxene (opx, 4.67 ± 0.23 ppm) &lt; clinopyroxene (cpx, 28−1403 ppm) ≤ garnet (grt, 294−2222 ppm) with ZCZS for amphibole (amp, 189−546 ppm) and magnetite (mag, 263−630 ppm) overlapping that for cpx and grt under the experimental conditions. The significant variations of ZCZS for cpx and grt depends on mineral composition and P−T conditions. In detail, the ZCZS for cpx increases with temperature, Al₂O₃ content of cpx, and decreases with pressure; that for grt increases with temperature and X_Alm (molar fraction of almandine) in garnet. Important implications of this study include: 1) Considering the very low ZCZS for ol and opx, dunite and harzburgite are prone to zircon saturation during the infiltration of Zr-bearing metamorphic agents; 2) Because garnet is the main reservoir of Zr in garnet peridotite, metamorphic decomposition of garnets may produce inter-granular zircons; 3) The ZCZS for garnet excellently correlates with X_Alm and T, providing a potential geo-thermometer for garnet-bearing zircon saturated rocks.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"8 4","pages":"Pages 283-294"},"PeriodicalIF":2.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X23000387/pdfft?md5=25076f6b44bcdcc240d34580fe6a30aa&pid=1-s2.0-S2451912X23000387-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138620682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Zircon Hf isotopic compositions of the basement gneiss in Bayan Obo: Constraints on crustal evolution of the Yinshan Block in the North China Craton","authors":"Ying Wei ,&nbsp;Ming-Xing Ling ,&nbsp;Hong Zhang ,&nbsp;Yu-Long Liu ,&nbsp;Xiao-Yong Yang","doi":"10.1016/j.sesci.2023.09.001","DOIUrl":"10.1016/j.sesci.2023.09.001","url":null,"abstract":"<div><p>Bayan Obo, located in the north margin of the Yinshan Block, North China Craton (NCC), contains the Archean to Paleoproterozoic basement rocks which may shed light on the early crustal evolution of the NCC. In this paper, to reveal the formation and modification of the basements, we report Hf isotope of zircons from the biotite plagiogneisses in Bayan Obo. Combined with the published U–Pb ages and Hf isotope compositions of the zircons from the Bayan Obo basement rocks, a comprehensive review was employed to provide new insights into the formation and modification of the basement in this area. The oldest formation age of the basement rocks was found to be approximately 2.6 Ga, with positive <em>ε</em>_<em>Hf</em><em>(t)</em> values indicating the contribution from the depleted mantle to the rocks. The age of ∼2.0 Ga marks the major formation period of the basement rocks. The varied <em>ε</em>_<em>Hf</em><em>(t)</em> values (−17.2 to +8.9) of the magmatic zircons suggest a mixture origin between the depleted mantle and crustal rocks for the gneiss. The basement went through extensive metamorphism during 1.95–1.9 Ga. In addition, zircon U–Pb–Hf isotope data of the Precambrian units in Guyang and Wuchuan, which are adjacent to Bayan Obo, were compiled for comparison. The comprehensive review on the data of the concordant magmatic zircons indicates the existence of 3.5 Ga crustal fragments in the Yinshan Block. The melting of the depleted mantle and the addition of juvenile materials into the crust at 2.6–2.9 Ga and 2.45–2.55 Ga were confirmed by the high positive <em>ε</em>_<em>Hf</em><em>(t)</em> values of the magmatic and inherited zircons. An increase in remelting of the crust at 2.0 Ga is deduced from the extremely unradiogenic Hf isotope of the magmatic zircons.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"8 4","pages":"Pages 255-266"},"PeriodicalIF":2.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X23000363/pdfft?md5=d6225c370defe5b72593f73965cd0463&pid=1-s2.0-S2451912X23000363-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134993811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Texture and trace element characteristics of quartz in the Dongyuan porphyry W deposit, eastern China","authors":"Liu Yang,&nbsp;Yuanyuan Tian,&nbsp;Quanzhong Li,&nbsp;Jun Yan,&nbsp;Jiancheng Xie","doi":"10.1016/j.sesci.2023.11.001","DOIUrl":"https://doi.org/10.1016/j.sesci.2023.11.001","url":null,"abstract":"<div><p>Most W mineralization in the world is genetically related with highly fractionated granites, but little is known about ore-forming fluid evolution of W mineralization associated with weakly fractionated granites. To reveal the ore-forming fluid evolution of W mineralization related to the weakly fractionated granites, a combined study of field and petrographic observations, mineralogical, morphological, and in-situ geochemical data of different-type quartz from Dongyuan porphyry W deposit in the world-class Jiangnan W belt, China, was carried out. The petrographic observation and cathodoluminescence (CL) imaging revealed the quartz in the Dongyuan W deposit can be divided into hydrothermal quartz (Qz1 with core-edge structure, and Qz2 with oscillating zone) in the mineralized alteration zone, and magmatic quartz (Qz3 with inherited core) in granodiorite porphyry. The LA-ICP-MS results of the Dongyuan quartz samples show that Al may enter the quartz structure with trivalent Al³⁺ instead of Si⁴⁺, monovalent alkali metals and bivalent (Ge²⁺, Sr²⁺) cations is mainly of charge compensators in quartz, while Ti possibly is in the form of microinclusions of titanium-containing minerals in quartz. The integrated interpretation of the trace element compositions (e.g., Al and Ti contents, Al/Na ratios) and CL texture of quartz indicate high temperature (&gt;400 °C) and uniform Al-rich acidic fluid are conducive to W precipitation of the Dongyuan deposit. Furthermore, trace element compositions (e.g., Ge, Al) and micro-textures of quartz have the potential for distinguishing magmatic and hydrothermal quartz in the Dongyuan W deposit.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"8 4","pages":"Pages 305-318"},"PeriodicalIF":2.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X23000405/pdfft?md5=9c41d4d4caef17f926d9fa42aa64a75d&pid=1-s2.0-S2451912X23000405-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138839289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-criteria groundwater potential zonation using GIS-based fuzzified AHP: Case study of Ondo metropolis Southwestern Nigeria","authors":"Olumuyiwa Olusola Falowo ,&nbsp;Olajumoke Ojo","doi":"10.1016/j.sesci.2023.11.002","DOIUrl":"10.1016/j.sesci.2023.11.002","url":null,"abstract":"<div><p>The study utilized the fuzzy analytical hierarchical process (F-AHP) in the multicriteria decision analysis of seven important hydrogeologic parameters associated with groundwater potentiality/yield. The purpose was to develop groundwater potential map using groundwater potential index values (GWPIV) for Ondo metropolis, Southwestern Nigeria. The hydrogeologic parameters were prioritize and assigned different weights hierarchically according to their level of importance using F-AHP, as aquifer layer thickness (0.05), aquifer layer resistivity (0.04), overburden thickness (0.12), transverse resistance (0.18), transmissivity (0.32), coefficient of anisotropy (0.25), and formation factor (0.03). From regional perspective, based on drainage basin, and river network, the region was categorized to be of low/moderate groundwater yield, with moderate to high flow connectivity. The higher and lower elevations are generally remarkable in the northern and southern areas respectively, hence possibility of movement of water towards the southern part with the northern forming the watershed. Furthermore, the longitudinal unit conductance recorded regional average value of 1.168, while 1.20, 1.16, and 1.10 were recorded for granite, gneiss and migmatite, which suggests moderate vulnerability to contamination. The average values recorded for overburden thickness, hydraulic conductivity, transmissivity, transverse resistance, formation factor, coefficient of anisotropy, fracture contrast, and reflection coefficient are 22.5 m, 0.33 m/d, 5.56 m²/d, 4966 ohm-m², 2.42, 1.17, 15.3, and 0.66 respectively. The water table aquifer and the fractured basement are the major water bearing units in the area; while the geological units showed overlapping hydrogeologic properties. The obtained GWPIV ranged from 1.21 to 3.55 with regional average of 1.86, suggesting a moderate potential. Nevertheless, the southern part showed more propensity/yield than the northern area. The study showed the importance of geospatial mapping technique, involving fuzzy analytical hierarchical process, in groundwater evaluation, as it was able to solve and obtain different hydrogeological parameters, which were integrated to prioritize and define the area's groundwater prolificacy for the purpose of improving, expanding, and management of the existing water scheme in the study area.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":"8 4","pages":"Pages 319-344"},"PeriodicalIF":2.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X23000417/pdfft?md5=eed007e09a446b603897e8738e151065&pid=1-s2.0-S2451912X23000417-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138615204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}