Journal of Geosciences最新文献

{"title":"Ferraioloite from the Sítio do Castelo mine, Folgosinho (Guarda, Portugal), description and Raman spectroscopy","authors":"J. Tvrdý, J. Sejkora, P. Rosseel, Z. Dolníček","doi":"10.3190/jgeosci.326","DOIUrl":"https://doi.org/10.3190/jgeosci.326","url":null,"abstract":"A zinc phosphate corresponding to ferraioloite with low Mg and high Na cation contents in interlayer space was identified in samples from the Sítio do Castelo mine, Folgosinho (Guarda, Portugal). It occurs as sky-blue, pearly lustrous, radial or irregular aggregates up to 1 mm in size composed of very thin elongated flaky crystals. The mineral is monoclinic, space group I2/m, with unit-cell parameters refined from X-ray powder diffraction data: a = 25.417(7), b = 6.342(4), c =15.186(5) Å, β = 90.02(4)°, V = 2448.0(17) Å3. The chemical composition generally agrees with published data for ferraioloite, but differs significantly in elements present at sites assumed to be in the interlayer of the crystal structure. The corresponding empirical formula based on 8 (PO)4 and 4 (OH) groups pfu is (Mg0.16Na0.15Ca0.09K0.01)Σ0.41Mn4.22(Fe1.64 Fe1.15Al1.47)Σ4.26Zn3.87(PO4)8(OH)4(H2O)20. The Raman spectra and tentative assignment of observed bands are given. The most prominent bands are attributed to stretching and bending vibrations of phosphate tetrahedra and complex metal-centered polyhedra. Bands of O–H stretching vibrations are weak, and bending vibrations of water molecules were not observed. The origin of the mineral is related to in-situ supergene weathering of zwieselite–triplite and isokite–fluorapatite assemblages with admixtures of sphalerite.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42978488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal structure of undersubstituted Sb-rich vikingite Vik40, Ag2.85Pb12.35(Bi9.52Sb1.27)Σ=10.80S30: site population and comparison with structure of vikingite Vik50, Ag3.5Pb11.0Bi11.5S30","authors":"R. Pažout, M. Dušek","doi":"10.3190/jgeosci.329","DOIUrl":"https://doi.org/10.3190/jgeosci.329","url":null,"abstract":"Crystal structure of Sb-rich vikingite with lillianite substitution percentage L % below 50 % from Kutná Hora ore district, Czech Republic, was solved and refined from single-crystal diffraction data to determine the site populations of metal sites concerning a) the decreasing “lillianite“ substitution 2 Pb2+ = Ag+ + Bi; b) Sb content not known in vikingite from other localities throughout the world. Vikingite is monoclinic, C2/m, with a = 13.5394(10), b = 4.0992(3), c = 25.506(3) Å, β = 95.597(8)°, V = 1408.9(2) Å3, Z = 1, Dc = 7.0412 g/cm3. The structural formula derived from the refinement is Ag2.85Pb12.35(Bi9.52Sb1.27)Σ=10.80S30, corresponding to Vik40.0. The structure of vikingite is composed of thinner slabs (4L) of four octahedra Me2–Me1–Me1–Me2 and thicker slabs (7L) of seven octahedra Me4–Me5–Me6–Me7–Me6–Me5–Me4 separated by Pb atoms Me3 in trigonal prismatic coordination. The refinement showed differences between the structures of Vik40 and the previously published structure of Vik50. The drop of L % below 50 % shows most profoundly in the marginal octahedral site Me2 of the thinner 4L slabs, which becomes a Bi–Pb–Ag site with 28.6 % of silver next to 50 % of Bi and 21.4 % of Pb. The central Me1 site from 4L slabs which is almost a pure Bi site in Vik50 (0.97 Bi + 0.3 Ag) becomes a Bi-Pb site with minor Sb (0.54 Bi + 0.06 Sb + 0.40 Pb) in Vik40. The Sb for Bi substitution was found to take place in the semimarginal site Me5 (0.74 Bi + 0.26 Sb) in the thicker 7L slabs, which is a pure Bi site in Sb-free Vik50. Another important change against Vik50 occurs in central octahedral site Me6 (pure Pb site in Vik50), which becomes – despite the decrease in Bi content with decreasing L % – a Pb–Bi mix site. The correctness of the refined structural model was verified and the occupancies of mixed sites were fine-tuned employing charge distribution calculations in program ECoN21. In Vik40 weighted average bond lengths RAV of the marginal sites Me2 and Me4 and of the central site Me1 are significantly larger than in Vik50, reflecting the lower Ag content and the presence of Pb, while the Bi site Me5, which is partly substituted by Sb and the site Me6 with minor Bi at the expense of Pb exhibit adequately shortened RAV values.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41533842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Auerbakhite, MnTl2As2S5, a new thallium sulfosalt from the Vorontsovskoe gold deposit, Northern Urals, Russia","authors":"A. Kasatkin, J. Plášil, E. Makovicky, N. Chukanov, R. Škoda, A. Agakhanov, S. Stepanov, R. Palamarchuk","doi":"10.3190/JGEOSCI.321","DOIUrl":"https://doi.org/10.3190/JGEOSCI.321","url":null,"abstract":"1 Fersman Mineralogical Museum of Russian Academy of Sciences, Leninsky Prospekt 18–2, 119071 Moscow, Russia; anatoly.kasatkin@gmail.com 2 Institute of Physics, Academy of Sciences of the Czech Republic v.v.i, Na Slovance 1999/2, Prague 8, 182 21, Czech Republic 3 Department of Geoscience and Resource Management, University of Copenhagen, Østervoldgade 10, DK–1350, Copenhagen K, Denmark 4 Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow region, 142432 Russia 5 Department of Geological Sciences, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic 6 Institute of Geology and Geochemistry, UB RAS, Akademika Vonsovskogo 15, Yekaterinburg, 620016 Russia 7 South Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Institute of Mineralogy, Miass, Chelyabinsk oblast, 456317 Russia * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48147475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A geochemical study of gersdorffite from the Trepça Mineral Belt, Vardar Zone, Kosovo","authors":"Sławomir Mederski, Marcin Wojslaw, Stanislav Prsek, J. Majzlan, S. Kiefer, Burim Asllani","doi":"10.3190/JGEOSCI.322","DOIUrl":"https://doi.org/10.3190/JGEOSCI.322","url":null,"abstract":"This work presents a textural and chemical study of gersdorffite from numerous small occurrences of hydrothermal Pb–Zn + (Ni–As–Sb) mineralization from Trepça Mineral Belt (broad area of Stan Terg and Kizhnica–Hajvalia–Badovc ore field) hosted in hydrothermally altered serpentinites (listvenites). Mineral associations, textural relations and substitutional trends of gersdorffite recognized in Kizhnica, Mazhiq, Melenica, Vllahia and Selac are discussed based on microscopy and microprobe studies. The two types of paragenetic sequence with nickel mineralization are distinguished in studied localities: Ni–Fe–Co sulfides → Ni sulfarsenides and sulfantimonides (in Kizhnica–Badovc and Melenica) and Ni sulfarsenides → Ni–Fe arsenide and diarsenide → ± Ni sulfides (Vllahia and Selac). Various substitution trends in studied GUS are detected: Fe + Co/Ni (all localities, except Selac); As/Sb – gersdorffite–ullmannite series (Kizhnica, Mazhiq, Vllahia VLX) and As + Sb/S (Selac and Vllahia VL4). Based on As/S ratio, two different hydrothermal fluids were distinguished: narrow range and low As/S values (Kizhnica, Mazhiq, Melenica, Vllahia VLX), which suggest decreased As activity, mixing in the proximity of deposition site (Kizhnica, Mazhiq), broad range and high As/S values: increased As activity and disequilibrium crystallization (Selac, Vllahia VL4).","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42077512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specific spectroscopic features of yellow cuboid diamonds from placers in the north-eastern Siberian Platform","authors":"R. Mashkovtsev, M. Rakhmanova, D. Zedgenizov","doi":"10.3190/JGEOSCI.323","DOIUrl":"https://doi.org/10.3190/JGEOSCI.323","url":null,"abstract":"1 Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences, 3 Koptyug ave., Novosibirsk 630090, Russia; email: rim@igm.nsc.ru 2 Nikolaev Institute of Inorganic Chemistry Siberian Branch Russian Academy of Sciences, 3 Lavrentyev str., Novosibirsk 630090, Russia 3 Zavaritsky Institute of Geology and Geochemistry Ural Branch Russian Academy of Sciences, 15 Vonsovskogo str., Ekaterinburg, 620016, Russia * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46407763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis of silica-rich carbonatites from continental rift settings: a missing link between carbonatites and carbonated silicate melts?","authors":"L. Ackerman, V. Rapprich, L. Polák, T. Magna, V. McLemore, O. Pour, B. Cejkova","doi":"10.3190/JGEOSCI.320","DOIUrl":"https://doi.org/10.3190/JGEOSCI.320","url":null,"abstract":"1 Institute of Geology of the Czech Academy of Sciences of the Czech Republic, Rozvojová 269, 165 00 Prague 6, Czech Republic; ackerman@gli.cas.cz 2 Czech Geological Survey, Klárov 3, 118 21 Prague 1, Czech Republic 3 Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic 4 New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of Mining and Technology, 801 Leroy Pl, Socorro, USA * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42430961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dobšináite, Ca2Ca(AsO4)2·2H2O, a new member of the roselite group from Dobšiná (Slovak Republic)","authors":"J. Sejkora, M. Števko, R. Škoda, E. Viskova, J. Toman, Sebastián Hreus, J. Plášil, Z. Dolníček","doi":"10.3190/JGEOSCI.324","DOIUrl":"https://doi.org/10.3190/JGEOSCI.324","url":null,"abstract":"1 Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, 193 00 Prague 9, Czech Republic; jiri.sejkora@nm.cz 2 Earth Science Institute, Slovak Academy of Sciences, Dúbravská cesta 9, 840 05 Bratislava, Slovak Republic 3 Department of Geological Sciences, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic 4 Department of Mineralogy and Petrography, Moravian Museum, Zelný trh 6, 659 37 Brno, Czech Republic 5 Institute of Physics, Academy of Sciences of the Czech Republic v.v.i, Na Slovance 2, 182 21 Prague 8, Czech Republic * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41676130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Depth-to-basement study for the western Polish Outer Carpathians from three-dimensional joint inversion of gravity and magnetic data","authors":"Mateusz Mikołajczak, J. Barmuta, Malgorzata Ponikowska, S. Mazur, K. Starzec","doi":"10.3190/JGEOSCI.317","DOIUrl":"https://doi.org/10.3190/JGEOSCI.317","url":null,"abstract":"Results of a depth-to-basement study are presented for the westernmost Polish Outer Carpathians. The gravity data are inverted for the top of the Precambrian basement using horizons from 2–D gravity and magnetic forward models and well tops as input depth measurements. 2–D models, used in the study, are built upon depth converted seismic profiles. The results are visualized as an isobath map for the top of the Precambrian basement, complemented with the qualitative structural interpretation of gravity and magnetic anomaly maps. The outcome of 3–D joint inversion of the gravity data and depth measurements shows the Precambrian crystalline basement deepening southward from c. 1 to almost 7 km b. s. l. Consequently, an approximately 2 km thick wedge of autochthonous sediments, thickening southward, is embraced between the crystalline basement and a sole detachment of the Carpathian fold-and-thrust belt, imaged by seismic data. Since the modelled top of the crystalline basement is roughly parallel to the Moho, suggesting no extension-related thinning in Mesozoic, the autochthonous sediments are likely of pre-Permian age. A positive magnetic anomaly in the south of the study area is presumably associated with the presence of an elongated body of intermediate to mafic rocks in the basement of the Brunovistulian Terrane. These rocks may represent a relic of a Cadomian magmatic arc comparable to that existing in the Brno Massif of southern Moravia.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45819961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogy of the Rincón Blanco selenide occurrence, La Rioja, Argentina","authors":"M. F. Márquez-Zavalía, M. A. Galliski, P. Škácha, I. Macek, J. Sejkora, Z. Dolníček","doi":"10.3190/JGEOSCI.316","DOIUrl":"https://doi.org/10.3190/JGEOSCI.316","url":null,"abstract":"1 IANIGLA, CCT-Mendoza (CONICET), Avda. A. Ruiz Leal s/n, Parque San Martin, CC330, 5500 Mendoza, Argentina; mzavalia@mendoza-conicet.gov.ar 2 Mineralogía y Petrología, F.A.D., Universidad Nacional de Cuyo, Centro Universitario, 5502 Mendoza, Argentina 3 Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, 193 00 Prague 9, Czech Republic 4 Hornické Muzeum Příbram, Náměstí Hynka Kličky 293, 261 01 Příbram, Czech Republic * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"1 1","pages":"1-14"},"PeriodicalIF":1.4,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42089202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Krupičkaite, Cu6[AsO3(OH)]6·8H2O, a new copper arsenate mineral from Jáchymov (Czech Republic)","authors":"G. Steciuk, J. Sejkora, J. Čejka, J. Plášil, J. Hloušek","doi":"10.3190/JGEOSCI.318","DOIUrl":"https://doi.org/10.3190/JGEOSCI.318","url":null,"abstract":"Krupičkaite, ideally Cu6[AsO3(OH)]6·8H2O, is a new supergene mineral from the Rovnost I shaft in Jáchymov, Czech Republic. It forms aggregates of pale greenish-blue color and grows along with supergene minerals crystallizing on the strongly altered relics of massive tennantite, Bi-rich tennantite, galena, chalcopyrite, bornite, and chalcocite with disseminated uraninite in quartz. For a long time, krupičkaite has been left out due to its quite inconspicuous ap pearance that can be mistakenly referred to as geminite. At the ambient temperature, krupičkaite is monoclinic, a = 15.504(7) Å, b = 18.144(7) Å, c = 10.563(5) Å, β = 103.30(4)°, V = 2891.5(2) Å3, Z = 4, space group P21/m. Its structure has been solved and refined from 3D electron diffraction and further studied by Raman spectroscopy. The layered structure is built upon the alternation of two different copper-arsenate sheets stacked along b presenting a characteristic wave shape along the a–axis and separated by a thick interlayer with channels containing only H2O. The collapsed chains of copper polyhedra are connected the same way as in geminite through AsO4 tetrahedra. Krupičkaite joins the family of copper arsenate minerals with which it shares structural similarities at the level of the As-Cu layers with the lindackerite supergroup, slavkovite, or yvonite.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"1 1","pages":"37-50"},"PeriodicalIF":1.4,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45107335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}