Tonalites to granites of the Tynong Batholith, Lachlan Orogen, southeastern Australia as well as enclaves within them contain primary clinoand orthopyroxenes. These plutons produced very broad (2–10 km) contact aureoles that contain an anatectic zone within metagreywackes. The very broad contact aureoles can be related to the 3-D shapes of the plutons and we assume that the Cpx and Opx are remnants of higher temperature crystallization that were preserved due to water loss or low water content in the magma. Estimates of P and T based on x(Fe) values for coexisting cordierite and biotite in P–T pseudosections for a typical migmatitic hornfels, providing minimum temperature of pluton emplacement, indicate emplacement of the Toorongo tonalite at 4–10 km (1–3 kbar) and 680–750 °C. However, the isopleths of An content of plagioclase indicate depths of up to 14 km at 660–740 °C. We suggest that plagioclase was partially re-equilibrated during melt loss and post-emplacement decompression. Cathodoluminescence (CL) imaging shows that quartz both in the tonalites and hornfels is typically zoned from higher Ti contents in cores to lower in the margins, suggesting a response to falling temperature. Calculated temperatures for quartz crystallization using a Ti-in-quartz thermometer calibrated for 2.5 kbar gave a wide range of values between 900 and 500 °C. This suggests that although the granitoids contain two pyroxenes and have produced a broad contact aureole, they were not emplaced at temperatures as high as previously inferred.
{"title":"Was the Tynong Batholith, Lachlan Orogen, Australia, extremely hot? Application of pseudosection modelling and TitaniQ geothermometry","authors":"K. Regmi, P. Hasalová, I. Nicholls","doi":"10.3190/jgeosci.305","DOIUrl":"https://doi.org/10.3190/jgeosci.305","url":null,"abstract":"Tonalites to granites of the Tynong Batholith, Lachlan Orogen, southeastern Australia as well as enclaves within them contain primary clinoand orthopyroxenes. These plutons produced very broad (2–10 km) contact aureoles that contain an anatectic zone within metagreywackes. The very broad contact aureoles can be related to the 3-D shapes of the plutons and we assume that the Cpx and Opx are remnants of higher temperature crystallization that were preserved due to water loss or low water content in the magma. Estimates of P and T based on x(Fe) values for coexisting cordierite and biotite in P–T pseudosections for a typical migmatitic hornfels, providing minimum temperature of pluton emplacement, indicate emplacement of the Toorongo tonalite at 4–10 km (1–3 kbar) and 680–750 °C. However, the isopleths of An content of plagioclase indicate depths of up to 14 km at 660–740 °C. We suggest that plagioclase was partially re-equilibrated during melt loss and post-emplacement decompression. Cathodoluminescence (CL) imaging shows that quartz both in the tonalites and hornfels is typically zoned from higher Ti contents in cores to lower in the margins, suggesting a response to falling temperature. Calculated temperatures for quartz crystallization using a Ti-in-quartz thermometer calibrated for 2.5 kbar gave a wide range of values between 900 and 500 °C. This suggests that although the granitoids contain two pyroxenes and have produced a broad contact aureole, they were not emplaced at temperatures as high as previously inferred.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"121-138"},"PeriodicalIF":1.4,"publicationDate":"2020-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48777646","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}
A Microsoft® Visual Basic software, called WinGrt, has been developed to calculate and classify wet-chemical and electron-microprobe garnet supergroup mineral analyses. The program evaluates 33 approved species that belong to the tetragonal henritermierite and isometric bitikleite, schorlomite, garnet and berzeliite groups based on the Commission on New Minerals and Mineral Names (CNMMN) of the International Mineralogical Association (IMA–13) nomenclature scheme. WinGrt also evaluates thirty geothermometers using the Fe2+–Mg exchange reactions for garnet–biotite, garnet–clinopyroxene and garnet–orthopyroxene pairs within the application range of greenschist-, amphibolite-, granuliteand eclogite-facies metamorphic rocks. As naturally occurring garnet is potentially a useful provenance indicator, the program calculates end-member molecules from chemical compositions on the basis of different approaches and yields pyrope, almandine, spessartine, grossular, andradite and schorlomite phase on various ternary discrimination diagrams used in provenance studies. The ferric and ferrous iron contents from total FeO (wt. %) amount are estimated by stoichiometric constraints. The program allows the users to enter 30 input variables including Sample No, SiO2, TiO2, ZrO2, HfO2, Th2O, SnO2, Al2O3, Cr2O3, V2O3, Fe2O3, Mn2O3, Sc2O3, Y2O3 + REE2O3, FeO, MgO, MnO, ZnO, CaO, Na2O, Li2O, P2O5, V2O5, Sb2O5, As2O5, Nb2O5, UO3, Te2O3, F and H2O (wt. %). WinGrt also enables the user to enter the total REE2O3 (wt. %) as input values from La2O3 to Lu2O3 (wt. %) of garnet supergroup mineral analyses in program’s data edit section. WinGrt enables the user to type or load multiple garnet compositions in the data entry section, to edit and load Microsoft® Excel files in calculating, classifying and naming the garnet species, and to store all the calculated parameters in the Microsoft® Excel file for further evaluation.
{"title":"WinGrt, a Windows program for garnet supergroup minerals","authors":"F. Yavuz, D. Yildirim","doi":"10.3190/jgeosci.303","DOIUrl":"https://doi.org/10.3190/jgeosci.303","url":null,"abstract":"A Microsoft® Visual Basic software, called WinGrt, has been developed to calculate and classify wet-chemical and electron-microprobe garnet supergroup mineral analyses. The program evaluates 33 approved species that belong to the tetragonal henritermierite and isometric bitikleite, schorlomite, garnet and berzeliite groups based on the Commission on New Minerals and Mineral Names (CNMMN) of the International Mineralogical Association (IMA–13) nomenclature scheme. WinGrt also evaluates thirty geothermometers using the Fe2+–Mg exchange reactions for garnet–biotite, garnet–clinopyroxene and garnet–orthopyroxene pairs within the application range of greenschist-, amphibolite-, granuliteand eclogite-facies metamorphic rocks. As naturally occurring garnet is potentially a useful provenance indicator, the program calculates end-member molecules from chemical compositions on the basis of different approaches and yields pyrope, almandine, spessartine, grossular, andradite and schorlomite phase on various ternary discrimination diagrams used in provenance studies. The ferric and ferrous iron contents from total FeO (wt. %) amount are estimated by stoichiometric constraints. The program allows the users to enter 30 input variables including Sample No, SiO2, TiO2, ZrO2, HfO2, Th2O, SnO2, Al2O3, Cr2O3, V2O3, Fe2O3, Mn2O3, Sc2O3, Y2O3 + REE2O3, FeO, MgO, MnO, ZnO, CaO, Na2O, Li2O, P2O5, V2O5, Sb2O5, As2O5, Nb2O5, UO3, Te2O3, F and H2O (wt. %). WinGrt also enables the user to enter the total REE2O3 (wt. %) as input values from La2O3 to Lu2O3 (wt. %) of garnet supergroup mineral analyses in program’s data edit section. WinGrt enables the user to type or load multiple garnet compositions in the data entry section, to edit and load Microsoft® Excel files in calculating, classifying and naming the garnet species, and to store all the calculated parameters in the Microsoft® Excel file for further evaluation.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"71-95"},"PeriodicalIF":1.4,"publicationDate":"2020-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48462614","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}
J. Sejkora, E. Makovicky, T. Balić-Žunić, P. Berlepsch
The new mineral stangersite was found in the burning waste dump of abandoned Kateřina coal mine at Radvanice near Trutnov, northern Bohemia, Czech Republic. The new mineral occurs as well-formed, flattened, acicular crystals with a cross-section of 2–5 × 20–40 μm and up to 1 cm in length. They constitute random or fan-shaped clusters on rock fragments and on crumbly black ash in association with greenockite, herzenbergite, unnamed GeS 2 and GeAsS. Stangersite was also observed as irregular grains, up to 100 μm in size, in the multicomponent aggregates on which the above-described crystals grow. These aggregates are formed, beside stangersite, by minerals of Bi–Sb, Bi 2 S 3 –Sb 2 S 3 and Bi 2 S 3 –Bi 2 Se 3 solid solutions, Bi 3 S 2 , Bi-sulfo/seleno/tellurides, tellurium, unnamed PbGeS 3 , Cd 4 GeS 6 , GeAsS, GeS 2 , Sn 5 Sb 3 S 7 , greenockite, cadmoindite, herzenbergite, teallite and Sn- and/or Se-bearing galena. Stangersite formed under reducing conditions by direct crystallization from hot gasses (250–350 °C) containing Cl and F, at a depth of 30–60 cm under the surface of the (100) layers of Sn 2+ S 5 coordination pyramids and with interspaces filled by lone electron pairs of Sn 2+ and [001] chains of Ge 4+ S 4 coordination tetrahedra. The Raman spectrum of stangersite with tentative band assignments is given. We named the mineral after its chemical constituents: Sn ( stan num), Ge ( ger manium) and S ( s ulphur).
{"title":"Stangersite, a new tin germanium sulfide, from the Kateřina mine, Radvanice near Trutnov, Czech Republic","authors":"J. Sejkora, E. Makovicky, T. Balić-Žunić, P. Berlepsch","doi":"10.3190/jgeosci.306","DOIUrl":"https://doi.org/10.3190/jgeosci.306","url":null,"abstract":"The new mineral stangersite was found in the burning waste dump of abandoned Kateřina coal mine at Radvanice near Trutnov, northern Bohemia, Czech Republic. The new mineral occurs as well-formed, flattened, acicular crystals with a cross-section of 2–5 × 20–40 μm and up to 1 cm in length. They constitute random or fan-shaped clusters on rock fragments and on crumbly black ash in association with greenockite, herzenbergite, unnamed GeS 2 and GeAsS. Stangersite was also observed as irregular grains, up to 100 μm in size, in the multicomponent aggregates on which the above-described crystals grow. These aggregates are formed, beside stangersite, by minerals of Bi–Sb, Bi 2 S 3 –Sb 2 S 3 and Bi 2 S 3 –Bi 2 Se 3 solid solutions, Bi 3 S 2 , Bi-sulfo/seleno/tellurides, tellurium, unnamed PbGeS 3 , Cd 4 GeS 6 , GeAsS, GeS 2 , Sn 5 Sb 3 S 7 , greenockite, cadmoindite, herzenbergite, teallite and Sn- and/or Se-bearing galena. Stangersite formed under reducing conditions by direct crystallization from hot gasses (250–350 °C) containing Cl and F, at a depth of 30–60 cm under the surface of the (100) layers of Sn 2+ S 5 coordination pyramids and with interspaces filled by lone electron pairs of Sn 2+ and [001] chains of Ge 4+ S 4 coordination tetrahedra. The Raman spectrum of stangersite with tentative band assignments is given. We named the mineral after its chemical constituents: Sn ( stan num), Ge ( ger manium) and S ( s ulphur).","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46934918","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 word of the retiring Editor-in-Chief & A word of the newly-coming Editor-in-Chief: (Not such) significant changes in the editorial board","authors":"V. Janoušek, J. Plášil","doi":"10.3190/jgeosci.311","DOIUrl":"https://doi.org/10.3190/jgeosci.311","url":null,"abstract":"","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46748840","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}
1 Mining muzeum Příbram, Hynka Kličky place 293, Příbram VI, 261 01, Czech Republic 2 Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, Prague 9-Horní Počernice, 193 00, Czech Republic; jiri_sejkora@nm.cz 3 Institute of Physics ASCR, v.v.i., Na Slovance 1999/2, 182 21 Praha 8, Czech Republic 4 Institute for Geoscience and Natural Resources Managment, University of Copenhagen, Østervolgade 10, DK-1350, Copenhagen K, Denmark * Corresponding author
1捷克共和国Příbram矿业博物馆，Hynka Kličky place 293，Pýíbram VI，261 01 2捷克共和国国家博物馆矿物学和岩石学部，Circusová1740，布拉格9-HorníPočernice，193 00；jiri_sejkora@nm.cz3物理研究所ASCR，v.v.i.，Na Slovance 1999/2，182 21 Praha 8，捷克共和国4哥本哈根大学地球科学和自然资源管理研究所，丹麦哥本哈根K，Östervolgade 10，DK-1350
{"title":"Pošepnýite, a new Hg-rich member of the tetrahedrite group from Příbram, Czech Republic","authors":"P. Škácha, J. Sejkora, J. Plášil, E. Makovicky","doi":"10.3190/jgeosci.308","DOIUrl":"https://doi.org/10.3190/jgeosci.308","url":null,"abstract":"1 Mining muzeum Příbram, Hynka Kličky place 293, Příbram VI, 261 01, Czech Republic 2 Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, Prague 9-Horní Počernice, 193 00, Czech Republic; jiri_sejkora@nm.cz 3 Institute of Physics ASCR, v.v.i., Na Slovance 1999/2, 182 21 Praha 8, Czech Republic 4 Institute for Geoscience and Natural Resources Managment, University of Copenhagen, Østervolgade 10, DK-1350, Copenhagen K, Denmark * Corresponding author","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45454407","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}
Herein, we constrain the Ngomedzap–Akongo geodynamic evolution in the eastern part of the Nyong complex (NyC) in SW Cameroon that belongs to the Paleoproterozoic West Central African Fold Belt (WCAF) through petrostructural field observations, laboratory analyses, and 207Pb/206Pb zircon geochronology. It consists of magnetite bearing quartzite, metagranodiorite, metaanorthosite, metagabbro, and metasyenites that have recorded a polyphase D1–D3 deformation. D1, likely a pure shear-type, has been strongly overprinted by the D2 transpression flow regime that emplaced the Nyong tectonic nappe, transported top – to the East onto the Congo shield. This nappe is dissected by D3 blastomylonitic shear-zones. Both the D2 and D3 have controlled the actual geometry of the Nyong belt, later crosscut by D4 multiple brittle tectonic styles, likely post-orogenic. Zircon geochronology yielded 207Pb/206Pb zircon geochronology protolith Archean mean ages of 2764 ± 26 Ma (MSWD = 0.81) in metagranodiorite; 2816 ± 34 Ma (MSWD = 1.3) and 2789 ± 13 Ma (MSWD = 0.28) in metasyenites. These new data corroborate old ones and, together, document the Archean origin of the NyC as details of the Nyong fold-and-thrust belts that of WCAFB and South American homologous due to the colliding Congo-San Francisco shields associated with Eburnean/Trans Amazonian orogeny (~2100–2050 Ma).
{"title":"The petrostructural characteristics and 207Pb/206Pb zircon data from the Ngomedzap-Akongo area (Nyong complex, SW-Cameroon)","authors":"S. Owona, J. M. Ondoa, M. Tichomirowa, G. Ekodeck","doi":"10.3190/jgeosci.309","DOIUrl":"https://doi.org/10.3190/jgeosci.309","url":null,"abstract":"Herein, we constrain the Ngomedzap–Akongo geodynamic evolution in the eastern part of the Nyong complex (NyC) in SW Cameroon that belongs to the Paleoproterozoic West Central African Fold Belt (WCAF) through petrostructural field observations, laboratory analyses, and 207Pb/206Pb zircon geochronology. It consists of magnetite bearing quartzite, metagranodiorite, metaanorthosite, metagabbro, and metasyenites that have recorded a polyphase D1–D3 deformation. D1, likely a pure shear-type, has been strongly overprinted by the D2 transpression flow regime that emplaced the Nyong tectonic nappe, transported top – to the East onto the Congo shield. This nappe is dissected by D3 blastomylonitic shear-zones. Both the D2 and D3 have controlled the actual geometry of the Nyong belt, later crosscut by D4 multiple brittle tectonic styles, likely post-orogenic. Zircon geochronology yielded 207Pb/206Pb zircon geochronology protolith Archean mean ages of 2764 ± 26 Ma (MSWD = 0.81) in metagranodiorite; 2816 ± 34 Ma (MSWD = 1.3) and 2789 ± 13 Ma (MSWD = 0.28) in metasyenites. These new data corroborate old ones and, together, document the Archean origin of the NyC as details of the Nyong fold-and-thrust belts that of WCAFB and South American homologous due to the colliding Congo-San Francisco shields associated with Eburnean/Trans Amazonian orogeny (~2100–2050 Ma).","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"201-219"},"PeriodicalIF":1.4,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49149048","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}
A study of zincoberaunite from Krásno near Horní Slavkov (Czech Republic) provided new chemical and structural data of this rare member of the beraunite group. The studied material is monoclinic, space group C2/c, with a = 20.3440(19) Å, b = 5.1507(3) Å, c = 19.1361(15) Å, β = 93.568(8)°, V = 2001.3(3) Å3, Z = 4. Based on refined site occupancies and bond-valence considerations, the structural formula is (Zn0.81Al0.19)(OH)2(Fe0.61Al0.39)(OH)2(H2O)2(Fe1.52Al0.48)(H2O)2(Fe1.72Al0.28) (OH)(PO4)3.83(AsO4)0.17(H2O)2. Electron-microprobe analyses support the obtained results. However, keeping the same cation occupancy at the M2–M4 sites, the ratio of Al3+ to Me2+ at the M1 site requires the presence of divalent cations as follows: (Zn0.57Fe0.24Al0.19)Σ1.00(Fe3.85Al1.15)Σ5.00[(PO4)3.89(AsO4)0.10(SiO4)0.01]Σ4.00[(OH)4.59F0.24 O0.17]Σ5.00(OH2)4.00·2H2O. Individual prismatic zincoberaunite crystals exhibit a chemical zonation manifested by increasing Fe and decreasing Zn and Al contents from cores to rims. The mineral composition is close to the Zn–Al-rich members of the beraunite group known from the same locality, but in this case, dominant occupancy of Zn at the M1 site was confirmed. With its increased aluminium content, zincoberaunite from Krásno differs significantly from the holotype specimen described from Hagendorf South pegmatite in Germany. The most prominent Raman bands are in good agreement with data published for related members of the beraunite group. Structure refinement (R = 3.56 % for 1906 observed unique reflections) revealed three different types of OH or H2O, which play distinct role in structure bonding.
{"title":"New crystal-chemical data on zincoberaunite from Krásno near Horní Slavkov (Czech Republic)","authors":"J. Tvrdý, J. Plášil, R. Škoda","doi":"10.3190/jgeosci.296","DOIUrl":"https://doi.org/10.3190/jgeosci.296","url":null,"abstract":"A study of zincoberaunite from Krásno near Horní Slavkov (Czech Republic) provided new chemical and structural data of this rare member of the beraunite group. The studied material is monoclinic, space group C2/c, with a = 20.3440(19) Å, b = 5.1507(3) Å, c = 19.1361(15) Å, β = 93.568(8)°, V = 2001.3(3) Å3, Z = 4. Based on refined site occupancies and bond-valence considerations, the structural formula is (Zn0.81Al0.19)(OH)2(Fe0.61Al0.39)(OH)2(H2O)2(Fe1.52Al0.48)(H2O)2(Fe1.72Al0.28) (OH)(PO4)3.83(AsO4)0.17(H2O)2. Electron-microprobe analyses support the obtained results. However, keeping the same cation occupancy at the M2–M4 sites, the ratio of Al3+ to Me2+ at the M1 site requires the presence of divalent cations as follows: (Zn0.57Fe0.24Al0.19)Σ1.00(Fe3.85Al1.15)Σ5.00[(PO4)3.89(AsO4)0.10(SiO4)0.01]Σ4.00[(OH)4.59F0.24 O0.17]Σ5.00(OH2)4.00·2H2O. Individual prismatic zincoberaunite crystals exhibit a chemical zonation manifested by increasing Fe and decreasing Zn and Al contents from cores to rims. The mineral composition is close to the Zn–Al-rich members of the beraunite group known from the same locality, but in this case, dominant occupancy of Zn at the M1 site was confirmed. With its increased aluminium content, zincoberaunite from Krásno differs significantly from the holotype specimen described from Hagendorf South pegmatite in Germany. The most prominent Raman bands are in good agreement with data published for related members of the beraunite group. Structure refinement (R = 3.56 % for 1906 observed unique reflections) revealed three different types of OH or H2O, which play distinct role in structure bonding.","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"45-57"},"PeriodicalIF":1.4,"publicationDate":"2020-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49545909","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":"Activation energy of annealed, partially metamict davidite by 57Fe Mössbauer spectroscopy","authors":"D. Malczewski, A. Grabias, M. Dziurowicz","doi":"10.3190/jgeosci.298","DOIUrl":"https://doi.org/10.3190/jgeosci.298","url":null,"abstract":"","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"37-44"},"PeriodicalIF":1.4,"publicationDate":"2020-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41515981","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}
Calcurmolite is a rare supergene U mineral formed during the alteration–hydration weathering of uraninite and hypogene Mo minerals; its structure has remained unsolved owing to a lack of crystal material suitable for conventional structure analysis. Here, single-crystal precession electron-diffraction tomography shows the calcurmolite (Rabejac, France) structure to be modulated; it is triclinic, crystallizing in the super-space group P1(α00)0, with a = 3.938 Å, b = 11.26 Å, c = 14.195 Å, α = 84.4°, β = 112.5°, γ = 133.95° and has a modulation vector q = 0.4 a*. Due to the poor quality of diffraction data, only a kinematical refinement was undertaken, although final results were reasonable: Robs/Rall = 0.3825/0.3834 for 3953/17442 observed/all reflections. The structure of calcurmolite is based upon the infinite uranyl–molybdate sheets with baumoite topology (U : Mo ratio = 1.5) and an interlayer of 6-coordinated Ca2+ cations with interstitial H2O (ligands are apical uranyl O atoms and molecular H2O). Adjacent sheets are linked via Ca–O, as well as H-bonds. The structure formula, based on assumed occupancies in the supercell 5a × b × c, is Ca[(UO2)3 (MoO4)2(OH)4](H2O)~5.0 (for Z = 4).
{"title":"Crystal structure of the uranyl-molybdate mineral calcurmolite Ca[(UO2)3(MoO4)2(OH)4](H2O)˜5.0: insights from a precession electron-diffraction tomography study","authors":"G. Steciuk, R. Škoda, J. Rohlíček, J. Plášil","doi":"10.3190/jgeosci.297","DOIUrl":"https://doi.org/10.3190/jgeosci.297","url":null,"abstract":"Calcurmolite is a rare supergene U mineral formed during the alteration–hydration weathering of uraninite and hypogene Mo minerals; its structure has remained unsolved owing to a lack of crystal material suitable for conventional structure analysis. Here, single-crystal precession electron-diffraction tomography shows the calcurmolite (Rabejac, France) structure to be modulated; it is triclinic, crystallizing in the super-space group P1(α00)0, with a = 3.938 Å, b = 11.26 Å, c = 14.195 Å, α = 84.4°, β = 112.5°, γ = 133.95° and has a modulation vector q = 0.4 a*. Due to the poor quality of diffraction data, only a kinematical refinement was undertaken, although final results were reasonable: Robs/Rall = 0.3825/0.3834 for 3953/17442 observed/all reflections. The structure of calcurmolite is based upon the infinite uranyl–molybdate sheets with baumoite topology (U : Mo ratio = 1.5) and an interlayer of 6-coordinated Ca2+ cations with interstitial H2O (ligands are apical uranyl O atoms and molecular H2O). Adjacent sheets are linked via Ca–O, as well as H-bonds. The structure formula, based on assumed occupancies in the supercell 5a × b × c, is Ca[(UO2)3 (MoO4)2(OH)4](H2O)~5.0 (for Z = 4).","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"15-25"},"PeriodicalIF":1.4,"publicationDate":"2020-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45905087","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}
Spectroscopy methods provide valuable information about the local structure of minerals, since they do not depend on long-range periodicity (they are sensitive to defects or substitutions and vice versa), and, therefore represent great complementary techniques to diffraction methods that are used to analyze periodic (global) structures of minerals. Spectroscopy techniques have been successfully applied to the minerals during past decades, namely due to still-growing possibilities connected with the evolution of the instrumentation and data analysis. Following the European Spectroscopic Conferences in Rome (1988), Berlin (1995), Kiev (1996), Paris (2001), Vienna (2004), Stockholm (2007), Potsdam (2011) and Rome (2015), the 9th European Conference on Mineralogy and Spectroscopy (ECMS 2019) took place at Břevnov Monastery, Prague, Czech Republic on September 10–13, 2019. The conference brought together 111 participants from 20 countries. One hundred two oral and poster contributions were presented during three days. Among these contributions, six invited keynote-talks were presented by Peter C. Burns (University of Notre Dame, USA), Janice Bishop (SETI Institute, USA), Sergey V. Krivovichev (St. Petersburg State University, Russia), Anna Vymazalová (Czech Geological Survey, Czechia), Jural Majzlan (Friedrich Schiller Universität, Germany) and Sergey S. Lobanov (GFZ German Research Center for Geosciences, Germany). About one third of the delegates were students, who had the opportunity to present their work to broad international audience. Two workshops focused on gemstone deposits and training in crystallographic com-
光谱学方法提供了有关矿物局部结构的有价值的信息，因为它们不依赖于长期周期性(它们对缺陷或取代敏感，反之亦然)，因此是用于分析矿物周期性(整体)结构的衍射方法的重要补充技术。光谱学技术在过去几十年中已成功地应用于矿物，这是由于仪器和数据分析的发展所带来的可能性不断增加。继罗马(1988年)、柏林(1995年)、基辅(1996年)、巴黎(2001年)、维也纳(2004年)、斯德哥尔摩(2007年)、波茨坦(2011年)和罗马(2015年)的欧洲光谱学会议之后，第九届欧洲矿物学和光谱学会议(ECMS 2019)于2019年9月10日至13日在捷克共和国布拉格Břevnov修道院举行。会议汇集了来自20个国家的111名与会者。三天内提交了120份口头和海报稿件。其中，Peter C. Burns(美国圣母大学)，Janice Bishop(美国SETI研究所)，Sergey V. Krivovichev(俄罗斯圣彼得堡国立大学)，Anna vymazalov(捷克地质调查局，捷克)，Jural Majzlan (Friedrich Schiller Universität，德国)和Sergey S. Lobanov(德国GFZ德国地球科学研究中心)做了6次特邀主题演讲。大约三分之一的代表是学生，他们有机会向广泛的国际观众介绍他们的作品。两个讲习班集中于宝石矿床和晶体学培训
{"title":"Foreword to the special issue arising from the 9th European Conference on Mineralogy and Spectroscopy","authors":"F. Laufek, J. Plášil, J. Cempírek, R. Škoda","doi":"10.3190/jgeosci.302","DOIUrl":"https://doi.org/10.3190/jgeosci.302","url":null,"abstract":"Spectroscopy methods provide valuable information about the local structure of minerals, since they do not depend on long-range periodicity (they are sensitive to defects or substitutions and vice versa), and, therefore represent great complementary techniques to diffraction methods that are used to analyze periodic (global) structures of minerals. Spectroscopy techniques have been successfully applied to the minerals during past decades, namely due to still-growing possibilities connected with the evolution of the instrumentation and data analysis. Following the European Spectroscopic Conferences in Rome (1988), Berlin (1995), Kiev (1996), Paris (2001), Vienna (2004), Stockholm (2007), Potsdam (2011) and Rome (2015), the 9th European Conference on Mineralogy and Spectroscopy (ECMS 2019) took place at Břevnov Monastery, Prague, Czech Republic on September 10–13, 2019. The conference brought together 111 participants from 20 countries. One hundred two oral and poster contributions were presented during three days. Among these contributions, six invited keynote-talks were presented by Peter C. Burns (University of Notre Dame, USA), Janice Bishop (SETI Institute, USA), Sergey V. Krivovichev (St. Petersburg State University, Russia), Anna Vymazalová (Czech Geological Survey, Czechia), Jural Majzlan (Friedrich Schiller Universität, Germany) and Sergey S. Lobanov (GFZ German Research Center for Geosciences, Germany). About one third of the delegates were students, who had the opportunity to present their work to broad international audience. Two workshops focused on gemstone deposits and training in crystallographic com-","PeriodicalId":15957,"journal":{"name":"Journal of Geosciences","volume":"65 1","pages":"1-2"},"PeriodicalIF":1.4,"publicationDate":"2020-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47210758","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}
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