Paulina Pyka, A. Gawęda, K. Szopa, A. Müller, M. Sikorska
Abstract In the Tatra Mountains (Slovakia) metamorphic complex, kyanite-quartz segregations with biotite-rich selvage occur in mylonitized mica schists. In this paper, the problem of fluid flow and aluminium mobility during the uplift of the crystalline massif, and the position of the segregations in the history of Western Tatra metamorphic complex, is adressed. The reaction Alm + Rt ➔ Ilm + Ky + Qtz is considered to be the result of a pressure drop from above to below 9 kbar. Ti-in-biotite geothermometry shows the temperature range to be 579-639°C that is related to heating and decompression associated with granite intrusion. Major-element mass-balance calculations show that Al remained stable in the selvage + segregation system whereas other elements (e.g. Cr, HFSE) were mobilized. The kyanite-quartz segregations formed from local fluids generated during dehydration of the metapelitic rocks during uplift. The main mechanism was likely diffusion-driven mass-transfer into extension-related cracks.
在斯洛伐克塔特拉山变质杂岩中，糜棱岩化云母片岩中出现了富含黑云母的蓝晶石-石英分选。本文讨论了结晶体隆升过程中的流体流动和铝的迁移问题，以及西太特拉变质杂岩中分离作用的历史地位。反应Alm + Rt《Ilm + Ky + Qtz》被认为是压力从9千巴以上降至9千巴以下的结果。黑云母中钛的温度范围为579 ~ 639℃，与花岗岩侵入相关的升温减压有关。主元素质量平衡计算表明，Al在织边+偏析体系中保持稳定，而其他元素(如Cr、HFSE)被调动。蓝晶石-石英嵌合体是由变质长晶石在隆升过程中脱水产生的局部流体形成的。主要机制可能是扩散驱动的传质进入与伸展相关的裂纹。
{"title":"Petrogenesis of kyanite-quartz segregations in mica schists of the Western Tatra Mountains (Slovakia)","authors":"Paulina Pyka, A. Gawęda, K. Szopa, A. Müller, M. Sikorska","doi":"10.1515/mipo-2015-0007","DOIUrl":"https://doi.org/10.1515/mipo-2015-0007","url":null,"abstract":"Abstract In the Tatra Mountains (Slovakia) metamorphic complex, kyanite-quartz segregations with biotite-rich selvage occur in mylonitized mica schists. In this paper, the problem of fluid flow and aluminium mobility during the uplift of the crystalline massif, and the position of the segregations in the history of Western Tatra metamorphic complex, is adressed. The reaction Alm + Rt ➔ Ilm + Ky + Qtz is considered to be the result of a pressure drop from above to below 9 kbar. Ti-in-biotite geothermometry shows the temperature range to be 579-639°C that is related to heating and decompression associated with granite intrusion. Major-element mass-balance calculations show that Al remained stable in the selvage + segregation system whereas other elements (e.g. Cr, HFSE) were mobilized. The kyanite-quartz segregations formed from local fluids generated during dehydration of the metapelitic rocks during uplift. The main mechanism was likely diffusion-driven mass-transfer into extension-related cracks.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"65 1","pages":"120 - 99"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76048111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The Ukrainian Shield (USh) is a typical province of Proterozoic alkaline magmatism where about 50 massifs and occurrences of alkaline rocks and carbonatites have been found. In spite of the wide distribution of Devonian basaltic- and alkaline magmatic rocks in the Dnieper-Donetsk depression adjacent to the USh, and in a marginal zone of the USh adjacent to folded Donbass, only alkaline rocks of Proterozoic age (1.8-2.1 Ga) that have been identified in the central interior of the USh. Some discrete bodies of 2.8 Ga subalkaline rocks also occur in Bogdanivka massif (Azov area). Occurrences of both Proterozoic (prevailing) and Phanerozoic (Devonian) alkaline rocks and kimberlites are only found in the eastern part of the USh (Azov area). Kimberlites in the central part of the Ukrainian Shield (Kirovograd region) are also of Proterozoic age (ca 1.8 Ga). It is this predominance of Precambrian rocks that makes the USh so different from other alkaline provinces where Phanerozoic alkaline rocks and kimberlites commonly prevail over Precambrian rocks. The lack of Phanerozoic alkaline magmatism on USh is poorly understood. Two main complexes of alkaline rocks - alkaline-ultrabasic (carbonatitic) and gabbro- syenitic - are distinguished in the USh. There are also rare occurrences of rock types such as alkaline- and alkaline-feldspar granites that may represent one separate alkaline-granite complex. Alkaline rocks present in the Eastern (Azov) province and in the Western province display essentially different geochemical character. Those of the Eastern province show characteristics typical of alkaline-ultrabasic rocks (e.g. high contents of incompatible rare elementssuch as Nb, REE, Zr, Y, Sr, whereas those in the Western province are characterized by low contents of Nb and Zr, and REE in some cases. This fact is interpreted as reflecting different geodynamic conditions of their origin. The Eastern rocks were formed in rift settings, the Western rocks in crustal compressional settings (collision, subduction). Various mineral deposits of phosphorus (apatite), niobium, REE, yttrium and zirconium, including unusually rich ores of REE, Y and Zr (Azov and Yastrybetsky) are associated with the alkaline rocks and carbonatites of the USh.
{"title":"Alkaline rocks of the Ukrainian Shield: Some mineralogical, petrological and geochemical features","authors":"A. N. Ponomarenko, S. Kryvdik, A. Grinchenko","doi":"10.2478/mipo-2013-0008","DOIUrl":"https://doi.org/10.2478/mipo-2013-0008","url":null,"abstract":"Abstract The Ukrainian Shield (USh) is a typical province of Proterozoic alkaline magmatism where about 50 massifs and occurrences of alkaline rocks and carbonatites have been found. In spite of the wide distribution of Devonian basaltic- and alkaline magmatic rocks in the Dnieper-Donetsk depression adjacent to the USh, and in a marginal zone of the USh adjacent to folded Donbass, only alkaline rocks of Proterozoic age (1.8-2.1 Ga) that have been identified in the central interior of the USh. Some discrete bodies of 2.8 Ga subalkaline rocks also occur in Bogdanivka massif (Azov area). Occurrences of both Proterozoic (prevailing) and Phanerozoic (Devonian) alkaline rocks and kimberlites are only found in the eastern part of the USh (Azov area). Kimberlites in the central part of the Ukrainian Shield (Kirovograd region) are also of Proterozoic age (ca 1.8 Ga). It is this predominance of Precambrian rocks that makes the USh so different from other alkaline provinces where Phanerozoic alkaline rocks and kimberlites commonly prevail over Precambrian rocks. The lack of Phanerozoic alkaline magmatism on USh is poorly understood. Two main complexes of alkaline rocks - alkaline-ultrabasic (carbonatitic) and gabbro- syenitic - are distinguished in the USh. There are also rare occurrences of rock types such as alkaline- and alkaline-feldspar granites that may represent one separate alkaline-granite complex. Alkaline rocks present in the Eastern (Azov) province and in the Western province display essentially different geochemical character. Those of the Eastern province show characteristics typical of alkaline-ultrabasic rocks (e.g. high contents of incompatible rare elementssuch as Nb, REE, Zr, Y, Sr, whereas those in the Western province are characterized by low contents of Nb and Zr, and REE in some cases. This fact is interpreted as reflecting different geodynamic conditions of their origin. The Eastern rocks were formed in rift settings, the Western rocks in crustal compressional settings (collision, subduction). Various mineral deposits of phosphorus (apatite), niobium, REE, yttrium and zirconium, including unusually rich ores of REE, Y and Zr (Azov and Yastrybetsky) are associated with the alkaline rocks and carbonatites of the USh.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"14 1","pages":"115 - 124"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80933943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Voznyak, D. Chernysh, V. Melnikov, S. S. Ostapenko
Abstract Baddeleyite as inclusions in zircon crystals is described for the first time from the ore zone of the Azov zirconium-rare-earth deposit in the Volodarsky (Pivdennokalchytsky) syenite Massif in the Ukrainian Shield. The main admixture in the zircon containing baddeleyite is hafnium (0.68 wt%). The baddeleyite occurs in a substance that fills cracks and that probably corresponds to glass. The chemical compositions of four baddeleyite segregations, and of the hosting glass, are presented. The baddeleyite formed as a result of interaction between zircon and silicate melt with a low SiO2 content. The silicate melt formed under the influence of highthermobaric CO2-fluid flows on the rock.
{"title":"Baddeleyite segregations in zircon of the Azov zirconium-rare-earth deposit (Ukrainian Shield)","authors":"D. Voznyak, D. Chernysh, V. Melnikov, S. S. Ostapenko","doi":"10.2478/mipo-2013-0009","DOIUrl":"https://doi.org/10.2478/mipo-2013-0009","url":null,"abstract":"Abstract Baddeleyite as inclusions in zircon crystals is described for the first time from the ore zone of the Azov zirconium-rare-earth deposit in the Volodarsky (Pivdennokalchytsky) syenite Massif in the Ukrainian Shield. The main admixture in the zircon containing baddeleyite is hafnium (0.68 wt%). The baddeleyite occurs in a substance that fills cracks and that probably corresponds to glass. The chemical compositions of four baddeleyite segregations, and of the hosting glass, are presented. The baddeleyite formed as a result of interaction between zircon and silicate melt with a low SiO2 content. The silicate melt formed under the influence of highthermobaric CO2-fluid flows on the rock.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"53 1","pages":"125 - 131"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91388619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Andersen, M. Erambert, A. O. Larsen, R. Selbekk
Abstract Agpaitic nepheline syenites have complex, Na-Ca-Zr-Ti minerals as the main hosts for zirconium and titanium, rather than zircon and titanite, which are characteristic for miaskitic rocks. The transition from a miaskitic to an agpaitic crystallization regime in silica-undersaturated magma has traditionally been related to increasing peralkalinity of the magma, but halogen and water contents are also important parameters. The Larvik Plutonic Complex (LPC) in the Permian Oslo Rift, Norway consists of intrusions of hypersolvus monzonite (larvikite), nepheline monzonite (lardalite) and nepheline syenite. Pegmatites ranging in composition from miaskitic syenite with or without nepheline to mildly agpaitic nepheline syenite are the latest products of magmatic differentiation in the complex. The pegmatites can be grouped in (at least) four distinct suites from their magmatic Ti and Zr silicate mineral assemblages. Semiquantitative petrogenetic grids for pegmatites in log aNa2SiO5 - log aH2O - log aHF space can be constructed using information on the composition and distribution of minerals in the pegmatites, including the Zr-rich minerals zircon, parakeldyshite, eudialyte, låvenite, wöhlerite, rosenbuschite, hiortdahlite and catapleiite, and the Ti-dominated minerals aenigmatite, zirconolite (polymignite), astrophyllite, lorenzenite, titanite, mosandrite and rinkite. The chemographic analysis indicates that although increasing peralkalinity of the residual magma (given by the activity of the Na2Si2O5 or Nds component) is an important driving force for the miaskitic to agpaitic transition, water, fluoride (HF) and chloride (HCl) activity controls the actual mineral assemblages forming during crystallization of the residual magmas. The most distinctive mineral in the miaskitic pegmatites is zirconolite. At low fluoride activity, parakeldyshite, lorenzenite and wöhlerite are stable in mildly agpaitic systems. High fluorine (or HF) activity favours minerals such as låvenite, hiortdahlite,rosenbuschite and rinkite, and elevated water activity mosandrite and catapleiite. Astrophyllite and aenigmatite are stable over large ranges of Nds activity, at intermediate and low water activities, respectively.
{"title":"Petrology of nepheline syenite pegmatites in the Oslo Rift, Norway: Zr and Ti mineral assemblages in miaskitic and agpaitic pegmatites in the Larvik Plutonic Complex","authors":"T. Andersen, M. Erambert, A. O. Larsen, R. Selbekk","doi":"10.2478/mipo-2013-0007","DOIUrl":"https://doi.org/10.2478/mipo-2013-0007","url":null,"abstract":"Abstract Agpaitic nepheline syenites have complex, Na-Ca-Zr-Ti minerals as the main hosts for zirconium and titanium, rather than zircon and titanite, which are characteristic for miaskitic rocks. The transition from a miaskitic to an agpaitic crystallization regime in silica-undersaturated magma has traditionally been related to increasing peralkalinity of the magma, but halogen and water contents are also important parameters. The Larvik Plutonic Complex (LPC) in the Permian Oslo Rift, Norway consists of intrusions of hypersolvus monzonite (larvikite), nepheline monzonite (lardalite) and nepheline syenite. Pegmatites ranging in composition from miaskitic syenite with or without nepheline to mildly agpaitic nepheline syenite are the latest products of magmatic differentiation in the complex. The pegmatites can be grouped in (at least) four distinct suites from their magmatic Ti and Zr silicate mineral assemblages. Semiquantitative petrogenetic grids for pegmatites in log aNa2SiO5 - log aH2O - log aHF space can be constructed using information on the composition and distribution of minerals in the pegmatites, including the Zr-rich minerals zircon, parakeldyshite, eudialyte, låvenite, wöhlerite, rosenbuschite, hiortdahlite and catapleiite, and the Ti-dominated minerals aenigmatite, zirconolite (polymignite), astrophyllite, lorenzenite, titanite, mosandrite and rinkite. The chemographic analysis indicates that although increasing peralkalinity of the residual magma (given by the activity of the Na2Si2O5 or Nds component) is an important driving force for the miaskitic to agpaitic transition, water, fluoride (HF) and chloride (HCl) activity controls the actual mineral assemblages forming during crystallization of the residual magmas. The most distinctive mineral in the miaskitic pegmatites is zirconolite. At low fluoride activity, parakeldyshite, lorenzenite and wöhlerite are stable in mildly agpaitic systems. High fluorine (or HF) activity favours minerals such as låvenite, hiortdahlite,rosenbuschite and rinkite, and elevated water activity mosandrite and catapleiite. Astrophyllite and aenigmatite are stable over large ranges of Nds activity, at intermediate and low water activities, respectively.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"55 1","pages":"61 - 98"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80208725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Chevkinite-group minerals are widespread in a very wide range of igneous and metamorphic parageneses, forming important components of accessory mineral assemblages. Their presence in a rock may be difficult to establish by standard optical techniques, which has contributed to their importance being underestimated; a combination of SEM and EMPA is recommended here. Currently, there are eleven IMAapproved members of the group but undoubtedly several more will be described in the near future. There is considerable compositional variation in the group, which can be expressed as: REE + M2+C + M3+C = Ca2+ A + Sr + Ti4+C + Zr4+C where A and C are structural sites. Chevkinite-group minerals strongly fractionate geochemically coherent pairs, such as LREE-HREE, Nb-Ta, Zr-Hf and Th-U, and thus play a critical role in geochemical modelling.
菱铁矿群矿物广泛分布于火成岩和变质共生岩中，是副矿物组合的重要组成部分。它们在岩石中的存在可能很难用标准的光学技术确定，这导致了它们的重要性被低估;这里推荐SEM和EMPA的结合。目前，有11名ima认可的成员，但毫无疑问，在不久的将来会有更多的成员被描述。组内成分变化较大，可以表示为:REE + M2+C + M3+C = Ca2+ A + Sr + Ti4+C + Zr4+C，其中A和C为结构位点。chevkinite族矿物具有强烈的分馏作用，可形成LREE-HREE、Nb-Ta、Zr-Hf和Th-U等地球化学相干对，在地球化学模拟中发挥重要作用。
{"title":"The chevkinite group: underestimated accessory phases from a wide range of parageneses","authors":"B. Bagiński, R. Macdonald","doi":"10.2478/mipo-2013-0006","DOIUrl":"https://doi.org/10.2478/mipo-2013-0006","url":null,"abstract":"Abstract Chevkinite-group minerals are widespread in a very wide range of igneous and metamorphic parageneses, forming important components of accessory mineral assemblages. Their presence in a rock may be difficult to establish by standard optical techniques, which has contributed to their importance being underestimated; a combination of SEM and EMPA is recommended here. Currently, there are eleven IMAapproved members of the group but undoubtedly several more will be described in the near future. There is considerable compositional variation in the group, which can be expressed as: REE + M2+C + M3+C = Ca2+ A + Sr + Ti4+C + Zr4+C where A and C are structural sites. Chevkinite-group minerals strongly fractionate geochemically coherent pairs, such as LREE-HREE, Nb-Ta, Zr-Hf and Th-U, and thus play a critical role in geochemical modelling.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"6 1","pages":"114 - 99"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78414182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Large crystals of kyanite (<15 cm in size) occur in quartz segregations in Paleozoic gneissses on Baranec Mt., Western Tatra Mountains, northern Slovakia. Blue kyanite crystals coexist with quartz and plagioclase. The kyanite contains inclusions of apatite, monazite. gamet, rutile and biotite and overgrowths of retrograde sillimanite. muscovite and biotite. The kyanite crystals are the largest found up to now in the Tatra crystalline massif or in the other Western Carpathians crystalline cores. Kyanite. with the co-existing mineral assemblage, is indicative of a HP stage duiing Hercynian metamorphism of the Western Tatra Mountains.
{"title":"Megacrysts of kyanite from Baranec Mt., Western Tatra Mountains, Slovakia","authors":"Paulina Pyka, K. Szopa, A. Gawęda","doi":"10.2478/mipo-2013-0003","DOIUrl":"https://doi.org/10.2478/mipo-2013-0003","url":null,"abstract":"Abstract Large crystals of kyanite (<15 cm in size) occur in quartz segregations in Paleozoic gneissses on Baranec Mt., Western Tatra Mountains, northern Slovakia. Blue kyanite crystals coexist with quartz and plagioclase. The kyanite contains inclusions of apatite, monazite. gamet, rutile and biotite and overgrowths of retrograde sillimanite. muscovite and biotite. The kyanite crystals are the largest found up to now in the Tatra crystalline massif or in the other Western Carpathians crystalline cores. Kyanite. with the co-existing mineral assemblage, is indicative of a HP stage duiing Hercynian metamorphism of the Western Tatra Mountains.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"1 1","pages":"31 - 37"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82984657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Olivine basalts from southern Egypt were studied by 57Fe Mössbauer spectroscopy at 297 and 77 K, and by optical microscopy and X-ray diffraction. The 57Fe Mössbauer spectra show three-magnetic sextets, three doublets of ferrous (Fe2+), and a weak ferric (Fe3+) doublet that is attributable to a nanophase oxide (npOx). The magnetic sextets relate to titanomagnetite and the Fe2+ doublets to olivine, pyroxene, and ulvöspinel. Variations in the hyperfine parameters of the various Fe components are attributed to changes in the local crystal chemistry. The intensity of oxidation (Fe3+/ΣFe) in the rocks varies from 20-27% with the oxidized iron largely residing in the titanomagnetite.
{"title":"Mössbauer study of Fe phases in terrestrial olivine basalts from southern Egypt","authors":"K. Hassan, J. Dekan","doi":"10.2478/mipo-2013-0001","DOIUrl":"https://doi.org/10.2478/mipo-2013-0001","url":null,"abstract":"Abstract Olivine basalts from southern Egypt were studied by 57Fe Mössbauer spectroscopy at 297 and 77 K, and by optical microscopy and X-ray diffraction. The 57Fe Mössbauer spectra show three-magnetic sextets, three doublets of ferrous (Fe2+), and a weak ferric (Fe3+) doublet that is attributable to a nanophase oxide (npOx). The magnetic sextets relate to titanomagnetite and the Fe2+ doublets to olivine, pyroxene, and ulvöspinel. Variations in the hyperfine parameters of the various Fe components are attributed to changes in the local crystal chemistry. The intensity of oxidation (Fe3+/ΣFe) in the rocks varies from 20-27% with the oxidized iron largely residing in the titanomagnetite.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"7 1","pages":"12 - 3"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75686121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract 57Fe Mössbauer spectroscopy - a versatile technique involving the recoil-free, resonant absorption and emission of nuclear gamma (γ) rays by the iron-57 isotope in natural iron in solids - has been used to provide quantitative information about the mineral host, occupation sites and oxidation states of iron atoms in geological samples. This technique has been applied to the bulk chemistry of a barren soil (Soil A) derived from an aluminous-type granite and another barren soil (Soil B) derived from a sodic-type granite located ~ 100 kilometers apart in the Nubian Deseit in the currently hyper arid south-west of Egypt and which exhibit distinct chemical and mineral differences. The analyses indicate different mineral hosts for the iron in these samples, namely, vermiculite-chlorite plus some hematite in Soil A and hematite and goethite plus minor aegirines in Soil B. Each soil has distinct intensities of oxidized iron (89% for Soil A and 100% for Soil B) and these differences reflect changes in soil sources and processes.
{"title":"Characterization of barren, granitic soils from the Nubian Desert (SW Egypt) by 57Fe Mössbauer spectroscopy","authors":"K. Hassan, H. P. Gunnlaugsson","doi":"10.2478/mipo-2013-0004","DOIUrl":"https://doi.org/10.2478/mipo-2013-0004","url":null,"abstract":"Abstract 57Fe Mössbauer spectroscopy - a versatile technique involving the recoil-free, resonant absorption and emission of nuclear gamma (γ) rays by the iron-57 isotope in natural iron in solids - has been used to provide quantitative information about the mineral host, occupation sites and oxidation states of iron atoms in geological samples. This technique has been applied to the bulk chemistry of a barren soil (Soil A) derived from an aluminous-type granite and another barren soil (Soil B) derived from a sodic-type granite located ~ 100 kilometers apart in the Nubian Deseit in the currently hyper arid south-west of Egypt and which exhibit distinct chemical and mineral differences. The analyses indicate different mineral hosts for the iron in these samples, namely, vermiculite-chlorite plus some hematite in Soil A and hematite and goethite plus minor aegirines in Soil B. Each soil has distinct intensities of oxidized iron (89% for Soil A and 100% for Soil B) and these differences reflect changes in soil sources and processes.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"3 1","pages":"39 - 51"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89804293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This paper presents new data derived from field sampling and from a thorough description of lamprophyres located in southeastern Altai and northwestern Mongolia in terms of their mineralogy, textures, and chemical composition. The swarms of alkaline mafic dikes in the area coexist with granosyenite-monzodiorite and gabbro-dolerite intrusions and spatially coincide with an ore district of Sb-Hg, Ag-Sb, Ni-Co-As, Cu-Mo-W, and CaF2 hydrothermal mineralization. All lamprophyres belong to the Early Mesozoic Chuya complex formed in an intracontinental enviroment. Their distribution and orientation is controlled by two large fault zones. The Chuya dikes were investigated at two localities, namely, Yustyd and South-Chuya. The Yustyd lamprophyres intrude Middle-Upper Devonian black shale of the Yustyd depression. At South Chuya, lamprophyres, together with the Tarkhata granosyenite-monzodiorite complex, are hosted by Cambrian and Ordovician metamorphic rocks of the South-Chuya Range. Ar-Ar (phlogopite) and U-Pb (SHRIMP, zircon) ages of the lamprophyre dikes indicate long and continuous period of the formation of the Chuya complex (250-235 Ma). Major- and trace-element compositions of the lamprophyres from both localities and of the syenite indicate their origin from the same magma source. The textures and structures of the lamprophyre and plutonic rocks, their mineral assemblages and the chemistry of the rock-forming minerals provide clues to the evolution of the parental alkaline mafic magma and fluid regime.
{"title":"Petrological implications of the Early Mesozoic lamprophyre dikes and related Tarkhata syenites (SE Altai and NW Mongolia)","authors":"E. Vasyukova, A. Borisenko","doi":"10.2478/MIPO-2013-0002","DOIUrl":"https://doi.org/10.2478/MIPO-2013-0002","url":null,"abstract":"Abstract This paper presents new data derived from field sampling and from a thorough description of lamprophyres located in southeastern Altai and northwestern Mongolia in terms of their mineralogy, textures, and chemical composition. The swarms of alkaline mafic dikes in the area coexist with granosyenite-monzodiorite and gabbro-dolerite intrusions and spatially coincide with an ore district of Sb-Hg, Ag-Sb, Ni-Co-As, Cu-Mo-W, and CaF2 hydrothermal mineralization. All lamprophyres belong to the Early Mesozoic Chuya complex formed in an intracontinental enviroment. Their distribution and orientation is controlled by two large fault zones. The Chuya dikes were investigated at two localities, namely, Yustyd and South-Chuya. The Yustyd lamprophyres intrude Middle-Upper Devonian black shale of the Yustyd depression. At South Chuya, lamprophyres, together with the Tarkhata granosyenite-monzodiorite complex, are hosted by Cambrian and Ordovician metamorphic rocks of the South-Chuya Range. Ar-Ar (phlogopite) and U-Pb (SHRIMP, zircon) ages of the lamprophyre dikes indicate long and continuous period of the formation of the Chuya complex (250-235 Ma). Major- and trace-element compositions of the lamprophyres from both localities and of the syenite indicate their origin from the same magma source. The textures and structures of the lamprophyre and plutonic rocks, their mineral assemblages and the chemistry of the rock-forming minerals provide clues to the evolution of the parental alkaline mafic magma and fluid regime.","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"4 1","pages":"13 - 30"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87857735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-01-01DOI: 10.2478/V10002-007-0030-9
A. Szuszkiewicz, J. Chojcan, Kazimierz Kozakiewicz, M. Sachanbiński
{"title":"Pumpellyite from Miarolitic Pegmatites in the Strzegom-Sobótka Massif, SW Poland","authors":"A. Szuszkiewicz, J. Chojcan, Kazimierz Kozakiewicz, M. Sachanbiński","doi":"10.2478/V10002-007-0030-9","DOIUrl":"https://doi.org/10.2478/V10002-007-0030-9","url":null,"abstract":"","PeriodicalId":18686,"journal":{"name":"Mineralogia","volume":"9 1","pages":"243-254"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84892450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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