Again About the "Magmatic" Nature of Topaz Crystals From Chamber Pegmatites of Volyn (Ukrainian Shield)

2021 ◽  
Vol 43 (4) ◽  
pp. 87-97
Author(s):  
D.K. VOZNYAK ◽  
V.M. BELSKYI
Keyword(s):  
Aqueous Solution ◽  
Fluid Inclusions ◽  
Aqueous Suspension ◽  
Fluid Pressure ◽  
Equilibrium Form ◽  
Mineral Inclusions ◽  
Mineral Phases ◽  
Primary Fluid ◽  
The Face ◽  
Negative Crystal

Various aspects of the genesis of primary fluid inclusions (0.01-1.0 sometimes up to 2 mm) with a large number of mineral inclusions in topaz crystals from chamber pegmatites of Volyn were analyzed. The data could be interpreted in two fundamentally different ways. The first argues for crystals grown in a magmatic melt; the second for an aqueous solution, with a density close to critical. The essence of the discrepancy is the reliability of the identification of the nature of mineral phases in the primary inclusions, if they are crystals captured during growth (xenogenic) or daughter crystals from the fluid. The xenogenic origin of the phases is indicated by the following observations: 1) The location of the mineral inclusions on the growing faces of the topaz crystals depends on the orientation of the crystal’s axis [001] relative to the horizontal plane. It determines the faces on which small mineral phases could be deposited from an aqueous suspension during the growth of topaz crystals. The studied crystals are dominated by individuals in which the mineral inclusions are located on the growing faces {011}, {021}, (001) (and others) of the crystal head. During growth, they were approximately in an upright position. 2) The filling of primary fluid inclusions is not constant. The volume of mineral phases in the inclusions varies from 40 to 95%, often 70-75%, the rest of the volume is gas and aqueous solution. Liquid-gas (liquids ˂ 40%) inclusions without or with < 5% solid phases are very rare. In addition, the ratio between the volumes of different mineral phases in the inclusions is not constant. 3) Light rims (Becke lines) around the inclusions record a change in the refractive indices (caused by a different chemical composition) of topaz when inclusions are acquiring the equilibrium form of the negative crystal. 4) The xenogenic nature of the mineral phases of the primary fluid inclusions in topaz is indirectly confirmed by the value of the fluid pressure (260-300 MPa)of the magmatic melt (determined by the method of homogenization of these inclusions), as it denies the possibility of chamber pegmatite formation at depths of 9-11 km. Thus, the peculiar mineral inclusions were deposited on the face of growing topaz crystals of small mineral phases from a turbid aqueous suspension, which boiled violently. We conclude that topaz crystals in chamber pegmatites of Volyn grew in aqueous solution at a temperature of 380-415ºС and a pressure of 30-40 MPa.

Fluid and mineral inclusions in corundum from gem gravels in Sri Lanka

1989 ◽  
Vol 53 (373) ◽  
pp. 539-545 ◽  
Author(s):  
A. A. de Maesschalck ◽  
I. S. Oen
Keyword(s):  
Sri Lanka ◽  
Fluid Inclusions ◽  
Granulite Facies ◽  
Granulite Facies Metamorphism ◽  
Source Areas ◽  
Mineral Inclusions ◽  
Primary Fluid ◽  
Facies Metamorphism ◽  
Secondary Fluid

AbstractMineral and fluid inclusions were studied in seven gem corundums from gravels of three areas in Sri Lanka. All fluid inclusions are pure CO2. Microthermometry results on primary fluid inclusions suggest formation of corundum under granulite facies metamorphism (>630°C, 5.5 kbar). Secondary fluid inclusions indicate different retrograde events of post-metamorphic cooling and uplift for different source areas.

TEM observation of iron oxide pillars in montmorillonite

1990 ◽  
Vol 48 (4) ◽  
pp. 882-883
Author(s):  
H. Mori ◽  
Y. Murata ◽  
H. Yoneyama ◽  
H. Fujita
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Fine Particles ◽  
Aqueous Suspension ◽  
Volume Ratio ◽  
Exchange Capacity ◽  
Nano Composites ◽  
Pillared Montmorillonite ◽  
Topographic Features ◽  
Transmission Electron

Recently, a new sort of nano-composites has been prepared by incorporating such fine particles as metal oxide microcrystallites and organic polymers into the interlayer space of montmorillonite. Owing to their extremely large specific surface area, the nano-composites are finding wide application[1∼3]. However, the topographic features of the microstructures have not been elucidated as yet In the present work, the microstructures of iron oxide-pillared montmorillonite have been investigated by high-resolution transmission electron microscopy.Iron oxide-pillared montmorillonite was prepared through the procedure essentially the same as that reported by Yamanaka et al. Firstly, 0.125 M aqueous solution of trinuclear acetato-hydroxo iron(III) nitrate, [Fe3(OCOCH3)7 OH.2H2O]NO3, was prepared and then the solution was mixed with an aqueous suspension of 1 wt% clay by continuously stirring at 308 K. The final volume ratio of the latter aqueous solution to the former was 0.4. The clay used was sodium montmorillonite (Kunimine Industrial Co.), having a cation exchange capacity of 100 mequiv/100g. The montmorillonite in the mixed suspension was then centrifuged, followed by washing with deionized water. The washed samples were spread on glass plates, air dried, and then annealed at 673 K for 72 ks in air. The resultant film products were approximately 20 μm in thickness and brown in color.

Immobilization of ZnO Suspension on Glass Substrate to Remove Filtration During the Removal of Remazol Red R from Aqueous Solution

2016 ◽  
Vol 12 (6) ◽  
pp. 4127-4133
Author(s):  
Nazmul Kayes ◽  
Jalil Miah ◽  
Md. Obaidullah ◽  
Akter Hossain ◽  
Mufazzal Hossain
Keyword(s):  
Aqueous Solution ◽  
Glass Substrate ◽  
Uv Light ◽  
Aqueous Suspension ◽  
Light Irradiation ◽  
Zno Films ◽  
Light Sources ◽  
Zno Film ◽  
Semiconductor Oxides ◽  
Remazol Red

Photodegradation of textile dyes in the presence of an aqueous suspension of semiconductor oxides has been of growing interest. Although this method of destruction of dyes is efficient, the main obstacle of applying this technique in the industry is the time and cost involving separation of oxides from an aqueous suspension. In this research, an attempted was made to develop ZnO films on a glass substrate by simple immobilization method for the adsorption and photodegradation of a typical dye, Remazol Red R (RRR) from aqueous solution. Adsorption and photodegradation of  RRR were performed in the presence of glass supported ZnO film. Photodegradation of the dye was carried out by varying different parameters such as the catalyst dosage, initial concentrations of RRR, and light sources. The percentage of adsorption as well as photodegradation increased with the amount of ZnO, reaches a maximum and then decreased. Maximum degradation has been found under solar light irradiation as compared to UV-light irradiation. Removal efficiency was also found to be influenced by the pre-sonication of ZnO suspension.

scholarly journals The Temperature of Halite Crystallization in the Badenian Saline Basins, in the Context of Paleoclimate Reconstruction of the Carpathian Area

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 831
Author(s):  
Anatoliy R. Galamay ◽  
Krzysztof Bukowski ◽  
Igor M. Zinczuk ◽  
Fanwei Meng
Keyword(s):  
Temperature Distribution ◽  
Air Temperature ◽  
Fluid Inclusions ◽  
Middle Miocene ◽  
Single Phase ◽  
Dead Sea ◽  
Paleoclimate Reconstruction ◽  
Near Surface ◽  
Carpathian Region ◽  
Primary Fluid

Currently, fluid inclusions in halite have been frequently studied for the purpose of paleoclimate reconstruction. For example, to determine the air temperature in the Middle Miocene (Badenian), we examine single-phase primary fluid inclusions of the bottom halites (chevron and full-faceted) and near-surface (cumulate) halites collected from the salt-bearing deposits of the Carpathian region. Our analyses showed that the temperatures of near-bottom brines varied in ranges from 19.5 to 22.0 °C and 24.0 to 26.0 °C, while the temperatures of the surface brines ranged from 34.0 to 36.0 °C. Based on these data, such as an earlier study of lithology and sedimentary structures of the Badenian rock salts, the crystallization of bottom halite developed in the basin from concentrated and cooled near-surface brines of about 30 m depth. Our results comply with the data on the temperature distribution in the modern Dead Sea.

scholarly journals Emplacement and biodegradation of oil in fractured basement: the ‘coal’ deposit in Moinian gneiss at Castle Leod, Ross-shire

2016 ◽  
Vol 107 (1) ◽  
pp. 23-32 ◽  
Author(s):  
John Parnell ◽  
Mas'ud Baba ◽  
Stephen Bowden
Keyword(s):  
Lower Devonian ◽  
Fluid Pressure ◽  
Low Permeability ◽  
Coal Deposit ◽  
Basin Inversion ◽  
Mineral Phases ◽  
Metamorphic Basement ◽  
Major Fault ◽  
High Fluid ◽  
Transfer Faults

ABSTRACTBitumen veins were formerly mined as ‘coal’ from Moinian metamorphic basement at Castle Leod, Strathpeffer, Ross-shire. The abundance and spatial concentration of hydrocarbons implies generation of a large volume of oil that exerted a fluid pressure great enough to open veins to 1+ m width. Biomarker characteristics, including β-carotane and a high proportion of C28 steranes, correlate the bitumen to Lower Devonian non-marine shales separated from the Moinian basement by a major fault. Bitumen in the Moinian basement has higher diasterane/sterane ratios than bitumen in the Devonian sequence, indicating greater levels of biodegradation, which may reflect more interaction with water in the basement. Replacive bitumen nodules in the Moinian basement, containing thoriferous/uraniferous mineral phases, are comparable with bitumen nodules in basement terrains elsewhere. Formation of the nodules represents hydrocarbon penetration of low-permeability basement, consistent with high fluid pressure. Bitumen veins are particularly orientated E–W, and may be associated with E–W transfer faults attributed to Permo-Carboniferous basin inversion.

Oxygen fugacity during tin ore deposition from primary fluid inclusions in cassiterite

2021 ◽  
pp. 104451
Author(s):  
Christian Schmidt ◽  
Matthias Gottschalk ◽  
Rongqing Zhang ◽  
Jianjun Lu
Keyword(s):  
Oxygen Fugacity ◽  
Fluid Inclusions ◽  
Primary Fluid ◽  
Ore Deposition

Microanalysis of primary fluid inclusions in halite: constraints for an evaporitic sedimentation modeling. Application to the Mulhouse Basin (France)

1993 ◽  
Vol 20 (8) ◽  
pp. 1139-1151 ◽  
Author(s):  
A. Canals ◽  
B. Carpenter ◽  
A.Y. Huc ◽  
N. Guilhaumou ◽  
M.H. Ramsey
Keyword(s):  
Fluid Inclusions ◽  
Primary Fluid

Guidelines for assessing the provenance of Mesozoic and Cenozoic clastic successions sourced by pre-Jurassic basement complexes in southernmost North America

2020 ◽  
Vol 90 (5) ◽  
pp. 513-532 ◽  
Author(s):  
Michelangelo Martini ◽  
Luigi Solari ◽  
Mariana Peña-Guerrero ◽  
Mildred Zepeda-MartÍnez ◽  
Chiara Montomoli
Keyword(s):  
North America ◽  
White Mica ◽  
Heavy Minerals ◽  
Geochemical Data ◽  
Provenance Analysis ◽  
Mineral Phases ◽  
The Face ◽  
Rank 2 ◽  
Available Information ◽  
Different Sources

ABSTRACT Mexico is an attractive place for provenance studies focused on reconstructing the tectonic evolution of North America. This is because Mexico hosts a well-preserved clastic record associated with some of the major Mesozoic and Cenozoic tectonic processes that shaped the face of this continent. However, the available information on Mexican pre-Mesozoic source terranes is presently insufficient for provenance analysis. With the aim of drawing the guidelines for provenance determination, we present here detrital modes, geochemical data, and zircon U-Pb ages for detritus derived from pre-Jurassic basement complexes of Mexico. Our data show that the various basement complexes produce distinctive detrital modes and supply diagnostic and compositionally different detrital heavy minerals that represent powerful provenance tracers. The Oaxacan Complex, Ayú Complex, and East Mexico Arc are the main sources of quartzo-feldspathic and feldspatho-quartzose detritus. Quartz with rutile needles, mesoperthitic K-feldspar, orthopyroxene, augitic to diopsidic clinopyroxene, and Mg- to Ca-rich almandine (Alm71–52Grs7–3Prp43–23Sps3–1Alm74–56Grs21–19Prp23–2Sps5–2) are common minerals in detritus from the Oaxacan Complex. The Ayú Complex supplies detritus marked by the occurrence of sagenitic biotite and white mica, as well as Mn-rich almandine (Alm69–66Grs4–3Prp18–11Sps19–10). Detritus from the East Mexico Arc contains any of these mineral phases ubiquitous in the Oaxacan and Ayú complexes. The Acatlán Complex is the main source of detritus dominated by metamorphic lithic grains and quartz, with minor amounts of feldspar. Lithic grains are rank 2–4 metabasitic, metapelitic, and metapsammitic–metafelsitic fragments. Diagnostic mineral phases are schorl–dravitic tourmaline, Na-amphibole, and helycitic garnet varying from a Ca- to Mn-rich almandine (Alm74–55Grs34–15Prp16–3Sps12–1-Alm70–46Grs20–15Prp3–1Sps32–12). Zircon U-Pb geochronology proves to have some virtues but also major limitations because: 1) the zircon U-Pb age signature of many different sources in Mexico is similar and 2) zircon documents a limited number of sources because of variations in zircon fertility.

The Witwatersrand pyrites and metamorphism

1983 ◽  
Vol 47 (345) ◽  
pp. 473-479 ◽  
Author(s):  
D. K. Hallbauer ◽  
K. von Gehlen
Keyword(s):  
Trace Element ◽  
Fluid Inclusions ◽  
Depositional Environment ◽  
Volcanic Rocks ◽  
Source Rocks ◽  
Fine Grained ◽  
Mineral Inclusions ◽  
Ore Minerals ◽  
Hand Specimen

AbstractEvidence obtained from morphological and extensive trace element studies, and from the examination of mineral and fluid inclusions in Witwatersrand pyrites, shows three major types of pyrite: (i) detrital pyrite (rounded pyrite crystals transported into the depositional environment); (ii) synsedimentary pyrite (round and rounded aggregates of fine-grained pyrite formed within the depositional environmen); and (iii) authigenic pyrite (newly crystallized and/or recrystallized pyrite formed after deposition). The detrital grains contain mineral inclusions such as biotite, feldspar, apatite, zircon, sphene, and various ore minerals, and fluid inclusions with daughter minerals. Most of the inclusions are incompatible with an origin by sulphidization. Recrystallized authigenic pyrite occurs in large quantities but only in horizons or localities which have been subjected to higher temperatures during the intrusion or extrusion of younger volcanic rocks. Important additional findings are the often substantial amounts of pyrite and small amounts of particles of gold found in Archaean granites (Hallbauer, 1982) as possible source rocks for the Witwatersrand detritus. Large differences in Ag and Hg content between homogeneous single gold grains within a hand specimen indicate a lack of metamorphic homogenization. The influence of metamorphism on the Witwatersrand pyrites can therefore be described as only slight and generally negligible.

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