scholarly journals Chemical composition of fluid inclusions in the Yorii jadeite–quartz rocks from the Kanto Mountains, Japan

2017 ◽  
Vol 112 (5) ◽  
pp. 281-290 ◽  
Author(s):  
Mayuko FUKUYAMA ◽  
Tatsuhiko KAWAMOTO ◽  
Masatsugu OGASAWARA
Keyword(s):  
Chemical Composition ◽  
Fluid Inclusions

scholarly journals The Ultramicrochemical Analyses (UMCA) of Fluid Inclusions in Halite and Experimental Research to Improve the Accuracy of Measurement

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 823 ◽  
Author(s):  
Anatoliy R. Galamay ◽  
Krzysztof Bukowski ◽  
Daria V. Sydor ◽  
Fanwei Meng
Keyword(s):  
Chemical Composition ◽  
Fluid Inclusions ◽  
Error Rates ◽  
Analytical Error ◽  
Genetic Types ◽  
Primary Fluid ◽  
Accuracy Of Measurement ◽  
Distinguishing Features ◽  
Geological Period

Fluid inclusions in halite are widely used in research to determine the conditions of sedimentation in salt basins and reconstruct the chemical composition of seawater during a specific geological period. However, previous preliminary studies of the genetic types of inclusions, considered in the present research project, have not received due attention. Consequently, we decided to take into account the main distinguishing features of fluid inclusions in halite, belonging to various genetic types. The ultramicrochemical analysis (UMCA) method is one of the several methods that are used for the quantitative determination of the chemical composition of the primary fluid inclusions in halite. We have upgraded that technique, and that allowed us to reduce the analytical error rates of each component determination. The error rates were calculated in the study of Ca-rich and SO4-rich types of natural sedimentary brines.

scholarly journals Rhenium - rich molybdenites in Thracian porphyry Mo±Cu occurrences, NE - Greece

2001 ◽  
Vol 34 (3) ◽  
pp. 1015 ◽  
Author(s):  
Β. ΜΕΛΦΟΣ ◽  
Π. ΒΟΥΔΟΥΡΗΣ ◽  
Κ. ΑΡΙΚΑΣ ◽  
Μ. ΒΑΒΕΛΙΔΗΣ
Keyword(s):  
Chemical Composition ◽  
Hydrothermal Alteration ◽  
Fluid Inclusions ◽  
Mineral Chemistry ◽  
Rare Element ◽  
Alteration Zones ◽  
Porphyry Cu ◽  
Mineral Assemblages ◽  
Host Rocks

The present study correlates both the mineralogy of the hydrothermal alteration and the mineral chemistry of molybdenites from three porphyry Mo ± Cu occurrences in Thrace: Melitena, Pagoni Rachi/Kirki and Ktismata/ Maronia. The mineralisations are genetically related to calcalkaline, subvolcanic bodies of Tertiary age. According to their mineralogical and chemical composition the host rocks are characterized as dacite (Melitena), dacitic andésite (Pagoni Rachi) and porphyry microgranite (Ktismata/Maronia). The molybdenites occur in disseminated form, as fracture fillings, as well within quartz stockworks crosscuting the central alteration zones of the intrusives. They are accompanied by the following mineral assemblages: quartz, sericite, pyrophyllite, diaspore, Ca-Ba-rich alunite, pyrite (Melitena); quartz, albite/K-feldspar, biotite, actinolite, magnetite (Pagoni Rachi); and sericite, kaolinite, pyrophyllite, chlorite (Ktismata). Preliminary microthermometric results showed homogenisation temperatures from 352° to 390 °C for Pagoni Rachi area and from 295° to 363 °C for Melitena area. The salinities range between 4.5 and 6.1 wt% eq. NaCl and between 2.7 and 3.4 wt% eq. NaCl, respectively. Detailed study on over 400 fluid inclusions from the porphyry Cu-Mo deposit in Maronia area revealed formation temperatures from 300° to 420 °C, whereas salinities are distincted in two different groups from 6 to 16 wt% eq. NaCl and from 28 to 55 wt% eq. NaCl. The chemical composition of the molybdenites from the three porphyry Mo±Cu deposits in Thrace was studied with 155 microprobe analyses. The results revealed unusual high and variable Re concentrations in the studied molybdenites. Re content in molybdenite from Melitena area vary from 0.21 to 1.74 wt%, 0.79 wt% on average. The highest values were measured in samples from Pagoni Rachi (0.45-4.21 wt%, 1.98 wt% on average). Finally, microprobe analyses from molybdenite in Ktismata/Maronia showed Re content between 0.12 and 2.88 wt% (0.76 wt% on average). Rhenium is a very rare element with many definite uses, and is mainly associated with molybdenite in porphyry type deposits. According to the data published so far the Re content in molybdenite reaches up to 0.42 wt%. It is obvious therefore that such high Re concentrations (0.12 to 4.22 wt%) from the studied molybdenites in Thrace, are very ineresting for a possible future exploitation.

Transmission electron microscopy investigations of (hydrous) chain silicates from the lithospheric mantle beneath the Carpathian Pannonian Region

2020 ◽  
Author(s):  
Zsófia Pálos ◽  
Péter Pekker ◽  
Mihály Pósfai ◽  
Thomas Pieter Lange ◽  
Nóra Liptai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chemical Composition ◽  
Fluid Inclusions ◽  
Lithospheric Mantle ◽  
Ion Beam ◽  
Mantle Xenoliths ◽  
Formation Mechanisms ◽  
Alkaline Basalt ◽  
Transmission Electron

<p>Transmission electron microscopy (TEM) is a powerful, yet scarcely used technique when it comes to investigating mantle minerals and fluid inclusions. It is capable to collect structural information of the studied mineral, its precise chemical composition, and makes nanofeatures visible, such as dislocations and nano-inclusions.</p><p>In this study TEM and STEM (scanning transmission electron microscopy) measurements were carried out on a set of ortho- and clinopyroxene samples from central and marginal localities of Carpathian Pannonian region (CPR), where Plio-Pleistocene alkaline basalt volcanism sampled the lithospheric mantle retrieving lithospheric mantle xenoliths. Objective of the study was to constrain the presence and formation mechanisms of sub-microscopic occurrence of pargasitic amphibole.</p><p>The detailed investigation of pargasite in the upper mantle is rather timely, because its presence may be the major cause for the rheologic contrast experienced between the lithosphere and the asthenosphere [1], [2]. The nominally anhydrous minerals’ (NAMs, as ortho- and clinopyroxene) structural hydroxyl [3] content or volatiles in fluid inclusions could lead to formation of pargasite [4]. In addition, pargasite could form interstitially during metasomatic intereactions.</p><p>Our observations so far suggest that hydrous silicate formation as sub-solidus exsolution in the central CPR may not have taken place. Ordering of the Ca forming Ca-rich and Ca-poor domains in an orthopyroxene grain was identified. Precursors of H<sup>+</sup> diffusion were also recorded, such as dislocations and nanosized fluid inclusions. Diffusion of H<sup>+</sup> could be active in the lattice scale through the disclinations along subgrain boundaries [3], [5] or dislocations in the host mineral along the boundary of nanoscale fluid inclusions [6], [7]. Clinopyroxene-amphibole phase boundary has been prepared by focused ion beam (FIB) milling technique from the marginal area of CPR. The chemical composition of the amphibole lamella provides evidence that the H<sub>2</sub>O content of the nearby fluid inclusion migrated into the host clinopyroxene producing an amphibole lamella growing along the ‘c’ crystallographic axis [4].</p><p>Observations of the boundary of clinopyroxene and amphibole confirm that the amphibole octahedral layers penetrate the clinopyroxene structure. The precise nanoscale measurements (STEM mapping) of chemical composition of both the host and the lamellae can lead to profound implications on the original composition of the studied fluid inclusions.</p><p>[1] Green, D. H., Hibberson, W. O., Kovács, I. J., & Rosenthal, A. (2010). <em>Nature</em>, 467(7314), 448–451.</p><p>[2] Kovács, I. J., Lenkey, L., Green, D. H., Fancsik, T., Falus, G., Kiss, J., Orosz, L., Angyal, J., Vikor, Zs. (2017). <em>Acta Geodaetica et Geophysica</em>, 52, 183–204.</p><p>[3] Liptai, N., Kovács, I.J., Lange, T.P., Pálos, Zs., Berkesi, M., Szabó, Cs., Wesztergom, V. (2019). <em>Goldschmidt Abstracts</em>, 2019 1981.</p><p>[4] Lange, T.P., Liptai, N., Patkó, L., Berkesi, M., Kesjár, D., Szabó, Cs., Kovács, I. J. (2019). 25th European Current Research on Fluid Inclusions (ECROFI) , <em>Abstract Series</em>, 68.</p><p>[5] Demouchy, S., & Bolfan-Casanova, N. (2016). <em>Lithos</em>, 240–243, 402–425.</p><p>[6] Bakker, R. J., & Jansen, J. B. H. (1994). <em>Contributions to Mineralogy and Petrology</em>, 116, 7–20.</p><p>[7] Viti, C., & Frezzotti, M. L. (2000). <em>American Mineralogist</em>, 85(10), 1390–1396.</p>

ENRICHMENT OF COPPER IN ORE-FORMING FLUID OF COPPER-TUNGSTEN MINERALIZATION OF THE YAMAGUCHI SKARN DEPOSIT, IWATE, JAPAN

1999 ◽  
Vol 09 (03n04) ◽  
pp. 431-439 ◽  
Author(s):  
D. ISHIYAMA ◽  
T. OGATA ◽  
H. SATOH ◽  
T. MIZUTA ◽  
K. SERA ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Fluid Inclusions ◽  
New South ◽  
Massive Sulfide ◽  
Deionized Water ◽  
Molar Ratio ◽  
Skarn Deposit ◽  
Sulfide Deposits ◽  
Cu Content ◽  
South Wales

Chemical composition of the fluids in the fluid inclusions of quartz from the pegmatite veins of the Yamaguchi W - Cu skarn deposit was measured by a combination of the crush-leach method in deionized water and chemical analysis using PIXE. Chemical composition of the fluids is characterized by a low molar ratio of Na/K and a high Cu concentration. The molar ratio of Cu /( Cu + Fe + Zn ) of the fluid inclusions is higher than that of massive sulfide deposits on the seafloor. The molar ratio of Cu /( Cu + Fe + Zn ) of the fluid inclusions is similar to the ratios of the vapor-rich fluid inclusions from the quartz-cassiterite veins hosted within the Mole Granite in New South Wales, Australia. The high Cu concentration in fluid inclusions of quartz associated with the pegmatite veins from the Yamaguchi deposit suggests that the fluid emanating from the Miyako granitic melt at the later stage of crystallization had a high Cu content.

scholarly journals Halogenases of Qarhan Salt Lake in the Qaidam Basin: Evidence From Halite Fluid Inclusions

2021 ◽  
Vol 9 ◽  
Author(s):  
Jun Li ◽  
Xiying Zhang ◽  
Mingyue Hu ◽  
Wenxia Li ◽  
Weiliang Miao ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Fluid Inclusions ◽  
Deep Water ◽  
Salt Lake ◽  
Salt Lakes ◽  
Salt Layer ◽  
Formation Stage ◽  
Evolution Stage ◽  
Qarhan Salt Lake ◽  
Tectonic Activities

The fluid inclusion composition of halite can help track chemical composition of ancient fluids and, thus, serves as a reliable index to analyze ancient brine in salt lakes. Qarhan Salt Lake (QSL) is the largest potash brine deposit in China. Although the mixing of modern river water and Ca-Cl deep water is widely accepted as potassium formation, the mixing characteristics in the time domain and driving factors of deep water are still unclear. Here, the chemical composition of fluid inclusions in primary halite samples collected from the ISL1A borehole in QSL was measured by LA-ICP-MS technology. The analysis results show that, during the formation stage of the S4 salt layer in QSL, the main potassium salt layer, the contents of Ca2+ and Sr2+ in brine increased significantly. There is evidence confirming that Ca-Cl deep water is beneficial to the enrichment of potassium and the surrounding rivers generally develop terraces. It suggests that, during the formation stage of the QSL potassium salt layer, more Ca-Cl inflow water of the northern margin supplies the salt lake, inferring that it was driven by tectonic activities. In addition, the chemical composition of halite fluid inclusions shows that there is an anomaly in geochemistry at the early stage of salt formation in QSL. By combining the time of tectonic activities, it is inferred that the anomaly is not caused by tectonic activities but maybe caused by a salt-forming event. This work indicates that deep water and tectonic movement have a huge impact on the evolution of salt lakes. Therefore, it is necessary to consider the influence of deep water and tectonic activities on the salt-forming evolution stage of salt lakes when studying the salt-forming evolution stage of salt lakes and paleoclimate by using salt lake deposition.

scholarly journals PŮVOD A CHEMICKÉ SLOŽENÍ FLUID POVARISKÉ HYDROTERMÁLNÍ MINERALIZACE NA LOKALITĚ ZLATÝ DŮL U HLUBOČEK (SPODNÍ KARBON NÍZKÉHO JESENÍKU)

2016 ◽  
Vol 23 (1-2) ◽  
Author(s):  
Michaela Kotlánová ◽  
Zdeněk Dolníček
Keyword(s):  
Stable Isotopes ◽  
Organic Matter ◽  
Chemical Composition ◽  
Fluid Inclusions ◽  
Meteoric Water ◽  
Lower Carboniferous ◽  
Primary Fluid ◽  
Moderate Salinity ◽  
Homogenization Temperatures ◽  
Secondary Fluid

Origin and chemical composition of fluids of hydrothermal ore veins at historical deposit Zlatý důl near Hlubočky (Lower Carboniferous of the Nízký Jeseník Upland) were studied using petrography, microthermometry and crush-leach analysis of fluid inclusions and analysis of stable isotopes of oxygen and carbon in carbonates, oxygen in quartz and sulphur in sulphides. Studied mineralization has epithermal and partly mesothermal character (Th = < 50 to 293 °C). The H2O-NaCl-CaCl2 system is mostly enclosed in the primary fluid inclusions in minerals of post-Variscan ore veins. These fluids had low to medium homogenization temperatures (68 to 293 °C) and moderate to high salinities (19–27 wt. % NaCl eq.). In contrast, low to moderate salinity (0–10 wt. % NaCl eq.) fluids of the system H2O-NaCl-KCl-(MgCl2-FeCl2) with low homogenization temperatures (< 50 to 110 °C) were enclosed in secondary fluid inclusions. The main source of water was probably evaporated seawater for older fluids. The source of carbon was in carbon of the homogenized Earth’s crust and partly in carbon of organic matter. Meteoric water is the main source for younger fluids. Origin of sulphur of sulphides is in the surrounding Lower Carboniferous sediments (shales). The high content of SO4 in fluids hosted by Fe-rich dolomite suggests the origin of the fluids in the evaporated Permian basins. Studied older quartz-galena vein is probably Variscan in age. Genetically similar mineralization can be found also at other localities in the Moravo-Silesian Lower Carboniferous (Culm, siliciclastics of the Lower Carboniferous age).

scholarly journals BERILOS DE PEGMATITOS DE SANTA MARIA DE ITABIRA, MINAS GERAIS - BRASIL

1994 ◽  
Author(s):  
Vitória Régia P.R.O. Marciano ◽  
Francisco Javier Rios ◽  
Adriana B. Achtschin ◽  
José Marques Correia Neves ◽  
Darcy P. Svisero
Keyword(s):  
Trace Elements ◽  
Chemical Composition ◽  
Fluid Inclusions ◽  
Analytical Techniques ◽  
Minas Gerais ◽  
Point Of View ◽  
Cell Parameters ◽  
Santa Maria

Samples of beryls from three different pegmatite bodies, representative of the Santa Maria de Itabiraregion have been studied by several analytical techniques: Color, refraction, luminescence, density, IRspectrum, XRD, cell parameters, fluid inclusions and chemical composition have been considered. Theberyls have been analyzed for main elements as well as the following trace elements Na, Li, Cs, K, Rb, Ca,Ba, Zr. Fe e Ti.The pegmatites described in this paper are situated at the southeastern side of São Francisco Craton andbelong to the Eastern Pegmatite Province (PPO). They are related to a magmatism of Brasiliano age. Theyare being exploited for beryl and gems such as aquamarine, heliodor, colorless topaz and amazonite.The data are discussed and interpreted from the petrologic and metallogenetic point of view.

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