scholarly journals Výskyty hydrotermálnej Sb-Au mineralizácie na lokalitách Lomnistá, Husárka a Suchá dolina pri Jasení (Nízke Tatry)

2020 ◽  
Vol 28 (1) ◽  
pp. 210-218
Author(s):  
Štefan Čík ◽  
Martin Chovan ◽  
Juraj Majzlan
Keyword(s):  
Primary Sources ◽  
Two Phase ◽  
Alluvial Sediments ◽  
Secondary Minerals ◽  
Reflected Light ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Homogenization Temperatures ◽  
Rock Alteration ◽  
Phase Fluid

Ore mineralization in small Sb-Au occurrences Lomnistá, Husárka and Suchá dolina (Nízke Tatry Mts., Western Carpathians) was investigated by reflected-light microscopy, electron microprobe, fluid inclusion measurements, identification of host rock alteration and secondary minerals. Hydrothermal Sb-Au mineralization was formed during the arsenopyrite-pyrite-gold and stibnite-Pb-Sb-sulfosalts stages. The first stage of mineralization consists of arsenopyrite, pyrite, and quartz, but gold, typical for this stage in the Nízke Tatry Mts. is missing. Stibnite and zinkenite are dominant in the following stage in Lomnistá and Husárka. Berthierite and jamesonite are frequent in Suchá dolina. Other ore minerals identified here are sphalerite, chalcostibite, chalcopyrite, cinnabar, tetrahedrite-(Hg) at Lomnistá and Husárka and pyrrhotite, chalcostibite, tetrahedrite-(Fe), chalcopyrite, antimony, and gold in Suchá dolina. Identified secondary minerals are valentinite and stibiconite. Stibnite, gold, and other ore minerals were found in heavy-mineral fractions from alluvial sediments, pointing at short transport from the primary sources. Two quartz samples, thought to be related to stibnite or berthierite, contained two-phase fluid inclusions with salinity of 10 - 20 wt.% NaCl eq. The total homogenization temperatures are 230 - 330 ºC in Lomnistá and 200 - 260 ºC in Suchá dolina.

scholarly journals Ore Genesis of the Chuduoqu Pb-Zn-Cu Deposit in the Tuotuohe Area, Central Tibet: Evidence from Fluid Inclusions and C–H–O–S–Pb Isotopes Systematics

Minerals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 285 ◽  
Author(s):  
Yong-Gang Sun ◽  
Bi-Le Li ◽  
Feng-Yue Sun ◽  
Ye Qian ◽  
Run-Tao Yu ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Stage Iv ◽  
Isotopic Compositions ◽  
Ore Bodies ◽  
Metallogenic Belt ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Deposit Type ◽  
Homogenization Temperatures ◽  
Central Tibet

The Chuduoqu Pb-Zn-Cu deposit is located in the Tuotuohe area in the northern part of the Sanjiang Metallogenic Belt, central Tibet. The Pb-Zn-Cu ore bodies in this deposit are hosted mainly by Middle Jurassic Xiali Formation limestone and sandstone, and are structurally controlled by a series of NWW trending faults. In this paper, we present the results of fluid inclusions and isotope (C, H, O, S, and Pb) investigations of the Chuduoqu deposit. Four stages of hydrothermal ore mineralization are identified: quartz–specularite (stage I), quartz–barite–chalcopyrite (stage II), quartz–polymetallic sulfide (stage III), and quartz–carbonate (stage IV). Two types of fluid inclusions are identified in the Chuduoqu Pb-Zn-Cu deposit: liquid-rich and vapor-rich. The homogenization temperatures of fluid inclusions for stages I–IV are 318–370 °C, 250–308 °C, 230–294 °C, and 144–233 °C, respectively. Fluid salinities range from 2.07 wt. % to 11.81 wt. % NaCl equivalent. The microthermometric data indicate that the fluid mixing and cooling are two important mechanisms for ore precipitation. The H and O isotopic compositions of quartz indicate a primarily magmatic origin for the ore-forming fluids, with the proportion of meteoric water increasing over time. The C and O isotopic compositions of carbonate samples indicate that a large amount of magmatic water was still involved in the final stage of mineralization. The S and Pb isotopic compositions of sulfides, demonstrate that the ore minerals have a magmatic source. On a regional basis, the most likely source of the metallogenic material was regional potassium-enriched magmatic hydrothermal fluid. Specifically for the Chuduoqu Pb-Zn-Cu deposit, the magmatic activity of a syenite porphyry was the likely heat source, and this porphyry also provided the main metallogenic material for the deposit. Mineralization took place between 40 and 24 Ma. The Chuduoqu deposit is a mesothermal hydrothermal vein deposit and was formed in an extensional environment related to the late stage of intracontinental orogenesis resulting from India–Asia collision. The determination of the deposit type and genesis of Chuduoqu is important because it will inform and guide further exploration for hydrothermal-type Pb and Zn deposits in the Tuotuohe area and in the wider Sanjiang Metallogenic Belt.

THE CHARACTERISTICS OF ORE MINERALIZATION IN THE WEISSWASSER COPPER DISTRICT, GERMANY

2017 ◽  
pp. 0-0
Author(s):  
Henryk KUCHA ◽  
Bartłomiej BIL
Keyword(s):  
Morphological Changes ◽  
Copper Sulphide ◽  
The North ◽  
Tectonic Events ◽  
Framboidal Pyrite ◽  
Reflected Light ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Native Silver ◽  
North Western

The research deals with drill core samples collected during exploration of copper in the Weisswasser area in Saxony. The area is the north-western part of the North-Sudetic Basin, the lithostratigraphic section of which is similar to the typical one known from the Lubin district. As a result of mineralogical observations using reflected light microscopy and scanning electron microscopy, the following minerals were identified: chalcopyrite, chalcocite, bornite, digenite, galena, sphalerite, native silver, Ag-amalgams, mckinstyite, anilite and betechtinite. Detailed characteristics of the occurrence of sulphide mineralization is presented, describing its form, mutual inclusions and paragenesis, relationship to microtectonic conditions, as well as implications of morphological changes on the bottom of the Zechstein. Three forms of mineralization were found: (1) horizontal, mid-layered copper sulphide lenses formed by hydraulic peeling along the sludge lamination surfaces caused by mineralized high-pressure solutions, (2) horizontal copper sulphide lenses replacing previous framboidal pyrite lenses, and (3) replacement of bioclasts. Copper sulphides were concentrated at the expense of sulphur deposited during sedimentation and early diagenesis as bacterial pyrite. Ore mineralization occurs in the thin horizon with an extensive microtectonic net. Two tectonic episodes can be distinguished: Mesozoic tectonic events that enabled seismic pumping of hot fluids, and microfractures that developed during ore minerals precipitation. Futhermore, single sharp-edged grains of chalcopyrite disturbing lamination of copper shale are observed. It indicates the displacement of grains from crushed conglomerate and resedimentation together with copper shale.

scholarly journals Origin of the Kyaukmyet Low-Sulfidation Epithermal Gold Prospect, Monywa District, Central Myanmar

2021 ◽  
Vol 54 (1E) ◽  
pp. 1-18
Author(s):  
Toe Oo ◽  
Agung Harijoko ◽  
Lucas Setijadji
Keyword(s):  
Magmatic Fluid ◽  
Epithermal Gold ◽  
Quartz Veins ◽  
Mineral Assemblages ◽  
Epithermal Gold Deposit ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Alteration Minerals ◽  
Homogenization Temperatures ◽  
Low Sulfidation

The Kyaukmyet prospect is one of the principal epithermal gold prospects in the Monywa District, Central Myanmar; its gold- and base metal-bearing quartz veins contain around 3 g/t gold. Ore minerals are mainly hosted by volcanic and volcaniclastic rocks of the Late Oligocene to Middle Miocene Magyigon Formation. The distribution of magmatic intrusions in the area is controlled by ENE-WSW trending faults; these faults are likely related to ore mineralization. Common ore minerals at the Kyaukmyet prospect include pyrite, sphalerite, galena, chalcopyrite, and electrum. They occur in mineralized crustiform-textured brecciated quartz veins and banded (colloform) and massive quartz veins. Mineralized rock is accompanied by silicification and propylitic and argillic alterations. The alteration mineral assemblages include quartz, adularia, calcite, chlorite, illite/smectite, sericite, and illite. Fluid inclusions in the quartz veins have homogenization temperatures ranging from 148 °C to 304 °C and salinities from 0.35 wt % to 2.75 wt % NaCl equiv. The quartz in the mineralized quartz veins was most likely precipitated at a depth ranges165-256 m below the paleosurface. The precipitation of gold at the Kyaukmyet prospect may have been formed by mixing large amounts of meteoric fluid with small amounts of magmatic fluid. The coexistence of liquid-rich and vapor-rich inclusions and presence of adularia and bladed calcite indicate that fluid boiling is caused the main mechanism of ore formation. The vein textures, ore mineral assemblages, alteration minerals and fluid inclusion data suggest that the Kyaukmyet prospect is a polymetallic low-sulfidation epithermal gold deposit.

scholarly journals Geochemistry of tetrahedrite group minerals and associated silver paragenesis in the Boguszów baryte deposit, Poland

2020 ◽  
Vol 64 (4) ◽  
Author(s):  
Sławomir Mederski ◽  
Jaroslav PRSEK ◽  
Żaneta Niemasz
Keyword(s):  
Textural Features ◽  
Upper Carboniferous ◽  
Reflected Light ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Crystallization Conditions ◽  
Low Temperature Crystallization ◽  
Small Grains ◽  
The 19Th Century ◽  
Temperature Crystallization

Primary ore mineralization in the abandoned Boguszów baryte-polymetallic deposit, located in the Intra-Sudetic Depression, was studied by reflected light microscopy and electron microprobe. Ore minerals, occurring as veinlets, irregular aggregates and lenses in baryte veins are hosted by the Upper Carboniferous Chełmiec rhyodacite laccolith. They are dominated by galena, sphalerite (with Cd up to 0.04 apfu) and tetrahedrite group minerals (TGM). Four generations of the TGM were distinguished according to textural features and Ag content: (1) low-Ag tetrahedrite-(Zn) (Ag: 0.22–0.6 apfu), (2) Ag-enriched tetrahedrite-(Zn) and Ag-enriched tetrahedrite-(Fe) (Ag: 0.71–1.45 apfu), (3) members of the freibergite series: “freibergite-(Fe)” and “freibergite-(Zn)” (Ag: 3.21–3.48 apfu; Hg: up to 0.75 apfu), (4) member of the “freibergite-(Fe)” series (Ag: 5.32–5.78 apfu). Several elongated inclusions of Ag-bearing sulphosalts within galena crystals were observed (members of the series “freibergite-(Fe)” and “freibergite-(Zn)”, pyrargyrite and polybasite). These polymetallic silver-bearing ores were mined in Boguszów from the 15th to the 19th century. Additionally, small grains of cobalt-enriched löllingite and gersdorffite were observed, which were formed from fluids sourced from the ultramafic basement. The textural characteristics of the ore, the mineral paragenesis and the chemical composition of individual ore minerals indicate low-temperature crystallization conditions.

scholarly journals ORE MINERALS FROM KUROKO TYPE DEPOSIT OF TOYA-TAKARADA MINE, HOKKAIDO, JAPAN

2016 ◽  
Vol 11 (2) ◽  
pp. 103-115
Author(s):  
Euis Tintin Yuningsih, ST., MT., Ph.D
Keyword(s):  
Middle Miocene ◽  
Silver Content ◽  
Quantitative Chemical Analysis ◽  
Sulfur Fugacity ◽  
Fine Grained ◽  
Sulfide Ore ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Small Grains ◽  
Homogenization Temperatures

Toya-Takarada mine is Au- and Ag-rich Kuroko-type deposit located in Takarada, Toya-mura, southwest Hokkaido, Japan. The deposits were hosted in rhyolitic tuff and mudstone of Middle Miocene age. Ore samples of fine-grained black ore, vuggy black-yellow ore, granular vuggy black ore, quartz-sulfide ore and massive quartz-barite ore were studied to identify the ore minerals association in the Toya-Takarada mine. The ore minerals are dominated by sphalerite, galena, chalcopyrite and pyrite with fewer amounts of electrum, tetrahedrite-tennantite, and other sulfosalt minerals with secondary mineral of covellite.The quantitative chemical analysis of ore minerals by EPMA indicated that FeS contents in sphalerite is low (0.3-1.2 mol.%) in all kinds of ore samples. Small grains of electrum as inclusions in pyrite are identified in vuggy black-yellow ore with Ag content around 32-33 atm %.In general, the silver minerals in Kuroko-type deposits occurred mainly in the black and yellow ores zone dominantly composed of sphalerite, galena, pyrite, chalcopyrite and barite as a form of electrum and/or argentian tetrahedrite-tennantite series. Thus, the massive quartz-barite ore sample of Toya-Takarada mine are also contain some rare silver sulfosalt minerals such as proustite, Cu-rich pearceite, geocronite-jordanite and fizelyite. Those minerals were found together in association with sphalerite. It seems that sphalerite was crystallized first followed by proustite and Cu-rich pearceite, then geocronite-jordanite and fizelyite are crystallized later.Sphalerites from quartz-sulfide ore of Toya-Takarada contain some fluid inclusions and measured homogenization temperatures are in the range of 164-247°C (av. 208°C) with salinity ranging from 1.9 to 4.7 wt.% NaClequiv. (av. 3.9 wt.% NaClequiv.). The mineral assemblage, iron content in sphalerite and silver content in electrum were indicated that sulfur fugacity was slightly higher during ore mineralization in Toya-Takarada mine.   

Volume preserving immersed boundary methods for two-phase fluid flows

2011 ◽  
Vol 69 (4) ◽  
pp. 842-858 ◽  
Author(s):  
Yibao Li ◽  
Eunok Jung ◽  
Wanho Lee ◽  
Hyun Geun Lee ◽  
Junseok Kim
Keyword(s):  
Fluid Flows ◽  
Immersed Boundary ◽  
Immersed Boundary Methods ◽  
Two Phase ◽  
Boundary Methods ◽  
Phase Fluid ◽  
Volume Preserving

scholarly journals Picking up the hydrothermal whisper at Ischia Island in the Covid-19 lockdown quiet

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mariarosaria Falanga ◽  
Paola Cusano ◽  
Enza De Lauro ◽  
Simona Petrosino
Keyword(s):  
Pressure Fluctuations ◽  
Hydrothermal Fluids ◽  
Shallow Aquifer ◽  
Two Phase ◽  
Spectral Content ◽  
Ischia Island ◽  
Continuous Noise ◽  
Organ Pipes ◽  
Source Signals ◽  
Phase Fluid

AbstractIn this paper, we analyse the seismic noise at Ischia Island (Italy) with the objective of detecting the hydrothermal source signals taking advantage of the Covid-19 quiescence due to lockdown (strong reduction of anthropogenic noise). We compare the characteristics of the background noise in pre-, during and post-lockdown in terms of spectral content, energy release (RMS) and statistical moments. The continuous noise is decomposed into two independent signals in the 1−2 Hz and 2−4 Hz frequency bands, becoming sharpened around 1 Hz and 3 Hz respectively in lockdown. We propose a conceptual model according to which a dendritic system of fluid-permeated fractures plays as neighbour closed organ pipes, for which the fundamental mode provides the persistent whisper and the first higher mode is activated in concomitance with energy increases. By assuming reasonable values for the sound speed in low vapor–liquid mass fraction for a two-phase fluid and considering temperatures and pressures of the shallow aquifer fed by sea, meteoric and deep hydrothermal fluids, we estimate pipe lengths in the range 200–300 m. In this scheme, Ischia organ-like system can play both continuous whisper and transients, depending on the energy variations sourced by pressure fluctuations in the hydrothermal fluids.

scholarly journals Functional Estimation of Plate Type Evaporator with Communication Wick for Two-Phase Fluid Loop in Space

2006 ◽  
Vol 72 (719) ◽  
pp. 1781-1788
Author(s):  
Haruo KAWASAKI ◽  
Ryoji IMAI ◽  
Kanji OHONISHI ◽  
Kengou OHKUBO ◽  
Terushige FUJII
Keyword(s):  
Two Phase ◽  
Functional Estimation ◽  
Phase Fluid ◽  
Plate Type
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