scholarly journals Magmatic-Hydrothermal Processes of Vein-Type Haman-Gunbuk-Daejang Copper Deposits in the Gyeongnam Metallogenic Belt in South Korea

2021 ◽  
Vol 9 ◽  
Author(s):  
Tong Ha Lee ◽  
Jung Hun Seo ◽  
Bong Chul Yoo ◽  
Bum Han Lee ◽  
Seung Hee Han ◽  
...  

Haman, Gunbuk, and Daejang deposits are neighboring vein-type hydrothermal Cu deposits located in the SE part of the Korean Peninsula. These three deposits are formed by magmatic-hydrothermal activity associated with a series of Cretaceous granodioritic intrusions of the Jindong Granitoids, which have created a series of veins and alterations in a hornfelsed shale formation. The copper deposits have common veining and alteration features: 1) a pervasive chlorite-epidote alteration, cut by 2) Cu-Pb-Zn-bearing quartz veins with a tourmaline-biotite alteration, and 3) the latest barren calcite veins. Chalcopyrite, pyrite, and pyrrhotite are common ore minerals in the three deposits. Whereas magnetite is a dominant mineral in the Haman and Gunbuk deposits, no magnetite is present, but sphalerite and galena are abundant in the Daejang deposit. Ore-bearing quartz veins have three types of fluid inclusions: 1) liquid-rich, 2) vapor-rich, and 3) brine inclusions. Hydrothermal temperatures obtained from the brine inclusion assemblages are about 340–600, 250–500, and 320–460°C in the Haman, Gunbuk, and Daejang deposits, respectively. The maximum temperatures (from 460 to 600°C) recorded in the fluid inclusions of the three deposits are higher than those of the Cu ore precipitating temperature of typical porphyry-like deposits (from 300 to 400°C). Raman spectroscopy of vapor inclusions showed the presence of CO2 and CH4 in the three deposits, which indicates relatively reduced hydrothermal conditions as compared with typical porphyry deposits. The Rb/Sr ratios and Cs concentrations of brine inclusions suggest that the Daejang deposit was formed by a later and more fractionated magma than the Haman and Gunbuk deposits, and the Daejang deposit has lower Fe/Mn ratios in brine inclusions than the Haman and Gunbuk deposits, which indicates contrasting redox conditions in hydrothermal fluids possibly caused by an interaction with a hosting shale formation. In brines, concentrations of base metals do not change significantly with temperature, which suggests that significant ore mineralization precipitation is unlikely below current exposure levels, especially at the Haman deposit. Ore and alteration mineral petrography and fluid inclusions suggest that the Haman deposit was formed near the top of the deep intrusion center, whereas the Gunbuk deposit was formed at a shallower intrusion periphery. The Daejang deposit was formed later at a shallow depth by relatively fractionated magma.

2019 ◽  
Vol 122 (2) ◽  
pp. 173-186
Author(s):  
F. Mees ◽  
R. Adriaens ◽  
A. Delgado-Huertas ◽  
D. Delvaux ◽  
P. Lahogue ◽  
...  

Abstract Tectonic fractures in Palaeozoic strata of the Kinshasa area, DR Congo, locally host palygorskite-bearing veins and associated calcite occurrences. The palygorskite deposits are typically massive, with a varying degree of alignment of clay particles, a higher quartz content than the arkose substrate, and a variable amount of smectite (montmorillonite). The associated calcite occurrences are macrocrystalline coatings and infillings, and more fine-grained calcite veins with cataclastic texture. The calcite coatings and infillings formed from solution in earth surface conditions, as recorded by their stable isotope signature. The palygorskite-dominated deposits in the fractures formed at a later stage, in a setting without indications of authigenic mineral formation related to hydrothermal activity or to low-temperature interaction of solutions with the local substrate. The veins most likely formed by vertical infiltration of suspended matter in fractures that extended to a post-Palaeozoic palaeosurface, during or after deposition of palygorskite-bearing Upper Jurassic to Early Cretaceous sediments. This represents an exceptional mode of palygorskite vein development, unrelated to any form of mineral authigenesis that is typically invoked to explain vein-type occurrences of palygorskite and related minerals.


2017 ◽  
Vol 2 (1) ◽  
pp. 48
Author(s):  
Pranayoga Pramumijoyo ◽  
Arifudin Idrus ◽  
I Wayan Warmada ◽  
Kotaro Yonezu

On the basis of the previous studies and reconnaissance survey in the studyarea covering Sangon, Kalirejo, Kokap Sub-district, Kulon Progo Regency, Special Region of Yogyakarta, it reveals some facts of the occurrence of quartz veins with massive, crustiform, comb, drusy cavity, saccharoidal, granular, and reniform/mammillated textures, the appearance of lattice bladed barite and hydrothermal breccia veins. Referring to those characteristics, the deposit type in the study area is interpreted to be low sulfidation epithermal type. This study is aimed to understand and characterize the geological condition, rock and ore geochemistry and the mineralizing fluids. The alteration and ore mineralization are almost observed in entire rock units particularly the intrusive andesite 1. Their formation is controlled by the tension fractures (NW–SE and NE–SW) which associate with sinistral strike slip faults (NE–SW), dilational jog (NNW–SSE), oblique normal fault (WNW–ESE), and predictable normal fault at the NE of study area (NW–SE). The alteration zones are developed to be silica-clay (quartz-illite-kaolinite-kaolinite/smectite), argillic (smectite-illite/smectite), and propylitic (chlorite-calcite±epidote). The precipitationof ore minerals is controlled by boiling, mixing, and wall-rock alteration, and canbe found in the quartz veins (quartz-adularia-sericite) and disseminated in the alteration zones, which their high variability is only can be found in the quartz veins, including pyrite, sphalerite, chalcopyrite, galena, marcasite, and arsenopyrite. Based on the ICPAES measurement of 5 quartz vein samples, the Cu, Zn, Pb, and As grade reach about 5,171 ppm, 8,995 ppm, 6,398 ppm, 34.1 ppm, and 1,010.5 ppm, respectively. Gold is not detected. Fluid inclusion microthermometric analysis shows Th of 242.1–257.6 °C and salinity of 1.57–3.87 wt.% NaCl equiv., which indicate a depth below the paleosurface of 384–516 m, and pressure of 101.7–136.6 bar. The ore deposit in the study area is interpreted to be a deep basemetal low sulfidation epithermal type. Gold might be depleted in this epithermal type.


Author(s):  
Ф.А. Файзиев ◽  
А.Р. Файзиев

Серебро-золоторудный формационный тип минерализации в Таджикистане известен в пределах Табошар-Канджольского рудного узла (Карамазар) и на Памире. В Карамазаре к этому типу относятся месторождения Школьное, Четсу и Караулхона, а на Памире рудопроявления Сассык, Лянгар, Бугучиджилга, Курустык и др. Серебро-золоторудный формационный тип представлен убогосульфидными кварц-золоторудными жилами с высоким содержанием серебра. Рудные минералы представлены пиритом, тетраэдритом, халькопиритом, пираргиритом, фрейбергитом, миаргиритом, самородным золотом, электрумом и кюстелитом. Формационными особенностями этого типа являются предрудная пропилитизация, синрудная березитизация, многостадийный характер минерализации, простой минеральный состав, крайне неравномерное распределение серебра и золота, а также близповерхностное образование золота и его низкопробность. Продуктивное оруденение в них образовалось при сравнительно низких температурах (300–150ο) и давлениях (500 бар и ниже). Silver-gold ore-formation type mineralization in Tajikistan known within Taboshar-Kanjol – ore unit (Karamazar) and the Pamirs. The most known deposits KaramazarScholnoe, Chetsy and Karaulhona and the Pamirs to this type of ore can be attributed Sassyk, Langar, Buguchidzhilga, Kurustyk. Silver-gold ore-formation type is represented by poorly-high silver sulfide-quartz veins of gold mining. The ore minerals are pyrite, tetrahedrite, chalcopyrite, pyrargyrite, freibergite, miargyrite, native gold, electrum and kyustelitе. Formational peculiarities of this type are pre-ore propylitization, sin-ore beresitization, multi-stage nature of the mineralization, simple mineral composition, extremely uneven distribution of silver and gold, as well as subsurface formation of gold and its sleaze. Productive mineralization formed there in at relatively low temperatures (300–150ο) and pressures (500 bar or less).


Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1093
Author(s):  
Evgeny G. Sidorov ◽  
Andrey A. Borovikov ◽  
Nadezhda D. Tolstykh ◽  
Daria S. Bukhanova ◽  
Galina A. Palyanova ◽  
...  

Microthermometry study of fluid inclusions in quartz veins of the Maletoyvayam deposit (Koryak Highland, Russia) was carried out. This epithermal gold deposit contains unique Au compounds including maletoyvayamite, which has not been reported anywhere else. Two paragenetic mineral associations (pyrite-quartz and maletoyvayamite-quartz) with quartz of different generations corresponding to different pulses were also described. Only early generations of quartz (Q1) include ore minerals: pyrite for the first mineral assemblage, and in Au-bearing minerals, sulfosalts, bismuthinite, and others—for the second assemblage. A study on fluid inclusions in quartz showed a salinity (mainly NaCl + KCl) range from 0.2 to 4.3 wt.% NaCl eq., increasing from the first mineral association to the second due to boiling fluids. The obtained temperature variations for quartz crystallization were 295–135 °C, the fluid pressure ranged from 79 to 4 bar. On the other hand, the range of conditions obtained for the gold productive ore association is more narrow: salinity of the fluid inclusions is 4.3 wt.% NaCl eq., the temperatures vary from 255 °C to 245 °C, and the pressure from 39 to 32 bar. These physicochemical characteristics of the Maletoyvayam ore deposit greatly coincide with other HS-type epithermal deposits; however, within the Central Kamchatka Volcanic Belt it is so far the only deposit of this type reported.


Minerals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 285 ◽  
Author(s):  
Yong-Gang Sun ◽  
Bi-Le Li ◽  
Feng-Yue Sun ◽  
Ye Qian ◽  
Run-Tao Yu ◽  
...  

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.


2021 ◽  
Vol 9 (1) ◽  
pp. 19
Author(s):  
Ngozi-Chika C.S ◽  
Olorunyomi A. E. ◽  
Echetema H. N. ◽  
Ibrahim O.I

Geochemical mapping using stream sediments from MRDB, north-central, Nigeria was undertaken towards obtaining multivariate association patterns reflecting the presence of ore mineralization in Lokoja region. The area is underlain by Precambrian crystalline rocks within the Benin-Nigeria Shield and clastic sedimentary rocks of Bida Basin (one of Nigeria inland sedimentary basins). The basement crystalline rocks have been known as a source of ore minerals in Nigeria. The major lithological units are cut by the Meme river watershed which have deposited in their tributaries, large quantities of alluvial and eluvial deposits formed during an extensive period of weathering and surficial processes. The PC analysis was performed on clr-transformed of Meme sediment geochemical compositional data of selected ore forming elements in the hope of obtaining geochemical information that could elucidate on the inferred ore mineralization of the region. The eight PCs explain about 93% of the total variance. The positive and negative loadings of PCs indicated the presences of oxides, sulphides, REEs and gems mineralisation in the region. Further interrogation of Spearman correlation of ilr transformed data with respect to the PC loadings indicated  well developed relationship between Sr and V (0.55), Mn and Pb (0.89), Mn and Ta (0.77), Mn and Nb (0.78), Nb vs Ta (0.98), Rb and Cr (0.59), In and As (0.64), Pb and Ga (0.78), Sb and Au (0.52), Ba and Cr (0.50). The elemental association suggests that they are either indicator of their own mineralization or are suitable pathfinders to pertinent minerals in Lokoja region. The negative correlation between Fe with other ore elements indicated that the Fe is from both proximal and dextral sources probably due to many Fe formations and mineralisation (goethite, haematite± siderite – bearing sedimentary ironstone formations in the region). The high Spearman correlation coefficients between Mn, Nb and Ta inferred that these ore elements are from the proximal sources because they are reliable pathfinders to pertinent oxides mineralisation in the region. Inferred proximal mineralisation in the region include beryl, topaz, columbite, quartzofeldspathic and quartz veins with anomalous concentration of Au as well as industrial minerals which are artisanally mined in places for industrial purposes. 


2021 ◽  
Vol 54 (1E) ◽  
pp. 1-18
Author(s):  
Toe Oo ◽  
Agung Harijoko ◽  
Lucas Setijadji

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.


Mineralogia ◽  
2012 ◽  
Vol 43 (3-4) ◽  
pp. 199-212
Author(s):  
Łukasz Karwowski ◽  
Marek Markowiak

AbstractIn one small mineral vein in core from borehole 144-Ż in the Żarki-Kotowice area, almost all of the ore minerals known from related deposits in the vicinity occur. Some of the minerals in the vein described in this paper, namely, nickeline, hessite, native silver and minerals of the cobaltite-gersdorffite group, have not previously been reported from elsewhere in the Kraków-Lubliniec tectonic zone. The identified minerals are chalcopyrite, pyrite, marcasite, sphalerite, Co-rich pyrite, tennantite, tetrahedrite, bornite, galena, magnetite, hematite, cassiterite, pyrrhotite, wolframite (ferberite), scheelite, molybdenite, nickeline, minerals of the cobaltitegersdorffite group, carrollite, hessite and native silver. Moreover, native bismuth, bismuthinite, a Cu- and Ag-rich sulfosalt of Bi (cuprobismutite) and Ni-rich pyrite also occur in the vein. We suggest that, the ore mineralization from the borehole probably reflects post-magmatic hydrothermal activity related to an unseen granitic intrusion located under the Mesozoic sediments in the Żarki-Pilica area.


Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 165
Author(s):  
Gabriella B. Kiss ◽  
Zsolt Bendő ◽  
Giorgio Garuti ◽  
Federica Zaccarini ◽  
Edit Király ◽  
...  

Quartz from the stockwork zone of various Cyprus type volcanogenic massive sulfide deposits (Boccassuolo, Reppia, Campegli, Bargone and Vigonzano) from the unmetamorphosed, Jurassic Northern Apennine ophiolites was studied in order to provide details on the submarine hydrothermal conditions and the characteristics for ore formation. Our detailed SEM-CL investigation of quartz contributed to a robust characterization and interpretation of primary fluid inclusions and microthermometry data. SEM-CL imaging was also useful for reconstructing the consecutive steps of quartz precipitation. The determination of trace element contents according to growth zoning in quartz by LA-ICP-MS constrained the compositional variations of parent fluids during the hydrothermal activity. A continuously cooling fluid regime characterized each studied volcanogenic massive sulfide (VMS) occurrence although the minimum formation temperatures were different (Bargone: 110–270 °C; Boccassuolo: 60–360 °C; Campegli: 110–225 °C; Reppia: 50–205 °C; Vigonzano: 260–330 °C), the range of temperature most probably depends on the original position of sampling in relation to the centers of the hydrothermal systems. Compositional changes are reflected by variations in the methane content (0.13–0.33 mol/kg) and salinity (2.6–9.3 NaCl equiv. wt. %) in the fluid inclusions of quartz and calcite as well as a changeable Al content (11–1526 ppm) in quartz. This study demonstrates that the combined use of SEM-CL imaging and LA-ICP-MS analyses, coupled with fluid inclusion microthermometry, can constrain the different fluid conditions of ore forming and the barren stages of evolving submarine hydrothermal systems.


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