Gold-bearing, pre-orogenic laminated quartz veins with quartz-sericite-pyrite alteration halos (the Au1 hydrothermal event) account for the majority of gold endowment and are overprinted by (1 ...
Fimiston-style, shear zone-hosted gold mineralisation. Shear zone-hosted gold is typically associated with irregular, deformed, quartz-carbonate veins, shear-parallel foliation and sulphide stringers (Fig. 5a, b). More intensely sheared and deformed rocks commonly have higher gold grades, with local grades of up to 500 g/t Au recorded in ...
The Berners Bay district at the north end of the Juneau gold belt, southeast Alaska, contains a series of structurally controlled mesothermal gold-bearing quartz …
The silicified shear zone of the pillow metabasalt rocks, however, is richer in SiO 2 (>80%) and contains up to 45 ppm Au. Gold is observed as fine grains ( ca 0.3 …
Discoveries of gold mineralization hosted in the Cretaceous metamorphic terrains such as the Awak Mas gold deposits in South Sulawesi (Ernowo et al., 2019;Hakim et al., 2018;Tuakia et al., 2018 ...
Abstract. Many mesothermal gold-quartz deposits are localized along high-angle reverse or reverse-oblique shear zones within greenstone belt terrains. …
REE composition of the carbonates of the auriferous quartz carbonate veins (QCVs) of the Neoarchean Ajjanahalli gold deposit, Chitradurga schist belt, Dharwar Craton, is characterized by U-shaped ...
At Nagambie, gold mineralisation is associated with quartz stringers and stockwork veining near the crest of the east-trending Mine Hill Anticline in Early …
metabasalt/amphibolite represents a possible regional. ... quartz veins and stringers. Tremolitic ultramafic-hosted ... It comprises an orogenic gold deposit hosted by the amphibolite-facies Serra ...
Sabet and Bordonosov (1984) classified gold deposits in Egypt into three formations namely gold-sulphide formation, skarn gold-ferruginous quartzite formation and gold quartz formation. Although this classification is the first actual attempt at classifying gold deposits in Egypt, it ignores the tectonic setting of host rocks, as well as the ...
• Quartz veins and stringers, • Foliations and lineation, • Limonite and chloritic alteration in shears; • Sericitization only present at feldspar porphyry to meta-basalt transition; • Fresh and unaltered lithologies also identified. The gold-copper mineralization at May claims is hosted in hydrothermally fractured, jointed, sheared zones
Metabasalts surrounding the metasediment-hosted base metal deposit at Mount Isa have been modified by metamorphism, polyphase deformation, and ... facies metamorphism and deformation and is widely distributed in flow-top breccias and as halos around synmetamorphic quartz-calcite veins. ... where mixing of metabasalt-derived …
According to Harris (1961), the majority of known gold quartz vein deposits are epigenetic, hosted in carbonate-altered TAJE_A_831773.3d (TAJE) 15-01-2014 11:23 7 Downloaded by [University of Western Australia] at …
The aim of this study was to develop a comprehensive technology for the utilization of tailings from quartz vein-hosted gold deposits. We investigated the recovery potential and separation process for gold, feldspar, and quartz from tailings samples collected from the Jinqu gold mine in Henan province, China. The sequence of the …
• Quartz veins and stringers, • Foliations and lineation, • Limonite and chloritic alteration in shears; • Sericitization only present at feldspar porphyry to meta-basalt transition; • …
The Bronzewing gold deposit is hosted within the middle to upper greenschist facies, tholeiitic metabasalt of the Yandal greenstone belt within the Archean Yilgarn craton. ... at the Klipwal Gold Mine is confined to laminated quartz–carbonate lodes, stringers, and associated alteration in sandstone and siltstone of the … Expand. …
The study area is a part of Western Lode system of GSB best exposed near Hosur is hosted by pillow basalts and andesite consists of both free milling and sulphide hosted gold. Sheared metabasalt zone shows contact with narrow bands of quartz porphyry with occurrence of free gold in quartz.
Gold-bearing veins within the Liese zone of the Pogo deposit display a two-stage evolutionary history that records temporal variation in kinematics, fluid chemistry and temperature. Several stacked shallow northwest-dipping shear veins are developed at Pogo, and collectively comprise the Liese Zone. Veins consist of: (1) early, narrow …
The Berners Bay district at the north end of the Juneau gold belt, southeast Alaska, contains a series of structurally controlled mesothermal gold-bearing quartz veins. The 106 Ma Jualin Diorite, which intrudes metabasalt of the Wrangellia terrane, hosts most of the > 2 Moz of gold resources.
The Paleo-Mesoproterozoic North Singhbhum Mobile Belt (NSMB) is a fold-thrust belt typically found in a collisional setting and is well known for hosting gold mineralisation. A study carried out in the northern part of NSMB depicts varieties of acid volcanic rocks along with mica schist, ferruginous cherty quartzite, black shale, and …
Different from the typical orogenic-gold deposits of the Yilgarn Craton (Groves et al., 1998), the Karari gold deposit is an example of disseminated deposit associated with quartz …
The boron isotope compositions of metabasalt-hosted tourmaline show a bimodal distribution with peak δ11B values at about −2‰ and +6‰. The wide range and bimodal distribution of boron isotope ratios in tourmaline require an origin from at least two isotopically distinct fluid sources, which entered the hydrothermal system separately and ...
This study investigates the structural control of the numerous gold occurrences in the southern part of the Barberton Greenstone Belt in the Malolotja and Steynsdorp areas. The gold-bearing event distribution is studied using field structural geology associated with a petrological and microstructural analysis. Three major tectonic …
PRXF is a method for determining elements in a substance and their relative amounts through qualitative and quantitative analyses (Potts and West, 2008;Hall et al., 2014;Zhuo and Ji, 2003).
Gold quartz vein deposits in the Wattle Gully mine arefault-related structures developed in a low-grade metamorphosed Ordovician quartz-rich ... V. J. Wall, T. F. Potter; Structural and geochemical controls on the development of turbidite-hosted gold quartz vein deposits, Wattle Gully Mine, central Victoria, Australia. Economic Geology 1995 ...
Quartz-pebble-conglomerate gold deposits represent some of the largest gold depositories in the world; in fact, the Witwatersrand Basin represents the largest resource of produced gold in the world (for example, Frimmel, 2002, 2008; Frimmel and Minter, 2002). Grains of native gold are found within coarse-grained sediment beds, either directly
Greenstones may also contain Na-rich plagioclase (albite), quartz, carbonates, and zeolites. The photo below in Figure 8.65 shows a typical greenstone outcrop in northern Minnesota. Figures 8.34 and 8.35, earlier in this chapter, showed other examples. ... Figure 8.66, below, shows a greenschist from the Homestake Gold Mine in …
Alto reports the gold mineralisation at this target is hosted within quartz reefs and has not been adequately tested by drilling. ... about 5km north of Vanguard on the eastern limb of the Sandstone Greenstone Belt within an area of folded and sheared metabasalt, metadolerite, chert, and BIF. ... is defined over an area of about 1.5km by …
Gold occurs with a sulfide assemblage of pyrite, arsenopy-rite, pyrrhotite, chalcopyrite, and sphalerite in quartz or quartz–carbonate veins located in steeply dipping brittle– ductile shear zones. Fluid inclusion studies and geother-mometry calculations from ore and alteration assemblages indicate a temperature range of 350° to 500°C for ...
Gold mineralization in the Klipwal Shear Zone (KSZ) at the Klipwal Gold Mine is confined to laminated quartz–carbonate lodes, stringers, and associated alteration in sandstone and siltstone of the Delfkom Formation in the upper Mozaan Group of the Mesoarchaean Pongola Supergroup. The moderately dipping brittle–ductile KSZ strikes …
Iron and copper are concentrated in the cores of the feeders with zinc and lead, silver, gold and arsenic, and barium becoming increasingly dispersed away from the centers of hydrothermal activity.Distinct delta 34 S variations exist between vein stages within the stringer and stringer envelope zones. The main base metal-rich stage 2B …
Highlights δ 13 C of quartz carbonate veins of two Archaean orogenic gold deposits, Dharwar craton, India are examined. δ 13 C data of these venis match those of mantle/magmatic derived carbonates. The age of gold mineralization overlaps with age of some of the granites in the craton. Mineralizing fluids were either derived from mantle or …
The metamorphic rocks of the Archean Gwanda greenstone belt of southwestern Zimbabwe consist of mafic to felsic volcanics with intercalated sedimentary units among which banded iron-formations ...
The intensity of metamorphism and the vigor of metamorphic transformation are expressed by the term metamorphic grade.If for instance a granitic pluton intrudes sedimentary rocks, the resulting contact metamorphic aureole will contain rocks of higher grade close to the contact of the granite (heat source) and rocks of low grade at greater distance from the …
The Callion gold-quartz veins are hosted by metabasalts, interflow sediments and acid metatuffs within the Archaean Norseman-Wiluna greenstone belt. ... It is composed of several discrete quartz veins up to 6 m thick and/or numerous quartz stringers within sheared metabasalt. When fresh, the quartz is milky-white, but near …
1. Introduction. Epigenetic Archean orogenic gold deposits occur in quartz carbonate veins (QCVs) or as disseminations in crustal scale shear zones (Groves et al., 1988, 2003).So far, more than 100 deposits of this nature have been reported in different parts of the world (Goldfarb et al., 2005).From the field, petrographic, geochemical and …
The latter occur in quartz veins (hosted in metabasalt) that form lodes striking dominantly in NW-SE direction (Figs. 1 c, 2 e). This is also the strike of the magnetic foliation in the host-rock metabasalts ( Fig. 2 d), which is interpreted as syntectonic to D1/D2 (NE-SW shortening; Mondal and Mamtani, 2013, Mondal and Mamtani, 2014 ).
At Bombana, gold-bearing quartz-veins are hosted by the Pompangeo metamorphic complex. Sheared, segmented veins vary in thickness from 2 cm to 2 m. Gold is mainly present in the form of 'free ...
The silicified shear zone of the pillow metabasalt rocks, however, is richer in SiO 2 (>80%) and contains up to 45 ppm Au. Gold is observed as fine grains (ca 0.3 mm) and minute blebs (20-0.5 µm) intergrown with quartz or as
The lode gold deposits of southern Nova Scotia are considered to be one of the classic occurrences of turbidite-hosted gold mineralization (Malcolm 1929; Kontak et al. 1990). These deposits consist of concordant and discordant gold-bearing quartz veins hosted by meta-sandstones and metasiltstones of the Lower Paleozoic Meguma Group.
