gold and amphibolite

  • All about skarns

    All about skarns

    Oxidized Gold Skarns Whereas the "classic" gold skarn deposit is characterized by low garnet:pyroxene ratios, hedenbergitic pyroxene, and abundant sulfides dominated by pyrrhotite and arsenopyrite, several skarns have been mined for gold that have a very different mineralogy and mineralization style.

  • Relative timing of emplacement of an Archean lodegold ...

    Relative timing of emplacement of an Archean lodegold ...

    The Eastmain River deposit is located within the Archean Upper Eastmain River greenstone belt, approximately 320 km north of Chibougamau. The regional stratigraphy is dominated by ultramafic to felsic volcanosedimentary units and aluminous sedimentary strata that have undergone amphibolitegrade regional deposit is hosted by a narrow brittle–ductile shear zone striking ...

  • Amphibolite Facies definition of Amphibolite Facies by ...

    Amphibolite Facies definition of Amphibolite Facies by ...

    Amphibolite Facies synonyms, Amphibolite Facies pronunciation, Amphibolite Facies translation, English dictionary definition of Amphibolite Facies. n. A metamorphic rock composed chiefly of amphibole and plagioclase feldspar and having little or no quartz. am·phib′o·lit′ic adj. n a metamorphic rock...

  • Gold, Mining and Prospecting: Orogenic Gold Deposits

    Gold, Mining and Prospecting: Orogenic Gold Deposits

    Over the last century this class of gold deposit has been known by many different names like mesothermal gold deposits, metamorphic gold, goldonly, lode gold, shearzone hosted, structurally controlled and a host of other names including greenstonehosted and turbidite hosted deposits. To cover this mélange of varying names the term "Orogenic Gold" has been proposed by (Grove et al) in ...

  • Metamorphism in Archaean greenstone belts: calculated ...

    Metamorphism in Archaean greenstone belts: calculated ...

    For mafic and ultramafic sequences, the composition of fluids released at upper greenschist to lower amphibolite facies conditions for the necessary relatively hot geotherm corresponds to those inferred for greenstone gold deposits (X CO2 = –).

  • amphibolite | AZGS Document Repository

    amphibolite | AZGS Document Repository

    The suite includes eclogite, amphibolite, clinopyroxenite, garnet websterite, granulite, and spinel peridotite (Nealey and Sheridan 1989). Xenocrysts of pyroxene, amphibole, plagioclase and quartz are common in the latite (Tyner 1984), and have been interpreted as .

  • GemHunter's Guide to Gold and Diamonds in Montana

    GemHunter's Guide to Gold and Diamonds in Montana

    These intrusives enclose xenoliths from the Precambrian basement, upper crust (schist, gneiss, amphibolite), lower crust (granulite, mafic granulite, amphibolite), and the upper mantle (spinel peridotite, dunite, garnet peridotite, garnet megacrysts), as well as kimberlitic indicator mineral xenocrysts. ... While seaching for diamonds and gold ...

  • Amphibolite Fire Mountain Gems and Beads

    Amphibolite Fire Mountain Gems and Beads

    Bead, amphibolite (natural), 7x4mm8x7mm handcut faceted rondelle with hole, B grade, Mohs hardness 5 to 6. Sold per 8inch strand.

  • Marymia: an Archean, amphibolite facieshosted, orogenic ...

    Marymia: an Archean, amphibolite facieshosted, orogenic ...

    Structural timing and temperature of formation of alteration and ore minerals support deposition of gold during late peak amphibolitefacies metamorphism from neutral to alkaline (pH = 56), moderately oxidising (log f(O2)approximate to2122) and CO2bearing (X(CO2)approximate ) fluids.

  • on Composition of Greenstone Amphibolite

    on Composition of Greenstone Amphibolite

    were done in gold capsules in internally heatedpressurevessels (7). Weranfoursets ofexperiments, twoin the closed system (1 and 3 kbar, 9000 to 1000°C, no water added) and two watersaturated (1 and 3 kbar, 8500 to 1000°C, wateradded). In the watersaturated experiments, distilled water wastypically 20to 30weightpercentofthe charge ...

  • Donnybrook Goldfield (Hunters Venture mine), Donnybrook ...

    Donnybrook Goldfield (Hunters Venture mine), Donnybrook ...

    Donnybrook Goldfield (Hunters Venture mine), DonnybrookBalingup Shire, Western Australia, Australia : Richard Hunter discovered gold 6 kilometres southwest of Donnybrook in 1897. Fred Camilleri purchased a majority stake in the lease, and a company called Donnybrook Goldfields Ltd was floated in ...

  • Gold in California

    Gold in California

    May 31, 2013· California was a rich state in gold until politics ended much of the mining and exploration. The state could make a comeback in gold and diamond mining, but would require a positive political arena favorable to exploration.

  • Angels Camp, Gold Districts of California

    Angels Camp, Gold Districts of California

    Gold Districts of California. ANGELS CAMP. Location. This district is in southwest Calaveras County in the vicinity of the town of Angels Camp and Altaville. It is an important part of the Mother Lode belt and lies between the San Andreas district to the northwest and the Carson Hill district to the southeast.

  • Gold Prospecting Prospector's Guide to Finding Gold

    Gold Prospecting Prospector's Guide to Finding Gold

    Gold Prospectors Guide to lode placer gold. Facts on how where to find gold in nature. The author found hundreds of gold anomalies as well as an entirely new gold district (Rattlesnake Hills, Wyoming) and was on the discovery team of the 41 million ounce Donlin Creek gold deposit in Alaska.

  • Primary alteration and geochemical dispersion haloes of ...

    Primary alteration and geochemical dispersion haloes of ...

    Aug 01, 2001· Widespread orogenic gold deposits are hosted by practically all rock types over the range of metamorphic grades in the Archaean Yilgarn Craton, Western Australia. They are normally located in second or thirdorder structures, most commonly near crustal to regionalscale deformation zones, in brittle, brittle–ductile and ductile deformational environments.

  • Xavier University of Wisconsin–Madison

    Xavier University of Wisconsin–Madison

    The AMB deposit is located in a narrow sequence of highly deformed sequence of mafic metavolcanics and clasticchemical metasediments, tightly squeezed between two syntectonic granitic batholiths, and metamorphosed to amphibolite facies. The gold mineralization is closely associated with centimeter wide quartz veins containing disseminations ...

  • Montana Gold The GOLD HUNTER

    Montana Gold The GOLD HUNTER

    The district is underlain by Archean gneiss interbedded with iron formation, marble, graphitic schist and amphibolite intruded by pegmatite and ultramafic dikes. Gold was found in place in northeasttrending shear zones associated with pyritiferous veins and breccias .

  • 2635 Ma amphibolite facies gold mineralisation ... DeepDyve

    2635 Ma amphibolite facies gold mineralisation ... DeepDyve

    Oct 25, 2007· Read "2635 Ma amphibolite facies gold mineralisation near a terrane boundary (suture?) on Storø, Nuuk region, southern West Greenland, Precambrian Research" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.

  • Stream Sediment Geochemical Exploration for Gold in the ...

    Stream Sediment Geochemical Exploration for Gold in the ...

    Stream Sediment Geochemical Exploration for Gold in the KazdaÛ Dome in the Biga Peninsula, Western Turkey HƒSEYÜN YILMAZ Dokuz Eyl l ƒniversitesi, M hendislik Fak ltesi, Jeoloji M hendisliÛi Bıl m, Buca, TR—35160 Üzmir, Turkey

  • Geologic units containing Schist USGS

    Geologic units containing Schist USGS

    Hanover Schist coarse to finegrained feldspathic biotitesericitequartzmuscovite schist, commonly containing staurolite, garnet, and locally sillimanite in northeastern outcrop areas includes zones of aluminous graphite schist, hornblende quartzite, garnet quartzite, and rare amphibolite. Schist commonly retrograded to sericitegarnet ...

  • Rhea | Columbus Gold Corporation

    Rhea | Columbus Gold Corporation

    The prospected gold(copper)(silver) vein structural zone occurs on the north edge of a prominent circular topographic feature. Locally observed potassic alteration (sericite and Kfeldspar), amphibolite grade contact metamorphism and copper sulfide minerals in veins are indicative of an intrusiverelated mineralized system.

  • Geochemical reconnaissance of the Carroll County Gold Belt ...

    Geochemical reconnaissance of the Carroll County Gold Belt ...

    The gold deposits in the Carroll County gold belt and the southwestern part of the Dahlonega gold belt are in interlayered metasedimentary and metavolcanic rocks of Late Proterozoic to early Paleozoic age. These rocks are in several thrust sheets that form the southwest continuation of the Blue Ridge thrust stack. The rocks are now mostly mica gneiss and schist, graphitic schist and phyllite ...