Fluid inclusion characteristics of intrusion-related gold mineralization, Tombstone-Tungsten magmatic belt, Yukon Territory, Canada

2001 ◽  
Vol 36 (6) ◽  
pp. 563-582 ◽  
Author(s):  
Timothy Baker ◽  
James Lang
Keyword(s):  
Fluid Inclusion ◽  
Gold Mineralization ◽  
Yukon Territory

Fluid inclusion and stable isotope constraints on the origin of Wernecke Breccia and associated iron oxide – copper – gold mineralization, Yukon

2011 ◽  
Vol 48 (10) ◽  
pp. 1425-1445 ◽  
Author(s):  
Julie A. Hunt ◽  
Tim Baker ◽  
James Cleverley ◽  
Garry J. Davidson ◽  
Anthony E. Fallick ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Fluid Inclusion ◽  
Gold Mineralization ◽  
Fluid Pressure ◽  
Yukon Territory ◽  
Metasedimentary Rocks ◽  
Isotopic Compositions ◽  
Copper Gold ◽  
Oxygen Isotopic ◽  
Hydrothermal Sulfides

Iron oxide – Cu ± Au ± U ± Co (IOCG) mineralization is associated with numerous Proterozoic breccia bodies, collectively known as Wernecke Breccia, in Yukon Territory, Canada. Multiphase breccia zones occur in areas underlain by Paleoproterozoic Wernecke Supergroup metasedimentary rocks and are associated with widespread sodic, potassic, and carbonate alteration assemblages. Fluid inclusion data indicate syn-breccia fluids were hot (185–350 °C) saline (24–42 wt.% NaCl equivalent) NaCl–CaCl2–H2O brines. Estimates of fluid pressure vary from 0.4 to 2.4 kbar (1 kbar = 100 MPa). Carbon and oxygen isotopic compositions of breccia-related carbonates range from ~–11‰ to +1.5‰ (Pee Dee belemnite (PDB)) and –2‰ to 20‰ (Vienna standard mean ocean water (V-SMOW); δ18Owater ~–8‰ to +15‰), respectively. δ13C and δ18O values for host Wernecke Supergroup limestone/dolostone vary from ~–2‰ to 1.6‰ and 12‰ to 25‰, respectively. Sulfur isotopic compositions of hydrothermal sulfides and sulfate vary from ~–12‰ to +13‰ and +8‰ to +17‰ (Cañon Diablo Troilite (CDT)), respectively. Syn-breccia biotite, muscovite, and actinolite have δD and δ18O values of ~–141‰ to –18‰ and +7‰ to +12‰ (V-SMOW; δ18Owater ~7‰ to 11‰), respectively. The Wernecke Breccias and the associated IOCG mineralization appear to have formed from largely nonmagmatic fluids — based on isotopic, fluid inclusion, and geological data. The emerging hypothesis is that periodic overpressuring of dominantly formational/metamorphic water led to repeated brecciation and mineral precipitation. The weight of overlying sedimentary rocks led to elevated fluid temperatures and pressures; fluid flow may have been driven by tectonics and (or) gravity with metals scavenged from host strata.

scholarly journals FLUIDS ASSOCIATED WITH THE CAXIAS MESOTHERMAL GOLD MINERALIZATION, SÃO LUÍS CRATON, NORTHERN BRAZIL: A FLUID INCLUSION STUDY

2000 ◽  
Vol 30 (2) ◽  
pp. 322-326 ◽  
Author(s):  
EVANDRO LUIZ KLEIN ◽  
KAZUO FUZIKAWA ◽  
JAIR CARLOS KOPPE ◽  
MARIA SYLVIA SILVA DANTAS
Keyword(s):  
Fluid Inclusion ◽  
Gold Mineralization ◽  
Fluid Inclusion Study ◽  
Inclusion Study ◽  
Northern Brazil

Hydrothermal zircon and baddeleyite in Val-d'Or Archean mesothermal gold deposits: characteristics, compositions, and fluid-inclusion properties, with implications fortiming of primary gold mineralization

1993 ◽  
Vol 30 (12) ◽  
pp. 2334-2351 ◽  
Author(s):  
Robert Kerrich ◽  
Robert King
Keyword(s):  
Fluid Inclusion ◽  
Gold Mineralization ◽  
Wall Rock ◽  
Gold Deposits ◽  
Southern Volcanic Zone ◽  
Primary Fluid ◽  
Inheritance Model ◽  
Homogenization Temperatures ◽  
Host Rocks

Zircon and baddeleyite occur within quartz–tourmaline veins at four gold deposits in the Val-d'Or district of the Archean Abitibi Southern Volcanic Zone. Host rocks have experienced intense metasomatic enrichment of Zr, Hf, Y, and rare earth elements. The zircons contain primary inclusions of quartz, tourmaline, pyrite, albite, K-mica, scheelite, and gold, and gold occurs in primary fluid inclusions in zircons. Magmatic zircons in host rocks do not have this suite of inclusions; consequently a wall-rock inheritance model for the vein zircons is implausible. Compositionally, the zircons feature pronounced interzone and intergrain variations of Hf, Y, Yb, Th, and U, and sporadic anomalous Ce contents of ~ 1100 ppm, distinct from magmatic counterparts. Two principal types of primary fluid inclusion occur in the vein zircons. Type 1 H2O–CO2 inclusions have low salinities, variable quantities of CO2 and homogenization temperatures of 260–380 °C, and type 2 CO2 rich inclusions contain minor H2O and CH4. The vein zircons coprecipitated at 260–380 °C and ~ 2 kbar (1 kbar = 100 MPa) with coexisting minerals of undisputed hydrothermal origin, such as vein quartz and gold. In the Superior Province, mesothermal gold deposits are related in space and time to translithospheric structures that mark the diachronous accretion of allochthonous subprovinces from north to south between ~ 2710 and 2680 Ma. Consequently, vein zircon ages of ~ 2680 Ma record the primary mineralizing event, whereas aberrantly young ages for rutile, titanite, scheelite, and micas in the same vein systems, that scatter over 2630–2579 Ma, reveal the age of secondary remobilization events.

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