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NARROW
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Africa
-
East Africa
-
Malawi (1)
-
-
Southern Africa
-
Karoo Basin (2)
-
South Africa
-
Bushveld Complex (1)
-
KwaZulu-Natal South Africa (1)
-
Transvaal region (1)
-
-
-
-
Arctic region
-
Svalbard
-
Spitsbergen (1)
-
-
-
Asia
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Arabian Peninsula
-
Saudi Arabia (1)
-
-
Far East
-
China
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Heilongjiang China (1)
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Henan China (1)
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North China Platform (1)
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Qinling Mountains (1)
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Japan
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Kyushu
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Kagoshima Japan (1)
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Korea
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South Korea (1)
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Indian Peninsula
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India
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Maharashtra India
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Mumbai India (1)
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Australasia
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Australia
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Lachlan fold belt (1)
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New South Wales Australia (3)
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Northern Territory Australia (1)
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Queensland Australia
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Cloncurry mining district (1)
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Mount Isa Inlier (1)
-
-
-
-
Canada
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Eastern Canada
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Maritime Provinces
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New Brunswick (1)
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Ontario
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Algoma District Ontario
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Mamainse Point (1)
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-
Batchawana Bay (2)
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Quebec
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Noranda Quebec (1)
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Western Canada
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Alberta
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Athabasca Oil Sands (1)
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British Columbia (1)
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Canadian Cordillera (1)
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Manitoba (1)
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Northwest Territories (1)
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Europe
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Central Europe
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Hungary
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Borzsony Mountains (1)
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Fennoscandia (1)
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Southern Europe
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Iberian Peninsula
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Ossa-Morena Zone (1)
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Spain
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Andalusia Spain
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Seville Spain (1)
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Variscides (1)
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Western Europe
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France
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Central Massif (2)
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Haute-Vienne France (1)
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Limousin (1)
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Ireland
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Galway Ireland
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Galway Granite (1)
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Scandinavia
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Finland
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Pirkanmaa Finland
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Ylojarvi Finland (1)
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United Kingdom
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Great Britain
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Scotland
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Grand Canyon (1)
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Mexico
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Sonora Mexico
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La Caridad Mine (1)
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North America
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Canadian Shield
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Superior Province
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Abitibi Belt (1)
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Great Lakes region (1)
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North American Cordillera
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South America
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Andes
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Central Andes (1)
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Argentina (1)
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Chile (2)
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Peru (1)
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Southern Uplands (1)
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United States
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Arizona (9)
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California
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Salton Sea (1)
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Colorado
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Gilpin County Colorado (1)
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Colorado Plateau (2)
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Midcontinent (1)
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Missouri
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Montana
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Jefferson County Montana (3)
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Park County Montana (1)
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Nevada
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Getchell Mine (1)
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Osgood Mountains (1)
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Mineral County Nevada (1)
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Shoshone Mountains (1)
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New Mexico
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Texas
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Utah (1)
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commodities
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brines (3)
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metal ores
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arsenic ores (1)
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base metals (2)
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bismuth ores (1)
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cobalt ores (2)
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copper ores (27)
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gold ores (19)
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iron ores (4)
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lead ores (3)
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lead-zinc deposits (3)
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molybdenum ores (15)
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nickel ores (3)
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platinum ores (2)
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polymetallic ores (9)
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rare earth deposits (3)
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silver ores (12)
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tin ores (3)
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tungsten ores (7)
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uranium ores (6)
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zinc ores (3)
-
-
mineral deposits, genesis (46)
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mineral exploration (11)
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petroleum (1)
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phosphate deposits (1)
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-
elements, isotopes
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carbon
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C-13/C-12 (4)
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halogens
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bromine (2)
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chlorine
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chloride ion (1)
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iodine (2)
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hydrogen
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D/H (3)
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deuterium (2)
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isotope ratios (7)
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isotopes
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stable isotopes
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C-13/C-12 (4)
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D/H (3)
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deuterium (2)
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He-4/He-3 (1)
-
Nd-144/Nd-143 (1)
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Ne-22/Ne-20 (1)
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O-18 (1)
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O-18/O-16 (8)
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S-34/S-32 (8)
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Sr-87/Sr-86 (1)
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metals
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actinides
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uranium (2)
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alkali metals
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potassium (1)
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sodium (1)
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alkaline earth metals
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strontium
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Sr-87/Sr-86 (1)
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-
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cadmium (1)
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copper (3)
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gold (1)
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iron (1)
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lead (2)
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mercury (2)
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niobium (2)
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platinum group
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platinum ores (2)
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precious metals (1)
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rare earths
-
neodymium
-
Nd-144/Nd-143 (1)
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-
yttrium (2)
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tantalum (1)
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tin (1)
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titanium (2)
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tungsten (2)
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vanadium (1)
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zirconium (1)
-
-
noble gases
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helium
-
He-4/He-3 (1)
-
-
neon
-
Ne-22/Ne-20 (1)
-
-
-
oxygen
-
O-18 (1)
-
O-18/O-16 (8)
-
-
sulfur
-
S-34/S-32 (8)
-
-
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geochronology methods
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Ar/Ar (4)
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K/Ar (2)
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paleomagnetism (1)
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Pb/Pb (1)
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Re/Os (4)
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thermochronology (1)
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U/Pb (6)
-
-
geologic age
-
Cenozoic
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Quaternary
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Pleistocene (1)
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Tertiary
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Neogene
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Miocene
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upper Miocene (1)
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-
-
Paleogene
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Eocene
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lower Eocene (1)
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Oligocene (1)
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Paleocene (2)
-
-
-
-
Mesozoic
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Cretaceous
-
Lower Cretaceous
-
McMurray Formation (1)
-
-
Upper Cretaceous (4)
-
-
Jurassic
-
Lower Jurassic (1)
-
-
Navajo Sandstone (1)
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Triassic
-
Upper Triassic
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Chinle Formation (1)
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Stormberg Series (1)
-
-
-
-
Paleozoic
-
Cambrian
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Upper Cambrian
-
Lamotte Sandstone (1)
-
-
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Carboniferous
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Mississippian
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Redwall Limestone (1)
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-
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Devonian
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Middle Devonian
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Elk Point Group (1)
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Prairie Evaporite (1)
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Ordovician (1)
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Permian
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Ecca Group (2)
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Vryheid Formation (1)
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Whitehill Formation (1)
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Silurian (2)
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upper Paleozoic (2)
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Precambrian
-
Archean
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Blake River Group (1)
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Neoarchean (1)
-
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Eocambrian (1)
-
upper Precambrian
-
Proterozoic
-
Keweenawan (2)
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Mesoproterozoic
-
Belt Supergroup (2)
-
-
Neoproterozoic
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Infracambrian (1)
-
-
-
-
-
-
igneous rocks
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extrusive rocks (1)
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igneous rocks
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carbonatites (2)
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plutonic rocks
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diabase (1)
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diorites
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tonalite (1)
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trondhjemite (1)
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gabbros (1)
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granites (8)
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granodiorites (2)
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quartz monzonite (2)
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syenites
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nepheline syenite (1)
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-
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porphyry (1)
-
volcanic rocks
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andesites (1)
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basalts (1)
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dacites (2)
-
pyroclastics
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ash-flow tuff (1)
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rhyolites (1)
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-
-
-
metamorphic rocks
-
metamorphic rocks
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granulites (1)
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hornfels (1)
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metasomatic rocks
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fenite (1)
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greisen (1)
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skarn (5)
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-
-
-
minerals
-
arsenides
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arsenopyrite (1)
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bismuthides (1)
-
carbonates
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calcite (1)
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-
halides
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fluorides
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cryolite (1)
-
-
-
minerals (1)
-
native elements (1)
-
oxides
-
anatase (1)
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baddeleyite (1)
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cassiterite (1)
-
hematite (3)
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hollandite (1)
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iron oxides (2)
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magnetite (2)
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niobates
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columbite (2)
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euxenite (1)
-
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pitchblende (1)
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rutile (3)
-
tantalates
-
euxenite (1)
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tantalite (1)
-
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titanium oxides (2)
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uraninite (1)
-
-
phosphates
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apatite (3)
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fluorapatite (1)
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monazite (3)
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xenotime (4)
-
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selenites (1)
-
silicates
-
chain silicates
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amphibole group (1)
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pyroxene group
-
clinopyroxene (1)
-
-
-
framework silicates
-
feldspar group
-
alkali feldspar
-
adularia (2)
-
K-feldspar (1)
-
-
-
nepheline group
-
nepheline (1)
-
-
scapolite group
-
scapolite (1)
-
-
silica minerals
-
opal
-
opal-A (1)
-
-
quartz (3)
-
-
-
orthosilicates
-
nesosilicates
-
garnet group (4)
-
zircon group
-
thorite (1)
-
zircon (4)
-
-
-
sorosilicates
-
epidote group
-
epidote (1)
-
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vesuvianite (1)
-
-
-
ring silicates
-
tourmaline group (3)
-
-
sheet silicates
-
chlorite group
-
chlorite (1)
-
-
mica group
-
biotite (1)
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phlogopite (1)
-
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sericite (1)
-
-
-
sulfides
-
arsenopyrite (1)
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covellite (1)
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galena (1)
-
marcasite (1)
-
molybdenite (3)
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pyrite (2)
-
sphalerite (1)
-
-
tellurides
-
tellurobismuthite (1)
-
-
tungstates
-
scheelite (1)
-
wolframite (1)
-
-
-
Primary terms
-
absolute age (9)
-
Africa
-
East Africa
-
Malawi (1)
-
-
Southern Africa
-
Karoo Basin (2)
-
South Africa
-
Bushveld Complex (1)
-
KwaZulu-Natal South Africa (1)
-
Transvaal region (1)
-
-
-
-
Arctic region
-
Svalbard
-
Spitsbergen (1)
-
-
-
Asia
-
Arabian Peninsula
-
Saudi Arabia (1)
-
-
Far East
-
China
-
Heilongjiang China (1)
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Henan China (1)
-
North China Platform (1)
-
Qinling Mountains (1)
-
-
Japan
-
Kyushu
-
Kagoshima Japan (1)
-
-
-
Korea
-
South Korea (1)
-
-
-
Indian Peninsula
-
India
-
Maharashtra India
-
Mumbai India (1)
-
-
-
-
-
Australasia
-
Australia
-
Lachlan fold belt (1)
-
New South Wales Australia (3)
-
Northern Territory Australia (1)
-
Queensland Australia
-
Cloncurry mining district (1)
-
Mount Isa Inlier (1)
-
-
-
-
bibliography (1)
-
brines (3)
-
Canada
-
Eastern Canada
-
Maritime Provinces
-
New Brunswick (1)
-
-
Ontario
-
Algoma District Ontario
-
Mamainse Point (1)
-
-
Batchawana Bay (2)
-
-
Quebec
-
Noranda Quebec (1)
-
-
-
Western Canada
-
Alberta
-
Athabasca Oil Sands (1)
-
-
British Columbia (1)
-
Canadian Cordillera (1)
-
Manitoba (1)
-
Northwest Territories (1)
-
-
-
carbon
-
C-13/C-12 (4)
-
-
Cenozoic
-
Quaternary
-
Pleistocene (1)
-
-
Tertiary
-
Neogene
-
Miocene
-
upper Miocene (1)
-
-
-
Paleogene
-
Eocene
-
lower Eocene (1)
-
-
Oligocene (1)
-
Paleocene (2)
-
-
-
-
clay mineralogy (1)
-
climate change (2)
-
crust (1)
-
crystal chemistry (2)
-
crystal growth (1)
-
crystal structure (1)
-
crystallography (1)
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data processing (2)
-
deformation (2)
-
diagenesis (1)
-
economic geology (33)
-
Europe
-
Central Europe
-
Hungary
-
Borzsony Mountains (1)
-
-
-
Fennoscandia (1)
-
Southern Europe
-
Iberian Peninsula
-
Ossa-Morena Zone (1)
-
Spain
-
Andalusia Spain
-
Seville Spain (1)
-
-
-
-
-
Variscides (1)
-
Western Europe
-
France
-
Central Massif (2)
-
Haute-Vienne France (1)
-
Limousin (1)
-
-
Ireland
-
Galway Ireland
-
Galway Granite (1)
-
-
-
Scandinavia
-
Finland
-
Pirkanmaa Finland
-
Ylojarvi Finland (1)
-
-
-
-
United Kingdom
-
Great Britain
-
Scotland
-
Galloway Scotland (1)
-
-
-
-
-
-
faults (9)
-
folds (1)
-
fractures (4)
-
geochemistry (17)
-
geochronology (3)
-
geophysical methods (7)
-
ground water (2)
-
heat flow (1)
-
hydrogen
-
D/H (3)
-
deuterium (2)
-
-
igneous rocks
-
carbonatites (2)
-
plutonic rocks
-
diabase (1)
-
diorites
-
tonalite (1)
-
trondhjemite (1)
-
-
gabbros (1)
-
granites (8)
-
granodiorites (2)
-
quartz monzonite (2)
-
syenites
-
nepheline syenite (1)
-
-
-
porphyry (1)
-
volcanic rocks
-
andesites (1)
-
basalts (1)
-
dacites (2)
-
pyroclastics
-
ash-flow tuff (1)
-
-
rhyolites (1)
-
-
-
inclusions
-
fluid inclusions (24)
-
-
intrusions (78)
-
isotopes
-
stable isotopes
-
C-13/C-12 (4)
-
D/H (3)
-
deuterium (2)
-
He-4/He-3 (1)
-
Nd-144/Nd-143 (1)
-
Ne-22/Ne-20 (1)
-
O-18 (1)
-
O-18/O-16 (8)
-
S-34/S-32 (8)
-
Sr-87/Sr-86 (1)
-
-
-
magmas (4)
-
maps (1)
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
McMurray Formation (1)
-
-
Upper Cretaceous (4)
-
-
Jurassic
-
Lower Jurassic (1)
-
-
Navajo Sandstone (1)
-
Triassic
-
Upper Triassic
-
Chinle Formation (1)
-
Stormberg Series (1)
-
-
-
-
metal ores
-
arsenic ores (1)
-
base metals (2)
-
bismuth ores (1)
-
cobalt ores (2)
-
copper ores (27)
-
gold ores (19)
-
iron ores (4)
-
lead ores (3)
-
lead-zinc deposits (3)
-
molybdenum ores (15)
-
nickel ores (3)
-
platinum ores (2)
-
polymetallic ores (9)
-
rare earth deposits (3)
-
silver ores (12)
-
tin ores (3)
-
tungsten ores (7)
-
uranium ores (6)
-
zinc ores (3)
-
-
metals
-
actinides
-
uranium (2)
-
-
alkali metals
-
potassium (1)
-
sodium (1)
-
-
alkaline earth metals
-
strontium
-
Sr-87/Sr-86 (1)
-
-
-
cadmium (1)
-
copper (3)
-
gold (1)
-
iron (1)
-
lead (2)
-
mercury (2)
-
niobium (2)
-
platinum group
-
platinum ores (2)
-
-
precious metals (1)
-
rare earths
-
neodymium
-
Nd-144/Nd-143 (1)
-
-
yttrium (2)
-
-
tantalum (1)
-
tin (1)
-
titanium (2)
-
tungsten (2)
-
vanadium (1)
-
zirconium (1)
-
-
metamorphic rocks
-
granulites (1)
-
hornfels (1)
-
metasomatic rocks
-
fenite (1)
-
greisen (1)
-
skarn (5)
-
-
-
metamorphism (4)
-
metasomatism (34)
-
Mexico
-
Chiapas Mexico (1)
-
Chihuahua Mexico
-
Sierra Pena Blanca (1)
-
-
Sonora Mexico
-
Cananea Mexico (1)
-
La Caridad Mine (1)
-
-
-
mineral deposits, genesis (46)
-
mineral exploration (11)
-
mineralogy (1)
-
minerals (1)
-
mining geology (1)
-
noble gases
-
helium
-
He-4/He-3 (1)
-
-
neon
-
Ne-22/Ne-20 (1)
-
-
-
North America
-
Canadian Shield
-
Superior Province
-
Abitibi Belt (1)
-
-
-
Great Lakes region (1)
-
Lake Superior region (1)
-
North American Cordillera
-
Canadian Cordillera (1)
-
-
-
orogeny (2)
-
oxygen
-
O-18 (1)
-
O-18/O-16 (8)
-
-
paleogeography (1)
-
paleomagnetism (1)
-
Paleozoic
-
Cambrian
-
Upper Cambrian
-
Lamotte Sandstone (1)
-
-
-
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breccia pipes
Halogen fractionation during vapor-brine phase separation revealed by in situ Cl, Br, and I analysis of scapolite from the Yixingzhai gold deposit, North China Craton
High-Precision Geochronology of LIP Intrusions: Records of Magma–Sediment Interaction
DIFFERENTIATING TOURMALINE SPECIES VIA CHEMISTRY AND REFLECTANCE SPECTROSCOPY AT THE GIANT COPPER PORPHYRY DEPOSIT AND ASSOCIATED TOURMALINE BRECCIA PIPES: TESTING TOURMALINE AS A MINERAL VECTOR
3D ground-penetrating radar attribute classification: A case study from a paleokarst breccia pipe in the Billefjorden area on Spitsbergen, Svalbard
Formation of Sediment-Hosted Opal-A G at Lightning Ridge (New South Wales, Australia): Refining the Deep Weathering Model
Enrichment of heavy REE and Th in carbonatite-derived fenite breccia
Multistage development of a hydrothermal W deposit during the Variscan late-orogenic evolution: the Puy-les-Vignes breccia pipe (Massif Central, France)
Electromagnetic characterization of epithermal gold deposits: A case study from the Tuoniuhe gold deposit, Northeast China
ABSTRACT Fluid release structures resulting from the interaction of igneous intrusions with sedimentary basins form an important part of the evolution of large igneous provinces. Hydrothermal breccia pipes formed in the Karoo Basin in South Africa during emplacement of igneous sills in the Karoo large igneous province represent one of the best-exposed expressions of such venting structures. Earlier work has shown that degassing of thermogenic CO 2 and CH 4 through the breccia pipes may have contributed to the Early Jurassic environmental changes. Here, we present the first detailed analysis of the distribution of breccia pipes in the western parts of the Karoo Basin. We mapped 431 pipes in a 650 km 2 area using outcrop data. The pipes are rooted in contact aureoles around four sills emplaced in organic-rich Ecca Group shale, and thermal modeling of sill cooling and contact metamorphism gives a maximum temperature of 675 °C near the sill contacts, sufficient to convert a significant fraction of the organic carbon to gas. Model estimates indicate that metamorphism in the 650 km 2 area generated 75–88 Gt of CO 2 , depending on actual sill thicknesses and emplacement levels. When further up-scaled, an area of 7400–8700 km 2 (i.e., less than 2% of the area in the Karoo Basin intruded by sills) would be required to generate 1000 Gt of CO 2 . In order to characterize the degassing pipes, their geographical positions and diameters were analyzed using several point-pattern methods. The results showed that the pipes (1) have diameters in the 11–177 m range (average 44 m), (2) are spaced with an average nearest-neighbor distance of 452 m, and (3) are overall randomly spaced but with weak overdispersion at very small scales (<50 m) and weak clusters at larger scales (400–3000 m). In contrast to studies of volcanic pipe spacing, this study on breccia pipes does not indicate that the pipe spacing is controlled by any large-scale geophysical parameters such as crustal or basin thicknesses. Conclusions point to the pipes being formed following sill emplacement and pressure increase in the low-permeability organic-rich shale, followed by rapid carbon degassing, emphasizing their important role in the Early Jurassic climate change and oceanic anoxic event.
Abstract: The Panna–Mukta fields host hydrocarbons in the Bassein Formation Eocene–Oligocene ramp limestones. The pore system is almost wholly secondary, comprising microporosity, mouldic porosity, vugs, solution-enlarged stylolites and fractures. Although petrographical evidence points to dissolution after extensive late cementation, the presence of a high permeability layer close to a palaeokarstic surface at the Eocene–Oligocene boundary has raised the possibility that this secondary porosity could be related to subaerial exposure. However, the Panna–Mukta reservoirs show a strong correlation between secondary matrix porosity and stylolite density measured from cores. Stylolites only developed in ‘clean’ limestones lacking argillaceous material, whereas more argillaceous limestones in the succession are characterized by dissolution seams and have poor reservoir quality. These cleaner limestones occur preferentially below the Eocene–Oligocene boundary, representing an upwards-shallowing sequence, whereas the argillaceous limestones occur further below the Eocene–Oligocene boundary in the lower part of the same shallowing-upwards sequence and in the transgressive limestones at the base of the Bassein A. This secondary porosity distribution suggests movement of corrosive fluids along pre-existing stylolites. Despite an apparent link between porosity distribution and an unconformity, secondary porosity development was mesogenetic and related to the distribution of facies that favoured stylolites that acted as conduits for the flow of corrosive fluids. The Bassein Formation reservoirs show unequivocal evidence of significant porosity development by mesogenetic dissolution but the exact process or processes by which such porosity creation occurs requires further work.
Geology and Genesis of the Cerro la Mina Porphyry-High Sulfidation Au (Cu-Mo) Prospect, Mexico
Breccia pipe and sinkhole linked fluidized beds and debris flows in the Athabasca Oil Sands: dynamics of evaporite karst collapse-induced fault block collisions
Breccia formation during intrusion of a dolerite sill: an example from Sheffield Beach, KwaZulu-Natal North Coast, South Africa
U-Pb, Re-Os, and Ar/Ar Geochronology of Rare Earth Element (REE)-Rich Breccia Pipes and Associated Host Rocks from the Mesoproterozoic Pea Ridge Fe-REE-Au Deposit, St. Francois Mountains, Missouri
Mineralogy, Chemistry, and Fluid-Aided Evolution of the Pea Ridge Fe Oxide-(Y + REE) Deposit, Southeast Missouri, USA
Mineral Thermometry and Fluid Inclusion Studies of the Pea Ridge Iron Oxide-Apatite–Rare Earth Element Deposit, Mesoproterozoic St. Francois Mountains Terrane, Southeast Missouri, USA
Nb-ti-y-hree-w-u Oxide Minerals with Uncommon Compositions Associated with the Tungsten Mineralization in the Puy-les-vignes Deposit (massif Central, France): Evidence For Rare-metal Mobilization By Late Hydrothermal Fluids with a Peralkaline Signature
Regional setting and deposit geology of the Golden Sunlight Mine: An example of responsible resource extraction
Abstract The Barrick Golden Sunlight Mine (GSM) in Whitehall, Montana, is an industry leader in safe, responsible resource extraction. With more than 3 million ounces of gold poured since 1983, and current proven and probable reserves of 318,000 ounces of gold, GSM is the largest gold producer in Montana. The gold-silver deposit is localized in a hydrothermal breccia pipe related to Late Cretaceous latite porphyry magmatism hosted by the Mesoproterozoic Belt Supergroup, and is influenced by younger cross-cutting faults and fracture systems. The deposit has been mined by both underground and open pit methods, and the current open pit operation was recently permitted for expansion. The mill and tailings operations practice efficient and environmentally responsible resource recovery by processing ore from historical tailings and dumps from around the state in addition to ore from the Golden Sunlight property. This trip will explore the complex geologic and tectonic controls on mineralization and review how GSM has addressed the technical challenges of mining, milling, and reclamation.