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NARROW
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Africa
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Afar (1)
-
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Bear River basin (1)
-
Bear River Range (1)
-
Beaver Creek (1)
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Canada
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Western Canada
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British Columbia (1)
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Eagle Lake (1)
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Europe
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Western Europe
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Iceland (2)
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Madison Range (14)
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North America
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Basin and Range Province (2)
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Canadian Shield
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Grenville Province (1)
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Great Plains (1)
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Purcell Mountains (1)
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Rocky Mountains
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Northern Rocky Mountains (3)
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U. S. Rocky Mountains
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Absaroka Range
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Beartooth Mountains (1)
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-
Bridger Range (8)
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Gravelly Range (1)
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Spanish Peaks (1)
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Tobacco Root Mountains (3)
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-
-
Rocky Mountains foreland (2)
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Western Interior
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Western Interior Seaway (1)
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Western Overthrust Belt (2)
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Old Faithful Geyser (1)
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Pioneer Mountains (1)
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Ruby Range (3)
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United States
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California
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Alameda County California
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Livermore California (1)
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San Diego County California (1)
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Southern California (2)
-
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Colorado (1)
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Gallatin Range (2)
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Idaho
-
Snake River plain (3)
-
-
Montana
-
Beaverhead County Montana (3)
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Bridger Range (8)
-
Broadwater County Montana (4)
-
Deer Lodge County Montana (1)
-
Gallatin County Montana
-
Hebgen Lake (14)
-
Three Forks Montana (3)
-
-
Granite County Montana (1)
-
Gravelly Range (1)
-
Jefferson County Montana (1)
-
Lewis and Clark County Montana (1)
-
Madison County Montana
-
Tobacco Root Mountains (3)
-
-
Meagher County Montana (1)
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Park County Montana (5)
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Powell County Montana (1)
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Ravalli County Montana (1)
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Silver Bow County Montana (1)
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Nebraska (1)
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New York
-
Adirondack Mountains (1)
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Essex County New York (1)
-
Saint Lawrence County New York (1)
-
Warren County New York (1)
-
-
U. S. Rocky Mountains
-
Absaroka Range
-
Beartooth Mountains (1)
-
-
Bridger Range (8)
-
Gravelly Range (1)
-
Spanish Peaks (1)
-
Tobacco Root Mountains (3)
-
-
Utah
-
Cache County Utah (1)
-
Wasatch Plateau (1)
-
Washington County Utah (1)
-
-
Washington (2)
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Western U.S. (2)
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Wyoming
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Teton County Wyoming (2)
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Wyoming Province (4)
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Yellowstone National Park (4)
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commodities
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coal deposits (1)
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energy sources (1)
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geothermal energy (1)
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metal ores
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base metals (1)
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polymetallic ores (1)
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mineral deposits, genesis (2)
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oil and gas fields (1)
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petroleum
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natural gas (1)
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talc deposits (1)
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-
elements, isotopes
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carbon
-
C-13/C-12 (3)
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organic carbon (1)
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hydrogen (1)
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isotope ratios (7)
-
isotopes
-
radioactive isotopes
-
Be-10 (1)
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Pb-206/Pb-204 (1)
-
-
stable isotopes
-
C-13/C-12 (3)
-
He-3 (1)
-
Nd-144/Nd-143 (2)
-
O-18/O-16 (3)
-
Pb-206/Pb-204 (1)
-
S-34/S-32 (1)
-
Sr-87/Sr-86 (1)
-
-
-
metals
-
alkaline earth metals
-
beryllium
-
Be-10 (1)
-
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strontium
-
Sr-87/Sr-86 (1)
-
-
-
lead
-
Pb-206/Pb-204 (1)
-
-
rare earths
-
neodymium
-
Nd-144/Nd-143 (2)
-
-
-
-
noble gases
-
helium
-
He-3 (1)
-
-
-
oxygen
-
O-18/O-16 (3)
-
-
sulfur
-
S-34/S-32 (1)
-
-
-
fossils
-
Chordata
-
Vertebrata
-
Tetrapoda
-
Mammalia
-
Theria
-
Eutheria
-
Perissodactyla
-
Hippomorpha
-
Equidae (1)
-
-
-
Rodentia (1)
-
-
-
-
-
-
-
Invertebrata
-
Brachiopoda
-
Articulata
-
Spiriferida
-
Cyrtospirifer (1)
-
-
-
Inarticulata
-
Lingula (1)
-
-
-
Cnidaria
-
Hydrozoa (1)
-
-
-
microfossils (2)
-
palynomorphs
-
acritarchs (1)
-
miospores (1)
-
-
-
geochronology methods
-
Ar/Ar (3)
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hydration of glass (1)
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K/Ar (3)
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Pb/Pb (1)
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Rb/Sr (1)
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Sm/Nd (1)
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U/Pb (8)
-
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geologic age
-
Cenozoic
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Quaternary
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Holocene (3)
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Pleistocene
-
Bishop Tuff (1)
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upper Pleistocene (1)
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-
upper Quaternary
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Bull Lake Glaciation (1)
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Pinedale Glaciation (2)
-
-
-
Tertiary
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Neogene
-
Miocene
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Barstovian (1)
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upper Miocene (1)
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-
Pliocene (1)
-
-
Paleogene
-
Eocene
-
Absaroka Supergroup (1)
-
lower Eocene
-
Ypresian (1)
-
-
-
Oligocene (1)
-
Renova Formation (1)
-
-
-
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Albian (2)
-
Blackleaf Formation (1)
-
Mowry Shale (1)
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Muddy Sandstone (1)
-
-
Middle Cretaceous (1)
-
Upper Cretaceous
-
Frontier Formation (1)
-
Maestrichtian (1)
-
Senonian (1)
-
-
-
Triassic
-
Lower Triassic
-
Dinwoody Formation (1)
-
-
-
-
Paleozoic
-
Cambrian
-
Middle Cambrian
-
Flathead Sandstone (2)
-
-
Upper Cambrian
-
Pilgrim Formation (2)
-
-
-
Carboniferous
-
Mississippian
-
Lower Mississippian
-
Lodgepole Formation (2)
-
Osagian (1)
-
Tournaisian (1)
-
-
Madison Group (1)
-
Mission Canyon Limestone (2)
-
Upper Mississippian
-
Meramecian (1)
-
-
-
-
Devonian
-
Upper Devonian
-
Famennian
-
upper Famennian (1)
-
-
Jefferson Group (1)
-
-
-
Permian
-
Park City Formation (1)
-
Phosphoria Formation (1)
-
Upper Permian (1)
-
-
Sauk Sequence (1)
-
-
Precambrian
-
Archean
-
Neoarchean (1)
-
-
Stillwater Complex (1)
-
upper Precambrian
-
Proterozoic
-
Mesoproterozoic
-
Belt Supergroup (2)
-
Newland Limestone (1)
-
-
Neoproterozoic
-
Tonian (1)
-
-
Paleoproterozoic (2)
-
-
-
-
-
igneous rocks
-
igneous rocks
-
plutonic rocks
-
diabase (1)
-
-
volcanic rocks
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adakites (1)
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andesites (1)
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dacites (1)
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glasses
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obsidian (1)
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-
pyroclastics
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ignimbrite (1)
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rhyolite tuff (1)
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tuff (1)
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welded tuff (2)
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-
rhyolites (1)
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-
-
-
metamorphic rocks
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metamorphic rocks
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cataclasites (1)
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gneisses (5)
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metaigneous rocks
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metagranite (1)
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-
metasedimentary rocks (3)
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metavolcanic rocks (1)
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mylonites (2)
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schists (1)
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-
minerals
-
carbonates
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calcite (1)
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dolomite (1)
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minerals (1)
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native elements
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graphite (1)
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oxides
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iron oxides (1)
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magnetite (1)
-
-
phosphates
-
monazite (1)
-
-
silicates
-
chain silicates
-
amphibole group
-
clinoamphibole
-
hornblende (3)
-
-
-
pyroxene group (1)
-
-
framework silicates
-
feldspar group
-
alkali feldspar
-
sanidine (1)
-
-
-
silica minerals
-
quartz (1)
-
-
-
orthosilicates
-
nesosilicates
-
garnet group (1)
-
zircon group
-
zircon (9)
-
-
-
-
sheet silicates
-
mica group
-
muscovite (1)
-
-
-
-
sulfates (1)
-
sulfides
-
pyrite (1)
-
-
-
Primary terms
-
absolute age (13)
-
Africa
-
Afar (1)
-
-
biogeography (1)
-
Canada
-
Western Canada
-
British Columbia (1)
-
-
-
carbon
-
C-13/C-12 (3)
-
organic carbon (1)
-
-
Cenozoic
-
Quaternary
-
Holocene (3)
-
Pleistocene
-
Bishop Tuff (1)
-
upper Pleistocene (1)
-
-
upper Quaternary
-
Bull Lake Glaciation (1)
-
Pinedale Glaciation (2)
-
-
-
Tertiary
-
Neogene
-
Miocene
-
Barstovian (1)
-
upper Miocene (1)
-
-
Pliocene (1)
-
-
Paleogene
-
Eocene
-
Absaroka Supergroup (1)
-
lower Eocene
-
Ypresian (1)
-
-
-
Oligocene (1)
-
Renova Formation (1)
-
-
-
-
Chordata
-
Vertebrata
-
Tetrapoda
-
Mammalia
-
Theria
-
Eutheria
-
Perissodactyla
-
Hippomorpha
-
Equidae (1)
-
-
-
Rodentia (1)
-
-
-
-
-
-
-
coal deposits (1)
-
crust (1)
-
crystal growth (1)
-
crystal structure (1)
-
deformation (7)
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diagenesis (1)
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earthquakes (12)
-
economic geology (2)
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energy sources (1)
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engineering geology (1)
-
Europe
-
Western Europe
-
Iceland (2)
-
-
-
faults (20)
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folds (8)
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foliation (4)
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fractures (1)
-
geochemistry (5)
-
geochronology (4)
-
geomorphology (5)
-
geophysical methods (3)
-
geothermal energy (1)
-
glacial geology (2)
-
ground water (1)
-
hydrogen (1)
-
hydrogeology (1)
-
igneous rocks
-
plutonic rocks
-
diabase (1)
-
-
volcanic rocks
-
adakites (1)
-
andesites (1)
-
dacites (1)
-
glasses
-
obsidian (1)
-
-
pyroclastics
-
ignimbrite (1)
-
rhyolite tuff (1)
-
tuff (1)
-
welded tuff (2)
-
-
rhyolites (1)
-
-
-
inclusions (1)
-
intrusions (4)
-
Invertebrata
-
Brachiopoda
-
Articulata
-
Spiriferida
-
Cyrtospirifer (1)
-
-
-
Inarticulata
-
Lingula (1)
-
-
-
Cnidaria
-
Hydrozoa (1)
-
-
-
isotopes
-
radioactive isotopes
-
Be-10 (1)
-
Pb-206/Pb-204 (1)
-
-
stable isotopes
-
C-13/C-12 (3)
-
He-3 (1)
-
Nd-144/Nd-143 (2)
-
O-18/O-16 (3)
-
Pb-206/Pb-204 (1)
-
S-34/S-32 (1)
-
Sr-87/Sr-86 (1)
-
-
-
land use (1)
-
lava (1)
-
lineation (2)
-
magmas (3)
-
mantle (3)
-
maps (1)
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Albian (2)
-
Blackleaf Formation (1)
-
Mowry Shale (1)
-
Muddy Sandstone (1)
-
-
Middle Cretaceous (1)
-
Upper Cretaceous
-
Frontier Formation (1)
-
Maestrichtian (1)
-
Senonian (1)
-
-
-
Triassic
-
Lower Triassic
-
Dinwoody Formation (1)
-
-
-
-
metal ores
-
base metals (1)
-
polymetallic ores (1)
-
-
metals
-
alkaline earth metals
-
beryllium
-
Be-10 (1)
-
-
strontium
-
Sr-87/Sr-86 (1)
-
-
-
lead
-
Pb-206/Pb-204 (1)
-
-
rare earths
-
neodymium
-
Nd-144/Nd-143 (2)
-
-
-
-
metamorphic rocks
-
cataclasites (1)
-
gneisses (5)
-
metaigneous rocks
-
metagranite (1)
-
-
metasedimentary rocks (3)
-
metavolcanic rocks (1)
-
mylonites (2)
-
schists (1)
-
-
metamorphism (5)
-
metasomatism (2)
-
mineral deposits, genesis (2)
-
minerals (1)
-
noble gases
-
helium
-
He-3 (1)
-
-
-
North America
-
Basin and Range Province (2)
-
Canadian Shield
-
Grenville Province (1)
-
-
Great Plains (1)
-
Purcell Mountains (1)
-
Rocky Mountains
-
Northern Rocky Mountains (3)
-
U. S. Rocky Mountains
-
Absaroka Range
-
Beartooth Mountains (1)
-
-
Bridger Range (8)
-
Gravelly Range (1)
-
Spanish Peaks (1)
-
Tobacco Root Mountains (3)
-
-
-
Rocky Mountains foreland (2)
-
Western Interior
-
Western Interior Seaway (1)
-
-
Western Overthrust Belt (2)
-
-
oil and gas fields (1)
-
orogeny (4)
-
oxygen
-
O-18/O-16 (3)
-
-
paleoclimatology (2)
-
paleoecology (1)
-
paleogeography (2)
-
paleontology (1)
-
Paleozoic
-
Cambrian
-
Middle Cambrian
-
Flathead Sandstone (2)
-
-
Upper Cambrian
-
Pilgrim Formation (2)
-
-
-
Carboniferous
-
Mississippian
-
Lower Mississippian
-
Lodgepole Formation (2)
-
Osagian (1)
-
Tournaisian (1)
-
-
Madison Group (1)
-
Mission Canyon Limestone (2)
-
Upper Mississippian
-
Meramecian (1)
-
-
-
-
Devonian
-
Upper Devonian
-
Famennian
-
upper Famennian (1)
-
-
Jefferson Group (1)
-
-
-
Permian
-
Park City Formation (1)
-
Phosphoria Formation (1)
-
Upper Permian (1)
-
-
Sauk Sequence (1)
-
-
palynomorphs
-
acritarchs (1)
-
miospores (1)
-
-
paragenesis (2)
-
petroleum
-
natural gas (1)
-
-
petrology (2)
-
phase equilibria (1)
-
plate tectonics (2)
-
Precambrian
-
Archean
-
Neoarchean (1)
-
-
Stillwater Complex (1)
-
upper Precambrian
-
Proterozoic
-
Mesoproterozoic
-
Belt Supergroup (2)
-
Newland Limestone (1)
-
-
Neoproterozoic
-
Tonian (1)
-
-
Paleoproterozoic (2)
-
-
-
-
sea-level changes (2)
-
sedimentary petrology (1)
-
sedimentary rocks
-
carbonate rocks
-
dolostone (1)
-
limestone (3)
-
-
chemically precipitated rocks
-
iron formations (1)
-
-
clastic rocks
-
arkose (2)
-
conglomerate (1)
-
mudstone (1)
-
sandstone (6)
-
shale (4)
-
siltstone (1)
-
-
coal (2)
-
-
sedimentary structures
-
bedding plane irregularities
-
ripple marks (1)
-
-
biogenic structures
-
microbial mats (1)
-
-
-
sedimentation (7)
-
sediments
-
clastic sediments
-
boulders (1)
-
gravel (1)
-
outwash (1)
-
sand (2)
-
-
-
seismology (2)
-
soils (2)
-
springs (2)
-
stratigraphy (5)
-
structural analysis (2)
-
structural geology (7)
-
sulfur
-
S-34/S-32 (1)
-
-
talc deposits (1)
-
tectonics
-
neotectonics (6)
-
-
thermal waters (2)
-
underground installations (1)
-
United States
-
California
-
Alameda County California
-
Livermore California (1)
-
-
San Diego County California (1)
-
Southern California (2)
-
-
Colorado (1)
-
Gallatin Range (2)
-
Idaho
-
Snake River plain (3)
-
-
Montana
-
Beaverhead County Montana (3)
-
Bridger Range (8)
-
Broadwater County Montana (4)
-
Deer Lodge County Montana (1)
-
Gallatin County Montana
-
Hebgen Lake (14)
-
Three Forks Montana (3)
-
-
Granite County Montana (1)
-
Gravelly Range (1)
-
Jefferson County Montana (1)
-
Lewis and Clark County Montana (1)
-
Madison County Montana
-
Tobacco Root Mountains (3)
-
-
Meagher County Montana (1)
-
Park County Montana (5)
-
Powell County Montana (1)
-
Ravalli County Montana (1)
-
Silver Bow County Montana (1)
-
-
Nebraska (1)
-
New York
-
Adirondack Mountains (1)
-
Essex County New York (1)
-
Saint Lawrence County New York (1)
-
Warren County New York (1)
-
-
U. S. Rocky Mountains
-
Absaroka Range
-
Beartooth Mountains (1)
-
-
Bridger Range (8)
-
Gravelly Range (1)
-
Spanish Peaks (1)
-
Tobacco Root Mountains (3)
-
-
Utah
-
Cache County Utah (1)
-
Wasatch Plateau (1)
-
Washington County Utah (1)
-
-
Washington (2)
-
Western U.S. (2)
-
Wyoming
-
Teton County Wyoming (2)
-
-
Wyoming Province (4)
-
Yellowstone National Park (4)
-
-
volcanology (1)
-
weathering (1)
-
-
sedimentary rocks
-
sedimentary rocks
-
carbonate rocks
-
dolostone (1)
-
limestone (3)
-
-
chemically precipitated rocks
-
iron formations (1)
-
-
clastic rocks
-
arkose (2)
-
conglomerate (1)
-
mudstone (1)
-
sandstone (6)
-
shale (4)
-
siltstone (1)
-
-
coal (2)
-
-
-
sedimentary structures
-
channels (1)
-
sedimentary structures
-
bedding plane irregularities
-
ripple marks (1)
-
-
biogenic structures
-
microbial mats (1)
-
-
-
-
sediments
-
sediments
-
clastic sediments
-
boulders (1)
-
gravel (1)
-
outwash (1)
-
sand (2)
-
-
-
-
soils
-
paleosols (2)
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soils (2)
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Strong seismic anisotropy due to upwelling flow at the root of the Yellowstone mantle plume
Eocene Andesitic Adakite from Lone Mountain, Southwestern Montana
Mesoproterozoic–Early Cretaceous provenance and paleogeographic evolution of the Northern Rocky Mountains: Insights from the detrital zircon record of the Bridger Range, Montana, USA
Geochemical, isotopic, and U–Pb zircon study of the central and southern portions of the 780 Ma Gunbarrel Large Igneous Province in western Laurentia
Sulfate-containing calcite: crystallographic characterization of natural and synthetic materials
Late Miocene rise and fall of C 4 grasses in the western United States linked to aridification and uplift
Facies and stratigraphic architecture of the Upper Devonian–Lower Mississippian Sappington Formation, southwestern Montana: A potential outcrop analog for the Bakken Formation
Palynologic delineation of the Devonian–Carboniferous boundary, West-Central Montana, USA
Pyrite-walled tube structures in a Mesoproterozoic sediment-hosted metal sulfide deposit
Oxygen isotope thermometry reveals high magmatic temperatures and short residence times in Yellowstone and other hot-dry rhyolites compared to cold-wet systems
Foreland-directed propagation of high-grade tectonism in the deep roots of a Paleoproterozoic collisional orogen, SW Montana, USA
Bulk electric conductivity response to soil and rock CO 2 concentration during controlled CO 2 release experiments: Observations and analytic modeling
Linking rapid magma reservoir assembly and eruption trigger mechanisms at evolved Yellowstone-type supervolcanoes
Strain localization in the Spanish Creek mylonite, Northern Madison Range, southwest Montana, U.S.A.
Abstract The catastrophic Hebgen Lake earthquake of 18 August 1959 (M W 7.3) led many geoscientists to develop new methods to better understand active tectonics in extensional tectonic regimes that address seismic hazards. The Madison Range fault system and adjacent Hebgen Lake–Red Canyon fault system provide an intermountain-active tectonic analog for regional analyses of extensional crustal deformation. The Madison Range fault system comprises fault zones (~100 km in length) that have multiple salients and embayments marked by preexisting structures exposed in the footwall. Quaternary tectonic activity rates differ along the length of the fault system, with less displacement to the north. Within the Hebgen Lake basin, the 1959 earthquake is the latest slip event in the Hebgen Lake–Red Canyon fault system and southern Madison Range fault system. Geomorphic and paleoseismic investigations indicate previous faulting events on both fault systems. Surficial geologic mapping and historic seismicity support a coseismic structural linkage between the Madison Range and Hebgen Lake–Red Canyon fault systems. On this trip, we will look at Quaternary surface ruptures that characterize prehistoric earthquake magnitudes. The one-day field trip begins and ends in Bozeman, and includes an overview of the active tectonics within the Madison Valley and Hebgen Lake basin, southwestern Montana. We will also review geologic evidence, which includes new geologic maps and geomorphic analyses that demonstrate preexisting structural controls on surface rupture patterns along the Madison Range and Hebgen Lake–Red Canyon fault systems.
Abstract On this field trip, participants will get their hands dirty while characterizing soils formed on five different rock types: Archean Gneiss, Flathead Sandstone, Wolsey Shale, Meagher Limestone, and Absaroka Volcanics (a basaltic andesite rock). We first recap prior soil survey efforts across the Gallatin National Forest in southwestern Montana and introduce a state factor approach to understanding soils. For over 50 years, Montana State University faculty have explored parts of this lithosequence, using it as a natural laboratory for thousands of students. We continue this tradition with this field guide, emphasizing how the combination of field and laboratory data can enrich our understanding of soil processes. We will observe and measure striking differences in soils; these differences in physical and chemical properties, from textures and colors to pH and elemental composition, are discussed in the context of quantifying the influence of the underlying rock on soil properties. We use these differences to ask whether heterogeneity in soil properties justifies the inference that soil properties are dominated by the underlying lithology. We conclude that the underlying rock strongly influences soil properties, but in variable ways across this lithosequence. This influence is both direct and indirect: chemical weathering of the rock leads to compositional changes in overlying soil, but rock weathering also leads to coarse fragments in the soil profile, which alters soil hydrology.
The Yellowstone and Regal talc mines and their geologic setting in southwestern Montana
Abstract We summarize the geologic settings, generalized geology, and inferred conditions of talc formation for two major deposits in southwestern Montana. Imerys Talc operates the Yellowstone Mine in the Gravelly Range. Barretts Minerals Inc., a subsidiary of Minerals Technologies Incorporated, mines talc from two large deposits—the Regal and the Treasure—in the southern Ruby Range. Talc mineralization in southwestern Montana is associated with hydrothermal alteration of Archean dolomitic marbles along faults in the southern margin of the middle Proterozoic Belt Seaway. Conditions of talc formation appear to have varied across the region and probably range from shallow hot spring systems to connate brine circulation pathways in Belt basin sediments. A road log description of the geology along a loop from Bozeman to Dillon, Montana, to visit both the Yellowstone and Regal talc mines accompanies this paper.