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NARROW
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Africa
-
Afar (1)
-
West Africa
-
Sierra Leone (1)
-
-
-
Arctic Ocean
-
Norwegian Sea
-
Jan Mayen Ridge (1)
-
-
-
Asia
-
Far East
-
Japan (1)
-
-
Kamchatka Russian Federation
-
Kamchatka Peninsula
-
Uzon (1)
-
-
-
-
Atlantic Ocean
-
North Atlantic
-
Great Meteor Seamount (1)
-
-
-
Australasia
-
New Zealand
-
Auckland volcanic field (1)
-
Okataina volcanic centre (1)
-
Tarawera volcanic complex (1)
-
Taupo (2)
-
Taupo volcanic zone (3)
-
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-
Canada
-
Western Canada
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Yukon Territory (1)
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Cascade Range (3)
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Cascadia subduction zone (1)
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Channeled Scabland (1)
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Coast Ranges (2)
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Commonwealth of Independent States
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Russian Federation
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Kamchatka Russian Federation
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Kamchatka Peninsula
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Uzon (1)
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-
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East Pacific Ocean Islands
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Hawaii
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Hawaii County Hawaii
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Hawaii Island
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Hualalai (1)
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Kilauea (2)
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Kohala (1)
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Mauna Kea (1)
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Mauna Loa (1)
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Europe
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Alps
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Central Alps
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Rhaetian Alps
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Adamello Massif (1)
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-
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Swiss Alps (1)
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-
Central Europe
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Switzerland
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Swiss Alps (1)
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-
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Southern Europe
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Italy
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Lombardy Italy
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Adamello Massif (1)
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Sicily Italy
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Lipari Islands
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Western Europe
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Iceland (3)
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Yakutat Terrane (1)
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North Island (4)
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Oceania
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Polynesia
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Hawaii
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Hawaii County Hawaii
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Hawaii Island
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Hualalai (1)
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Kilauea (2)
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Kohala (1)
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Mauna Kea (1)
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Mauna Loa (1)
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Samoa (1)
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Pacific Coast (2)
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Pacific Ocean
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United States
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Alaska
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Arizona
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Meteor Crater (1)
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California
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Northern California (3)
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Colorado (1)
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Columbia Plateau (1)
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Great Basin (5)
-
Hawaii
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Hawaii County Hawaii
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Hawaii Island
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Hualalai (1)
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Kilauea (2)
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Kohala (1)
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Mauna Kea (1)
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-
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Mauna Loa (1)
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Idaho
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Idaho County Idaho (1)
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Idaho National Laboratory (1)
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Snake River plain (24)
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Twin Falls County Idaho (1)
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Idaho Batholith (2)
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Montana
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Nevada
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East Humboldt Range (1)
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Esmeralda County Nevada
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Oregon
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U. S. Rocky Mountains
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Utah
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Virginia (1)
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Washington
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Western U.S. (15)
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Wyoming
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Fremont County Wyoming (2)
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commodities
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elements, isotopes
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isotope ratios (14)
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isotopes
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Be-10/Be-9 (1)
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Pb-206/Pb-204 (3)
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Pb-207/Pb-204 (2)
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Pb-208/Pb-204 (2)
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stable isotopes
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Be-10/Be-9 (1)
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C-13/C-12 (1)
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He-4/He-3 (3)
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Li-6 (1)
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Li-7 (1)
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Li-7/Li-6 (1)
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Nd-144/Nd-143 (3)
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O-18/O-16 (4)
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Pb-206/Pb-204 (3)
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Pb-207/Pb-204 (2)
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Pb-208/Pb-204 (2)
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Sr-87/Sr-86 (5)
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metals
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alkali metals
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lithium
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Li-6 (1)
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Li-7 (1)
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Li-7/Li-6 (1)
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rubidium (1)
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alkaline earth metals
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barium (1)
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beryllium
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Be-10/Be-9 (1)
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strontium
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Sr-87/Sr-86 (5)
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-
-
iron (1)
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lead
-
Pb-206/Pb-204 (3)
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Pb-207/Pb-204 (2)
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Pb-208/Pb-204 (2)
-
-
rare earths
-
neodymium
-
Nd-144/Nd-143 (3)
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-
yttrium (1)
-
-
-
noble gases
-
helium
-
He-4/He-3 (3)
-
-
-
oxygen
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O-18/O-16 (4)
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-
sulfur (1)
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geochronology methods
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(U-Th)/He (2)
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Ar/Ar (7)
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fission-track dating (2)
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geologic age
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Cenozoic
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Quaternary
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Tertiary
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Neogene
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upper Miocene (4)
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Pliocene
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upper Pliocene (1)
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Paleogene
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Eocene
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middle Eocene
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Tyee Formation (1)
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Umpqua Formation (1)
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Oligocene
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Fish Canyon Tuff (1)
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Paleocene (1)
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upper Cenozoic (1)
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Mesozoic
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Cretaceous
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Upper Cretaceous (2)
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Paleozoic (1)
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Precambrian
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Archean (1)
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upper Precambrian
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Proterozoic
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Neoproterozoic (1)
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igneous rocks
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igneous rocks
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kimberlite (1)
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anorthosite (1)
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gabbros (1)
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granites
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A-type granites (1)
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charnockite (1)
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monzonites
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mangerite (1)
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-
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volcanic rocks
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basalts
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flood basalts (7)
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mid-ocean ridge basalts (1)
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shoshonite (1)
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basanite
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ankaramite (1)
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glasses
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volcanic glass (1)
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pyroclastics
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ignimbrite (7)
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rhyolite tuff (3)
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tuff (7)
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welded tuff (1)
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-
rhyolites (12)
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trachyandesites
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metamorphic rocks
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minerals
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oxides
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phosphates
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apatite (3)
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silicates
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chain silicates
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pyroxene group (1)
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framework silicates
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feldspar group
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alkali feldspar
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sanidine (3)
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plagioclase (1)
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silica minerals
-
quartz (2)
-
-
-
orthosilicates
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nesosilicates
-
zircon group
-
zircon (9)
-
-
-
sorosilicates
-
epidote group
-
allanite (1)
-
-
-
-
-
-
Primary terms
-
absolute age (16)
-
Africa
-
Afar (1)
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West Africa
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Sierra Leone (1)
-
-
-
Arctic Ocean
-
Norwegian Sea
-
Jan Mayen Ridge (1)
-
-
-
Asia
-
Far East
-
Japan (1)
-
-
Kamchatka Russian Federation
-
Kamchatka Peninsula
-
Uzon (1)
-
-
-
-
Atlantic Ocean
-
North Atlantic
-
Great Meteor Seamount (1)
-
-
-
Australasia
-
New Zealand
-
Auckland volcanic field (1)
-
Okataina volcanic centre (1)
-
Tarawera volcanic complex (1)
-
Taupo (2)
-
Taupo volcanic zone (3)
-
-
-
Canada
-
Western Canada
-
Yukon Territory (1)
-
-
-
carbon
-
C-13/C-12 (1)
-
-
Cenozoic
-
Glenns Ferry Formation (1)
-
Quaternary
-
Pleistocene
-
Bishop Tuff (2)
-
lower Pleistocene (1)
-
-
-
Tertiary
-
Challis Volcanics (1)
-
Neogene
-
Miocene
-
Columbia River Basalt Group (9)
-
Grande Ronde Basalt (1)
-
middle Miocene (4)
-
upper Miocene (4)
-
-
Pliocene
-
upper Pliocene (1)
-
-
-
Paleogene
-
Eocene
-
middle Eocene
-
Tyee Formation (1)
-
-
Umpqua Formation (1)
-
-
Oligocene
-
Fish Canyon Tuff (1)
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Paleocene (1)
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-
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upper Cenozoic (1)
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core (1)
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crust (14)
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crystal chemistry (1)
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deformation (5)
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earthquakes (3)
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East Pacific Ocean Islands
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Hawaii
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Hawaii County Hawaii
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Hualalai (1)
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Kohala (1)
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Mauna Kea (1)
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-
-
Mauna Loa (1)
-
-
-
Europe
-
Alps
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Central Alps
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Rhaetian Alps
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Adamello Massif (1)
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-
-
Swiss Alps (1)
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-
Central Europe
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Switzerland
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Swiss Alps (1)
-
-
-
Southern Europe
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Italy
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Lombardy Italy
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Adamello Massif (1)
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-
Sicily Italy
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Lipari Islands
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Lipari Island (1)
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-
-
-
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Western Europe
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Iceland (3)
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faults (10)
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folds (2)
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fractures (1)
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geomorphology (3)
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geophysical methods (4)
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government agencies (1)
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ground water (1)
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heat flow (3)
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hydrology (1)
-
igneous rocks
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kimberlite (1)
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plutonic rocks
-
anorthosite (1)
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gabbros (1)
-
granites
-
A-type granites (1)
-
charnockite (1)
-
-
monzonites
-
mangerite (1)
-
-
-
volcanic rocks
-
basalts
-
flood basalts (7)
-
mid-ocean ridge basalts (1)
-
shoshonite (1)
-
-
basanite
-
ankaramite (1)
-
-
glasses
-
volcanic glass (1)
-
-
pyroclastics
-
ignimbrite (7)
-
rhyolite tuff (3)
-
tuff (7)
-
welded tuff (1)
-
-
rhyolites (12)
-
trachyandesites
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absarokite (1)
-
-
-
-
inclusions (1)
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intrusions (8)
-
isotopes
-
radioactive isotopes
-
Be-10/Be-9 (1)
-
Pb-206/Pb-204 (3)
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Pb-207/Pb-204 (2)
-
Pb-208/Pb-204 (2)
-
-
stable isotopes
-
Be-10/Be-9 (1)
-
C-13/C-12 (1)
-
He-4/He-3 (3)
-
Li-6 (1)
-
Li-7 (1)
-
Li-7/Li-6 (1)
-
Nd-144/Nd-143 (3)
-
O-18/O-16 (4)
-
Pb-206/Pb-204 (3)
-
Pb-207/Pb-204 (2)
-
Pb-208/Pb-204 (2)
-
Sr-87/Sr-86 (5)
-
-
-
lava (9)
-
magmas (22)
-
mantle (22)
-
Mesozoic
-
Cretaceous
-
Upper Cretaceous (2)
-
-
-
metal ores
-
gold ores (2)
-
mercury ores (1)
-
uranium ores (1)
-
zinc ores (1)
-
-
metals
-
alkali metals
-
lithium
-
Li-6 (1)
-
Li-7 (1)
-
Li-7/Li-6 (1)
-
-
rubidium (1)
-
-
alkaline earth metals
-
barium (1)
-
beryllium
-
Be-10/Be-9 (1)
-
-
strontium
-
Sr-87/Sr-86 (5)
-
-
-
iron (1)
-
lead
-
Pb-206/Pb-204 (3)
-
Pb-207/Pb-204 (2)
-
Pb-208/Pb-204 (2)
-
-
rare earths
-
neodymium
-
Nd-144/Nd-143 (3)
-
-
yttrium (1)
-
-
-
metamorphic rocks
-
eclogite (2)
-
-
metamorphism (1)
-
metasomatism (5)
-
meteorites
-
stony meteorites
-
chondrites (1)
-
-
-
Mexico
-
Baja California Mexico (1)
-
Sierra Madre Occidental (1)
-
-
mineral deposits, genesis (2)
-
noble gases
-
helium
-
He-4/He-3 (3)
-
-
-
North America
-
Basin and Range Province
-
Great Basin (5)
-
-
North American Cordillera (1)
-
Rocky Mountains
-
Northern Rocky Mountains (1)
-
U. S. Rocky Mountains
-
Absaroka Range
-
Beartooth Mountains (1)
-
-
San Juan Mountains (1)
-
-
-
Yakutat Terrane (1)
-
-
Ocean Drilling Program
-
Leg 170
-
ODP Site 1039 (1)
-
ODP Site 1040 (1)
-
-
-
ocean floors (1)
-
Oceania
-
Polynesia
-
Hawaii
-
Hawaii County Hawaii
-
Hawaii Island
-
Hualalai (1)
-
Kilauea (2)
-
Kohala (1)
-
Mauna Kea (1)
-
-
-
Mauna Loa (1)
-
-
Samoa (1)
-
-
-
orogeny (1)
-
oxygen
-
O-18/O-16 (4)
-
-
Pacific Coast (2)
-
Pacific Ocean
-
East Pacific
-
Northeast Pacific (1)
-
-
North Pacific
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Northeast Pacific (1)
-
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West Pacific
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Ontong Java Plateau (1)
-
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-
paleoclimatology (1)
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paleogeography (3)
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paleomagnetism (6)
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Paleozoic (1)
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petroleum (1)
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phase equilibria (1)
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plate tectonics (21)
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Precambrian
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Archean (1)
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upper Precambrian
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Proterozoic
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Neoproterozoic (1)
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-
-
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remote sensing (1)
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sedimentary rocks
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clastic rocks (1)
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sedimentation (1)
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sediments
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clastic sediments
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alluvium (1)
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South America
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Chile (1)
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spectroscopy (2)
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sulfur (1)
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tectonics
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neotectonics (2)
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thermal waters (1)
-
United States
-
Alaska
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Katmai (1)
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Katmai National Park (1)
-
-
Arizona
-
Coconino County Arizona
-
Meteor Crater (1)
-
-
-
California
-
Contra Costa County California (1)
-
Mono County California
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Long Valley Caldera (5)
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Mono Craters (1)
-
-
Northern California (3)
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San Francisco Bay region (1)
-
-
Colorado (1)
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Colorado Plateau (2)
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Columbia Plateau (1)
-
Great Basin (5)
-
Hawaii
-
Hawaii County Hawaii
-
Hawaii Island
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Hualalai (1)
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Kilauea (2)
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Kohala (1)
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Mauna Kea (1)
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Mauna Loa (1)
-
-
Idaho
-
Bingham County Idaho (1)
-
Blaine County Idaho (2)
-
Bonneville County Idaho (2)
-
Butte County Idaho (1)
-
Clark County Idaho (1)
-
Custer County Idaho (1)
-
Elmore County Idaho (1)
-
Idaho County Idaho (1)
-
Idaho National Laboratory (1)
-
Jefferson County Idaho (1)
-
Madison County Idaho (1)
-
Minidoka County Idaho (1)
-
Snake River plain (24)
-
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Yellowstone Hot Spot
Petrologic constraints on the origin of Proterozoic ferroan granites of the Laurentian margin
ABSTRACT Ferroan granite is a characteristic rock type of the Laurentian margin. It is commonly associated with anorthosite and related rocks. Ferroan granites are strongly enriched in iron, are alkalic to alkali-calcic, and are generally metaluminous. These geochemical characteristics reflect their tholeiitic parental magma source and relatively reducing and anhydrous conditions of crystallization. Their compositions distinguish them from arc magmas, which are magnesian and calcic to calc-alkalic. Ferroan granite magmas are hot, which promotes partial melting of their crustal wall rocks. Assimilation of these silica-rich and peraluminous melts drives the resulting magmas to higher silica and aluminum saturation values. Where Proterozoic ferroan granites intrude Archean crust, their mantle component is readily identified isotopically, but this is more difficult where they intrude relatively juvenile crust. Ferroan granite forms in tectonic environments that allow partial melts of tholeiitic mantle to pond and differentiate at or near the base of the crust. Phanerozoic examples occur in plume settings, such as the Snake River Plain and Yellowstone, or under certain conditions involving slab rollback, such as those that formed the Cenozoic topaz rhyolites of the western United States or ferroan rhyolites of the Sierra Madre Occidental. It is possible that the long-lived supercontinent Nuna-Rodinia, of which Laurentia was a part, formed an insulating lid that raised underlying mantle temperatures and created a unique environment that enabled emplacement of large volumes of mafic melt at the base of the crust. Ascent of felsic differentiates accompanied by variable crustal assimilation may have created large volumes of Proterozoic ferroan granite and related rocks.
Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot
Removal of the Northern Paleo-Teton Range along the Yellowstone Hotspot Track
ABSTRACT We present a tephrochronologic/chronostratigraphic database for the Mount Diablo area and greater San Francisco Bay region that provides a spatial and temporal framework for geologic studies in the region, including stratigraphy, paleogeography, tectonics, quantification of earth surface processes, recurrence of natural hazards, and climate change. We identified and correlated 34 tephra layers within this region using the chemical composition of their volcanic glasses, stratigraphic sequence, and isotopic and other dating techniques. Tephra layers range in age from ca. 65 ka to ca. 29 Ma, as determined by direct radiometric techniques or by correlation to sites where they have been dated. The tephra layers are of Quaternary or Neogene age except for two that are of Oligocene age. We correlated the tephra layers among numerous sites throughout northern California. Source areas of the tephra layers are the Snake River–Yellowstone hotspot trend of northern Nevada, southern Idaho, and western Wyoming; the Nevadaplano caldera complex of central Nevada; the Jemez Mountains–Valles Caldera in northwestern New Mexico; the Southern Nevada volcanic field and related source areas in eastern California and west-central Nevada; the Quien Sabe–Sonoma volcanic centers of the California Coast Ranges; and the young Cascade Range volcanic centers of northeastern California and Oregon.