un  search
Unalaska Island  search
BTUnited States
 .Alaska
 ..Southwestern Alaska
 ...Aleutian Islands
 ....Unalaska Island
NTMakushin
SNIn Fox Islands, Aleutian Islands, SW Alaska. Added to Thesaurus in 1989.
uncertainty  search
RTerrors
 geostatistics
 probability
 reliability
 statistical analysis
SNAlso index specific type of analysis if applicable. Added to Thesaurus in 1998.
UNCLOS  search
USELaw of the Sea
Uncompahgre Plateau  search
USEUncompahgre Uplift
Uncompahgre Uplift  search
BTUnited States
 .Uncompahgre Uplift
UFUncompahgre Plateau
RTNew Mexico
 Utah
 Colorado
 Paradox Basin
SNIndexed with states as applicable. Added to Thesaurus in 1989.
unconfined aquifers  search
BTaquifers
 .unconfined aquifers
RTground water
 shallow depth
 water table
 shallow aquifers
 surficial aquifers
unconformities  search
NTangular unconformities
 erosional unconformities
UFunconformity
RTstratigraphy
 hardground
 exhumation
 sequence stratigraphy
 lithostratigraphy
 stratigraphic gaps
unconformity  search
USEunconformities
unconformity-type deposits  search
RTmineral deposits, genesis
 uranium ores
unconsolidated materia  search
unconsolidated materials  search
RTcoarse-grained materials
 compactness
 consolidation
 fines
 materials
 particulate materials
 sediments
 soil mechanics
 soils
SNBefore 1978, search unconsolidated.
UNCTAD  search
UFUnited Nations Conference on Trade and Development
RTassociations
 economics
 international cooperation
 United Nations
SNAcronym. Usually out-of-scope for GeoRef. Added to Thesaurus in 1981.
und  search
Unda Russian Federation  search
BTCommonwealth of Independent States
 .Russian Federation
 ..Chita Russian Federation
 ...Unda Russian Federation
SNVillage in S Chita Oblast in Transbaikalia. Before 1993, Unda Russian Republic was also used. This term has multiple hierarchies.
undation  search
RTcrust
 crustal thickening
 tectonics
underclay  search
UFcoal clay
 root clay
 seat clay
 seat earth
 underearth
RTclay
 fireclay
 coal seams
underearth  search
USEunderclay
underground  search
SNA valid term through 1977. After 1977, use underground space.
underground cavities  search
RTcaverns
 caves
 solution cavities
 geomorphology
 underground space
 volcanic features
SNUse solution cavities if applicable. Also see underground space for engineering geology. Added to Thesaurus in 1993.
underground channels  search
RTchannels
 drainage
 infiltration galleries
 irrigation
 ground water
 underground installations
 waterways
SNAdded to Thesaurus in 1981.
underground disposal  search
UFunderground waste disposal
RTwaste disposal
 radioactive waste
 waste disposal sites
 waste management
 underground installations
 landfills
 far-field
 near-field
 underground storage
 underground storage tanks
SNAdded to Thesaurus in 1985.
underground installations  search
UFinstallations, underground
RTmines
 land subsidence
 seismic response
 rock mechanics
 permafrost
 geologic hazards
 seepage
 design
 construction
 feasibility studies
 foundations
 excavations
 pipelines
 leaking underground storage tanks
 far-field
 near-field
 gas storage
 oil storage
 site explora
SNUsed for geological studies on underground cavities (natural or otherwise), excluding tunnels.
underground mines  search
USEunderground mining
underground mining  search
BTmining
 .underground mining
UFsubsurface mining
 underground mines
RTmines
 mining geology
 cut-and-fill mining
 longwall mining
 underground installations
 roof control
SNAdded to Thesaurus in 1982.
Underground Research Laboratory  search
RTLac du Bonnet Batholith
 Pinawa Manitoba
 waste disposal
SNCanada's URL is located at (N50#DG15'W095#DG50'), about 10 kilometers north of Pinawa Manitoba, Whiteshell Research Area, W end of Whiteshell Provincial Park. In the Lac du Bonnet Batholith, it is site of nuclear waste disposal investigations. May occur i
underground space  search
UFspace, underground
RTland use
 underground cavities
 underground installations
 underground storage
underground storage  search
UFsubsurface storage
RTwaste disposal
 underground installations
 storage
 leaking underground storage tanks
 far-field
 near-field
 underground disposal
 gas storage
 oil storage
 underground storage tanks
 high-level waste
 low-level waste
 Stripa region
 underground space
SNAdded to Thesaurus in 1982.
underground storage tanks  search
RTgas storage
 gasoline
 leaking underground storage tanks
 oil storage
 petroleum products
 storage
 underground disposal
 underground storage
 waste disposal
SNUse leaking underground storage tanks if applicable. Added to Thesaurus in 1995.
underground streams  search
RTcaverns
 caves
 exsurgence
 hydrogeology
 hydrology
 karst
 resurgence
 springs
 streams
 tributaries
 geomorphology
 ground water
 unsaturated zone
SNAdded to Thesaurus in 1982.
underground waste disposal  search
USEunderground disposal
underground water  search
USEground water
Underhill Formation  search
RTLower Cambrian
 Neoproterozoic
 Vermont
SNIndexed with ages as applicable. Added to Thesaurus in 1989.
underplating  search
UFsubcretion
RTextension tectonics
 plate tectonics
 rifting
 accretionary wedges
 active margins
 subduction zones
 lithosphere
 continental crust
 oceanic crust
 underthrust faults
SNUsed to refer to different concepts in plate tectonics: In areas of rifting and thinning of continental crust, used to describe emplacement of basaltic magma at the base of the continental crust. In oceanic subduction zones, used to refer to accretion of
underpressure  search
RTfluid pressure
 hydrostatic pressure
 pore pressure
 pressure
 reservoir properties
underthrust faults  search
BTfaults
 .underthrust faults
RTunderplating
SNBefore 1978, search underthrust AND faults.
UNDP  search
UFUnited Nations Development Programme
RTassociations
 United Nations
SNAdded to Thesaurus in 1981.
undulatory extinction  search
RTmicroscope methods
 optical extinction
SNAdded to Thesaurus in 1981.
Ungava  search
BTCanada
 .Ungava
UFNew Quebec
RTQuebec
 Labrador
 New Quebec Crater
SNRegion including Quebec N of Eastmain River and SW Labrador. Indexed with Labrador and/or Quebec as applicable.
Ungava Crater  search
USENew Quebec Crater
Ungulata  search
BTChordata
 .Vertebrata
 ..Tetrapoda
 ...Mammalia
 ....Theria
 .....Eutheria
 ......Ungulata
RTCondylarthra
 Amblypoda
 Artiodactyla
 Perissodactyla
 Dinocerata
 Litopterna
 Pantodonta
 Pyrotheria
 Xenungulata
SNInformal group name for the hoofed mammals. Includes Amblypoda, Artiodactyla, Condylarthra, Dinocerata, Litopterna, Pantodonta, Perissodactyla, Pyrotheria, and Xenungulata.
uniaxial tests  search
RTbiaxial tests
 testing
 triaxial tests
 engineering geology
SNBefore 1978, search uniaxial.
Unicoi County Tennessee  search
BTUnited States
 .Tennessee
 ..Unicoi County Tennessee
UNIDO  search
UFUnited Nations Industrial Development Organization
RTassociations
 United Nations
SNAdded to Thesaurus in 1981.
uniformitarianism  search
UFactualism
RTsedimentation
 deposition
 biologic evolution
 stratigraphy
 geology
 catastrophism
 creationism
 history
Union County Arkansas  search
BTUnited States
 .Arkansas
 ..Union County Arkansas
SNS Arkansas.
Union County Florida  search
BTUnited States
 .Florida
 ..Union County Florida
SNN Florida.
Union County Georgia  search
BTUnited States
 .Georgia
 ..Union County Georgia
SNN Georgia.
Union County Illinois  search
BTUnited States
 .Illinois
 ..Union County Illinois
SNS Illinois.
Union County Indiana  search
BTIndiana
 .Union County Indiana
SNE Indiana.
Union County Iowa  search
BTUnited States
 .Iowa
 ..Union County Iowa
SNS Iowa.
Union County Kentucky  search
BTUnited States
 .Kentucky
 ..Union County Kentucky
SNW Kentucky.
Union County Mississippi  search
BTUnited States
 .Mississippi
 ..Union County Mississippi
SNN Mississippi.
Union County New Jersey  search
BTUnited States
 .New Jersey
 ..Union County New Jersey
RTWatchung Mountains
Union County New Mexico  search
BTUnited States
 .New Mexico
 ..Union County New Mexico
RTPasamonte Meteorite
SNExtreme NE New Mexico.
Union County North Carolina  search
BTUnited States
 .North Carolina
 ..Union County North Carolina
SNS North Carolina.
Union County Ohio  search
BTUnited States
 .Ohio
 ..Union County Ohio
SNCentral Ohio.
Union County Oregon  search
BTUnited States
 .Oregon
 ..Union County Oregon
RTWallowa Mountains
SNNE Oregon.
Union County Pennsylvania  search
BTUnited States
 .Pennsylvania
 ..Union County Pennsylvania
SNCentral Pennsylvania.
Union County South Carolina  search
BTUnited States
 .South Carolina
 ..Union County South Carolina
SNN South Carolina.
Union County South Dakota  search
BTUnited States
 .South Dakota
 ..Union County South Dakota
SNSE South Dakota.
Union County Tennessee  search
BTUnited States
 .Tennessee
 ..Union County Tennessee
SNNE Tennessee.
Union Islands  search
USETokelau
Union of Soviet Socialist Republics  search
SNNot a valid GeoRef index term after 1968. See USSR or Commonwealth of Independent States.
Union Parish Louisiana  search
BTUnited States
 .Louisiana
 ..Union Parish Louisiana
Unionidae  search
BTInvertebrata
 .Mollusca
 ..Bivalvia
 ...Unionidae
unit cell  search
UFcell, unit
RTcrystal structure
 crystal systems
 lattice
 lattice parameters
United Arab Emirates  search
BTAsia
 .Arabian Peninsula
 ..United Arab Emirates
NTAbu Dhabi
 Ajman
 Dubai
 Fujairah
 Ras al-Khaimah
 Sharjah
 Umm al-Qaiwain
UFTrucial Coast
 Trucial Oman
RTHanifa Formation
 Khuff Formation
 Shuaiba Formation
 Arab Formation
 Middle East
 Near East
 Semail Ophiolite
 Thamama Group
SNFederation of 7 states which was achieved in 1972. Formerly known as Trucial States, Trucial Oman, or Trucial Coast. Not strictly equivalent to Trucial Coast, but replaces Trucial Coast.
United Kingdom  search
BTEurope
 .Western Europe
 ..United Kingdom
NTGreat Britain
 Isle of Man
 Northern Ireland
RTAberystwyth Grits
 British Virgin Islands
 Ballantrae Complex
 Speeton Clay
 Barton Beds
 Barwell Meteorite
 Bembridge Marls
 British Geological Survey
 Skiddaw Slates
 London Clay
 Lower Greensand
 Sherwood Sandstone
 Oxford Clay
 Penrhyn Slate
 Shap Granite
 Upper Old
SNComprising Great Britain and Northern Ireland. Indexed with political divisions as applicable.
United Nations  search
RTassociations
 International Monetary Fund
 UNCTAD
 UNDP
 UNIDO
 World Bank
United Nations Conference on Trade and Development  search
USEUNCTAD
United Nations Convention on the Law of the Sea  search
USELaw of the Sea
United Nations Development Programme  search
USEUNDP
United Nations Industrial Development Organization  search
USEUNIDO
United States  search
NTAbsaroka Fault
 Alabama
 Alamosa River
 Alaska
 Albuquerque Basin
 Allegheny Front
 Allegheny Mountains
 Allegheny Plateau
 Amargosa Desert
 Amite River
 Anacostia River basin
 Anadarko Basin
 Ardmore Basin
 Arizona
 Arkansas
 Arkansas River
 Arkansas River valley
 Arkoma Basin
 Atlantic Coastal Plain
 Battle Mountain High
 Benton Uplift
 Big Blue River
 Bighorn Basin
 Bighorn River
 Black Warrior Basin
 Bloody Bluff Fault
 Blue Ridge Mountains
 Book Cliffs
 Brevard Zone
 Bronson Hill Anticlinorium
 California
 Cambridge Arch
 Canadian River
 Carolina Bays
 Carolina Terrane
 Carson River
 Cascade Range
 Catskill Delta
 Cedar Creek Anticline
 Central Basin Platform
 Chadron Arch
 Charlotte Belt
 Chattahoochee River
 Chemung River
 Chesapeake Bay
 Cheyenne Belt
 Chicot Aquifer
 Choptank River
 Cincinnati Arch
 Clark's Fork Basin
 Coeur d'Alene mining district
 Colorado
 Colorado Lineament
 Colorado Plateau
 Columbia Plateau
 Columbia River estuary
 Connecticut
 Connecticut River
 Connecticut Valley
 Coronado National Forest
 Crawford Thrust
 Culpeper Basin
 Dan River basin
 Delaware
 Delaware Basin
 Delaware Bay
 Delaware River
 Delaware River basin
 Delmarva Peninsula
 Denver Basin
 Dinosaur National Monument
 District of Columbia
 Dunbarton Basin
 Dunkard Basin
 Eastern U.S.
 Evangeline Aquifer
 Florida
 Floridan Aquifer
 Forest City Basin
 Four Corners
 Gallatin Range
 Genesee River
 Georgia
 Gettysburg Basin
 Gila River
 Great Basin
 Great Smoky Fault
 Great Smoky Mountains
 Hardeman Basin
 Hawaii
 Hayesville Fault
 Hayfork Terrane
 High Plains Aquifer
 Hudson River
 Hudson Valley
 Hueco Mountains
 Hugoton Embayment
 Hurricane Ridge Syncline
 Idaho
 Idaho Batholith
 Illinois
 Illinois Basin
 Iowa
 Ismay Zone
 Kansas
 Kentucky
 Kings Mountain Belt
 Kiokee Belt
 Kirkwood-Cohansey Aquifer
 Klamath Mountains
 Lake Char Fault
 Lake Chatuge
 Lake Powell
 Lake Tahoe
 Lewis and Clark Lineament
 Little Missouri River basin
 Llano Estacado
 Louisiana
 Madison Aquifer
 Magothy Aquifer
 Maine
 Maryland
 Massachusetts
 Maumee River valley
 Merrimack River valley
 Merrimack Synclinorium
 Michigan
 Midcontinent
 Midcontinent geophysical anomaly
 Middle Atlantic Bight
 Midwest
 Minnesota
 Mississippi
 Mississippi Embayment
 Mississippi River
 Mississippi Sound
 Mississippi Valley
 Missouri
 Missouri Plateau
 Missouri River
 Missouri River valley
 Mohave Mountains
 Montana
 Monticello Reservoir
 Mount Adams
 Moxa Arch
 Mullen Creek-Nash Fork shear zone
 Narragansett Basin
 Nashville Dome
 Navajo Indian Reservation
 Nebraska
 Nemaha Ridge
 Neosho River valley
 Nevada
 New England
 New Hampshire
 New Jersey
 New Madrid region
 New Mexico
 New York
 Newark Basin
 Newark-Gettysburg Basin
 North Carolina
 North Dakota
 Ogallala Aquifer
 Ohio
 Ohio River
 Ohio River basin
 Ohio River valley
 Okefenokee Swamp
 Oklahoma
 Oregon
 Orogrande Basin
 Ouachita Belt
 Ouachita Mountains
 Owyhee Mountains
 Ozark Mountains
 Palo Duro Basin
 Paradox Basin
 Pecos River
 Pecos River valley
 Pennsylvania
 Permian Basin
 Pilot Range
 Pine Mountain Window
 Potomac River
 Potomac River basin
 Powder River basin
 Pulaski thrust sheet
 Raft River
 Ramapo Fault
 Rangeley Lakes
 Raritan Bay
 Reading Prong
 Reelfoot Rift
 Rhode Island
 Rock Creek Park
 Sabine Uplift
 Saco River
 Salisbury Embayment
 Savannah River
 Selway-Bitterroot Wilderness
 Sevier orogenic belt
 Shenandoah Valley
 South Carolina
 South Dakota
 South Platte River
 South Platte River valley
 Southern Oklahoma Aulacogen
 Southern U.S.
 Southwestern U.S.
 Susquehanna River
 Susquehanna River basin
 Suwannee River
 Tennessee
 Tennessee River
 Tennessee Valley
 Texas
 Tombigbee River
 Trans-Pecos
 Truckee River
 U. S. Rocky Mountains
 Uinta Basin
 Uncompahgre Uplift
 Utah
 Verdigris River valley
 Vermont
 Virgin River valley
 Virginia
 Walker Lane
 Wasatch fault zone
 Wasatch Front
 Washakie Basin
 Washington
 Washita River valley
 West Virginia
 Western U.S.
 Wiggins Arch
 Wisconsin
 Wyoming
 Wyoming Province
 Yakima fold belt
 Yellowstone National Park
 Yellowstone River
RTAMCOR
 Appalachians
 Avalon
SNBetween 1978-1997, Pacific Coast was used as a narrower term.
United States Exclusive Economic Z  search
United States Exclusive Economic Zone  search
UFU.S. Exclusive Economic Zone
RTUnited States
 ocean floors
 economics
 Gulf of Mexico
 North Pacific
 North Atlantic
 offshore
 mineral exploration
 exploration
 policy
 Law of the Sea
 Exclusive Economic Zone
 strategic minerals
SNBefore 1985, also search EEZ or Exclusive Economic Zone AND United States. Added to Thesaurus in 1985.
United States Geological Survey  search
USEU. S. Geological Survey
units, stratigraphic  search
USEstratigraphic units
univariate analysis  search
BTstatistical analysis
 .univariate analysis
RTanalysis
 bivariate analysis
 multivariate analysis
SNAdded to Thesaurus in 1989.
Universal Soil Loss Equation  search
UFUSLE
RTerosion
 soils
 equations
 mathematical methods
 runoff
 soil erosion
 erodibility
SNAdded to Thesaurus in 1989.
universal stage  search
UFFedorov stage
 stage, universal
 U-stage
RTstructural analysis
 microscope methods
 ore microscopy
universities  search
USEacademic institutions
University of Arizona  search
RTacademic institutions
 Arizona
SNIn Tucson.
University of Bonn  search
RTacademic institutions
 Germany
SNIn Bonn, North Rhine-Westphalia.
University of California  search
RTacademic institutions
 Los Alamos National Laboratory
 California
SNHas geoscience departments located in Berkeley, Davis, Los Angeles, Riverside, San Diego, Santa Barbara and Santa Cruz.
University of Cambridge  search
USECambridge University
University of Louvain  search
RTacademic institutions
 Belgium
SNIn Louvain E of Brussels.
University of Lund  search
RTacademic institutions
 Sweden
SNIn Lund, Malmohus, extreme S Sweden.
University of Michigan  search
RTacademic institutions
 Michigan
SNIn Ann Arbor W of Detroit.
University of Pennsylvania  search
RTacademic institutions
 Pennsylvania
SNIn Philadelphia.
University of Rome  search
RTacademic institutions
 Italy
SNIn Rome.
University of Tokyo  search
UFTokyo Imperial University
RTacademic institutions
 Japan
SNIn Tokyo.
University of Wisconsin  search
RTacademic institutions
 Wisconsin
SNHas geoscience departments located in Madison, Eau Claire, Green Bay, Wausau (Marathon County campus), Milwaukee, Oshkosh, Kenosha (Parkside campus), Platteville, River Falls, Stevens Point, Superior and Whitewater.
Unkar Group  search
BTChronostratigraphic Units
 .Precambrian
 ..Unkar Group
RTArizona
SNGrand Canyon Series. Divided into (descending) Dox Sandstone, Shinumo Quartzite, Hakatai Shale, Bass Limestone, and Hotuata Conglomerate. In N Arizona.
unmixing  search
USEexsolution
unsaturated zone  search
UFnon-saturated zone
 vadose zone
 zone of aeration
RTsoils
 ground water
 hydrogeology
 SUTRA
 preferential flow
 capillary water
 saturated zone
 water table
 underground streams
 water regimes
 Green-Ampt model
 DRAINMOD
 infiltration
 Richards equation
SNSubsurface zone with pressure less than atmospheric. In GeoRef, it is not considered ground water. Added to Thesaurus in 1981.
Unst  search
BTEurope
 .Western Europe
 ..United Kingdom
 ...Great Britain
 ....Scotland
 .....Shetland Islands
 ......Unst
SNNorthernmost large island of the Shetland Islands. This term has multiple hierarchies.
unsteady flow  search
UFtransient flow
RThydrology
 hydrodynamics
 hydraulics
 fluid dynamics
 radial flow
 steady flow
SNAdded to Thesaurus in 1982.
Unstrut River  search
BTEurope
 .Central Europe
 ..Germany
 ...Unstrut River
RTSaxony-Anhalt Germany
 Thuringia Germany
SNTributary of the Saale River. Also search Unstrut. Indexed with states as applicable.
Unzen  search
BTAsia
 .Far East
 ..Japan
 ...Kyushu
 ....Nagasaki Japan
 .....Unzen
UFUnzen Volcano
RTvolcanoes
SNActive volcano. In Unzen National Park, Nagasaki Prefecture on central Shimabar Peninsula E of Nagasaki.
Unzen Volcano  search
USEUnzen