tr  search
trace elements  search
UFguest element
 microelement
 trace-elements
RTnutrients
 chemical elements
 thermal waters
 rare earths
 major elements
 minor elements
 trace-element analyses
 trace metals
trace fossils  search
SNA valid term through 1972. After 1972, use ichnofossils. However, as of 1981, a distinction is made between ichnofossils and lebensspuren. Use lebensspuren when the emphasis is sedimentary petrology; use ichnofossils for paleontologic studies.
trace metals  search
RTenvironmental geology
 metals
 pollution
 trace elements
 geochemistry
SNMay be used with commodities (list C).
trace-element analyses  search
RTanalysis
 chemical analysis
 chemical elements
 major-element analyses
 minor-element analyses
 particle-induced X-ray emission
 spectroscopy
 trace elements
 voltammetry
SNFor data, see appropriate material.
trace-elements  search
USEtrace elements
tracers  search
RTbreakthrough curves
 chlorofluorocarbons
 chloroform
 D/H
 dye tracers
 fluorimetry
 ground water
 hydrogeology
 hydrology
 image analysis
 isotopes
 radioactive tracers
 radioactivity
 surface water
tracheophyte  search
SNAs of 1993, use vascular taxa AND Plantae.
trachyandesites  search
BTigneous rocks
 .volcanic rocks
 ..trachyandesites
NTlatite
trachybasalts  search
BTigneous rocks
 .volcanic rocks
 ..basalts
 ...alkali basalts
 ....trachybasalts
RTbenmoreite
 trachydolerite
trachydolerite  search
BTigneous rocks
 .volcanic rocks
 ..basalts
 ...alkali basalts
 ....trachydolerite
RTtrachybasalts
Trachyleberididae  search
BTInvertebrata
 .Arthropoda
 ..Mandibulata
 ...Crustacea
 ....Ostracoda
 .....Podocopida
 ......Cytherocopina
 .......Cytheracea
 ........Trachyleberididae
UFTrachyleberidinae
SNThis term has multiple hierarchies.
Trachyleberidinae  search
USETrachyleberididae
trachyte-phonolite family  search
SNAs of 1981, no longer a valid term for GeoRef. Use trachytes or phonolites as applicable.
trachytes  search
BTigneous rocks
 .volcanic rocks
 ..trachytes
NTkeratophyre
 quartz keratophyre
SNBefore 1981, search trachyte-phonolite family.
tracks  search
RTbiogenic structures
 ichnofossils
 lebensspuren
 sedimentary structures
 trails
SNBefore 1977, also search tracks and trails. Includes use as the sedimentary structure as well as the paleontologic feature. Also index ichnofossils OR lebensspuren if applicable. See lists F and K.
tracks and trails  search
SNNot a valid index term for GeoRef after 1971. Used in subfiles E, N, T, and B. Use tracks or trails as separate terms.
Tracy Arm  search
BTUnited States
 .Alaska
 ..Tracy Arm
RTSoutheastern Alaska
SNSE Alaska. Added to Thesaurus in 1989.
Tradewater Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Carboniferous
 ....Pennsylvanian
 .....Middle Pennsylvanian
 ......Tradewater Formation
RTKentucky
SNW Kentucky. Added to Thesaurus in 1985.
Traill County North Dakota  search
BTUnited States
 .North Dakota
 ..Traill County North Dakota
trails  search
RTbiogenic structures
 ichnofossils
 lebensspuren
 sedimentary structures
 tracks
SNBefore 1977, also search tracks and trails. Includes use as the sedimentary structure as well as the paleontologic feature. Also index ichnofossils OR lebensspuren if applicable. See lists F and K.
Tranquillity Base  search
USETaurus-Littrow
Trans Alaska Crustal Transect  search
USETACT
Trans-Alaska Crustal Transect  search
USETACT
Trans-Alaska Pipeline  search
BTUnited States
 .Alaska
 ..Trans-Alaska Pipeline
RTSouthern Alaska
 Northern Alaska
 East-Central Alaska
 Valdez Alaska
SNPipeline constructed for the movement of crude oil from the North Slope at Prudhoe Bay on the Arctic Ocean in the NE to the port of Valdez off Prince William Sound in the SE. Indexed with Northern Alaska, East-Central Alaska and/or Southern Alaska as appl
Trans-Amazonian Orogeny  search
USETransamazonian Orogeny
Trans-Aravalli Vindhyan Basin  search
BTAsia
 .Indian Peninsula
 ..India
 ...Trans-Aravalli Vindhyan Basin
RTRajasthan India
 Madhya Pradesh India
SNIndexed with states as applicable.
Trans-Hudsonian Orogeny  search
USEHudsonian Orogeny
Trans-Jordan  search
USEJordan
Trans-Pecos  search
BTUnited States
 .Trans-Pecos
RTNew Mexico
 Texas
 West Texas
 Marathon Geosyncline
SNRegion W of the Pecos River and E of the Rio Grande in West Texas and S central New Mexico. Indexed with states as applicable.
Transamazonian Orogeny  search
BTChronostratigraphic Units
 .Precambrian
 ..Proterozoic
 ...Paleoproterozoic
 ....Transamazonian Orogeny
UFAmazonian Orogeny
 Trans-Amazonian Orogeny
RTorogeny
 Brazil
 Pan-African Orogeny
 Bolivia
 South America
 Venezuela
 Guyana
 Surinam
SNPrimarily in NE and north-central South America. Also search Transamazonian Cycle if applicable. Added to Thesaurus in 1998.
Transantarctic Mountains  search
BTAntarctica
 .Transantarctic Mountains
RTQueen Alexandra Range Meteorites
SNA series of mountain ranges extending across the continent from the Filchner Ice Shelf on the Atlantic Ocean side through Victoria Land on the Pacific Ocean side separating East Antarctica from West Antarctica.
Transbaikal  search
USETransbaikalia
Transbaikalia  search
BTCommonwealth of Independent States
 .Russian Federation
 ..Transbaikalia
BTAsia
 .Transbaikalia
UFTransbaikal
RTArgun River
 Amur Russian Federation
 Zeya River
 Buryat Russian Federation
 Baikal region
 Chita Russian Federation
 Western Transbaikalia
SNRegion of SE Siberia E of Lake Baikal including Buryatia; and Chita and Amur oblasts. This term has multiple hierarchies.
Transcarpathia Ukraine  search
BTEurope
 .Ukraine
 ..Transcarpathia Ukraine
NTBeregovo Ukraine
 Borkut Deposit
 Rakhov Ukraine
RTRussian Platform
 Rakhov Massif
SNThis term has multiple hierarchies.
Transcaucasia  search
BTEurope
 .Transcaucasia
UFTranscaucasus
RTGeorgian Republic
 Armenia
 Azerbaijan
 Lesser Caucasus
 Greater Caucasus
 Caucasus
 Kabardin-Balkar Russian Federation
SNRegion including Armenia, Azerbaijan and the Georgian Republic. Indexed with former Soviet republics as applicable.
Transcaucasus  search
USETranscaucasia
Transcontinental Arch  search
BTNorth America
 .Transcontinental Arch
RTCanada
 United States
 Mexico
 Great Plains
 Midcontinent
SNProminent Middle Ordovician feature extending from the Canadian Shield, southwest across the Great Plains to NW Mexico. Indexed with states, countries, or regions as applicable. Added to Thesaurus in 1993.
transcurrent faults  search
BTfaults
 .transcurrent faults
RTdisplacements
 transtension
 strike-slip faults
 transverse faults
SNBefore 1978, also search faults AND transcurrent.
Transdanubia  search
BTngary
 .Transdanubia
NTCentral Transdanubia
 Northwestern Transdanubia
 Southeastern Transdanubia
 Southern Transdanubia
UFDunantul
SNFertile, hilly region between the Danube River and the Austrian border.
Transdanubian Central Mountains  search
USEBakony Mountains
transducers  search
RTdata processing
 instruments
 pressuremeters
SNAlso search pressure transducers or pressure sensors if applicable.
transects  search
USEgeotraverses
transfer faults  search
BTfaults
 .strike-slip faults
 ..transfer faults
RTaccommodation zones
 transform faults
 dip-slip faults
 fault zones
SNAdded to Thesaurus in 1993.
transfer functions  search
RTdata processing
 functions
 mathematical geology
 mathematical methods
 mathematical models
SNAdded to Thesaurus in 1985.
transfer, heat  search
USEheat transfer
transfer, mass  search
USEmass transfer
transform  search
SNA valid term through 1977. After 1977, use transform faults.
transform faults  search
BTfaults
 .strike-slip faults
 ..transform faults
RTaccommodation zones
 plate tectonics
 transfer faults
 mid-ocean ridges
 displacements
 transtension
 fracture zones
 Rivera Ocean Seismic Experiment
SNBefore 1978, also search faults AND transform.
transformations  search
RTclay mineralogy
 crystal chemistry
 metabolism
 minerals
 ocean waves
 phase equilibria
 phase transitions
 soils
SNBefore 1978, transformation was used under ocean waves.
transformations, Laplace  search
USELaplace transformations
transgression  search
BTsea-level changes
 .transgression
RTstratigraphy
 paleogeography
 levels
 Fischer plots
 submergence
 regression
 highstands
 lake-level changes
SNAs of 1998, restricted to use for seas.
transient electromagnetic logging  search
SNUse transient methods and electromagnetic logging.
transient electromagnetic methods  search
SNUse transient methods and electromagnetic methods.
transient electromagnetic response  search
SNUse transient methods and electromagnetic methods or electromagnetic logging as applicable.
transient flow  search
USEunsteady flow
transient methods  search
RTelectromagnetic logging
 electromagnetic methods
 geophysical methods
 transient phenomena
SNIncludes use with electromagnetic methods or electromagnetic logging for transient electromagnetic response. Added to Thesaurus in 1981.
transient phenomena  search
UFphenomena, transient
RTtransient methods
 steady-state processes
SNAdded to Thesaurus in 1985.
transition  search
SNA valid general term through 1977.
transition zones  search
UFzones, transition
RT410-km discontinuity
 mantle
 670-km discontinuity
 plate tectonics
 phase transitions
 crust
 continental crust
 core
 core-mantle boundary
 wadsleyite
 oceanic crust
translation lattice  search
USElattice
transmissibility  search
USEtransmissivity
transmission  search
SNA valid term through 1978. After 1993, use transmission electron microscopy or TEM data if applicable.
transmission electron microscopy  search
RTchemical analysis
 electron microscopy
 scanning electron microscopy
 SEM data
SNFor the method. Before 1993 also search (transmission OR transmission method) AND electron microscopy. Added to Thesaurus in 1993.
transmission electron microscopy data  search
USETEM data
transmission method  search
SNNo longer a valid term for GeoRef. See transmission electron microscopy.
transmissivity  search
UFcoefficient of transmissibility
 transmissibility
RTground water
 aquifers
 hydrogeology
 permeability
 hydrology
 preferential flow
 hydraulic conductivity
 slug tests
SNRestricted to usage in relation to hydrology. Not to be used for remote sensing.
transport  search
UFentrainment
RThydrophobic materials
 solute transport
 pollutants
 atmospheric transport
 SUTRA
 magma transport
 marine transport
 sediment transport
 stream transport
 migration
 deflation
 hydrodynamics
 chemical dispersion
 movement
 hydraulics
 settling
 glacial transport
 wave di
SNAs of 1995, use with pollutants for pollution studies. Before 1995, also search movement with pollutants or specific type of pollutant. See specific types: atmospheric transport, chemical dispersion or wave dispersion, glacial transport, marine transport,
transportation  search
RTpipelines
SNAs of 1978, term is restricted to non-geological meaning.
transpression  search
RTcompression tectonics
 crustal shortening
 faults
 orogeny
 structural analysis
 plate tectonics
 tectonics
SNAdded to Thesaurus in 1989.
transtension  search
RTextension tectonics
 mid-ocean ridges
 neotectonics
 oblique-slip faults
 sea-floor spreading
 spreading centers
 strike-slip faults
 tension
 transcurrent faults
 transform faults
 tectonics
SNAdded to Thesaurus in 1995.
Transvaal region  search
BTAfrica
 .Southern Africa
 ..South Africa
 ...Transvaal region
UFTransvaal South Africa
RTBarberton greenstone belt
 Fig Tree Series
 Mpumalanga South Africa
 Limpopo Basin
 Bushveld Complex
 Guateng South Africa
 Merensky Reef
 North-West Province South Africa
 Northern Province South Africa
 Klerksdorp Field
 Lebombo Mountains
 Swartkrans Cave
 Vaal Riv
SNFormer province in NE South Africa which was split in the mid-1990's to form E part of North-West Province, and Northern Province, Mpumalanga, and Guateng provinces. After 1993, also search individual provinces. Indexed with provinces as applicable.
Transvaal South Africa  search
USETransvaal region
Transvaal Supergroup  search
BTChronostratigraphic Units
 .Precambrian
 ..Transvaal Supergroup
RTSouth Africa
 Pretoria Group
 Malmani Subgroup
transverse faults  search
BTfaults
 .transverse faults
RTorientation
 transcurrent faults
SNBefore 1978, also search faults AND transverse.
transverse folds  search
USEsuperposed folds
transverse isotropy  search
RTanisotropic materials
 anisotropy
 isotropy
 layered materials
 seismology
 velocity
Transverse Ranges  search
BTUnited States
 .California
 ..Transverse Ranges
RTNorthridge earthquake 1994
 San Gabriel Mountains
 San Bernardino Mountains
SNIn S California. Indexed with counties as applicable.
transverse wave  search
USES-waves
Transylvania  search
BTEurope
 .Southern Europe
 ..Romania
 ...Transylvania
NTAlba-Iulia Romania
 Almas Valley basin
 Aries Valley
 Baraolt Basin
 Baraolt Romania
 Beius Basin
 Bihor Mountains
 Bihor Romania
 Bistrita Romania
 Brad Romania
 Brasov Romania
 Calimani Mountains
 Cluj Romania
 Covasna Romania
 Crisana-Maramures
 Gurghiu Mountains
 Harghita Mountains
 Harghita Romania
 Hateg Romania
 Maramures Romania
 Muntii Metalici
 Mures Romania
 Padurea Craiului Mountains
 Persani Mountains
 Petrosani Basin
 Poiana-Rusca Mountains
 Retezat Mountains
 Rodna Mountains
 Rodna Romania
 Salaj Romania
 Satu Mare Romania
 Sebes Mountains
 Sebes Romania
 Sibiu Romania
 Simleu Basin
 Transylvanian Basin
RTGetic Nappe
 Transylvanian Alps
 Fagaras Mountains
 Jiu River valley
 Olt River
 Olt River valley
SNRegion bounded by the Carpathians on the E and the Transylvanian Alps on the S, in central and NW Romania.
Transylvania Basin  search
USETransylvanian Basin
Transylvania County North Carolina  search
BTUnited States
 .North Carolina
 ..Transylvania County North Carolina
Transylvanian Alps  search
BTEurope
 .Southern Europe
 ..Romania
 ...Transylvanian Alps
NTVulcan Mountains
UFSouth Carpathians
 Southern Carpathians
RTTransylvania
 Getic Nappe
 Carpathians
 Walachia
 Bucegi Mountains
 Paring Mountains
 Rodna Mountains
 Fagaras Mountains
 Retezat Mountains
SNContinuation of the Carpathians extending E-W in central Romania. Indexed with region as applicable.
Transylvanian Basin  search
BTEurope
 .Southern Europe
 ..Romania
 ...Transylvania
 ....Transylvanian Basin
UFTransylvania Basin
 Transylvanian Plain
SNPrimarily a plateau.
Transylvanian Plain  search
USETransylvanian Basin
trap rock  search
USEtrap rocks
trap rocks  search
BTigneous rocks
 .volcanic rocks
 ..basalts
 ...trap rocks
UFtrap rock
RTaggregate
 construction materials
 diabase
SNFor petroleum and natural gas, use traps if applicable.
Trap Spring Field  search
BTUnited States
 .Nevada
 ..Nye County Nevada
 ...Trap Spring Field
RToil and gas fields
SNOil field in central Nevada. Added to Thesaurus in 1981.
Trapani Italy  search
BTEurope
 .Southern Europe
 ..Italy
 ...Sicily Italy
 ....Trapani Italy
SNProvince in W Sicily.
trapped particles  search
SNAs of 1993, no longer a valid term for GeoRef. Usually out-of-scope. Used with magnetosphere.
traps  search
NTstratigraphic traps
 structural traps
RTnatural gas
 oil and gas fields
 petroleum
 petroleum accumulation
Tras-os-Montes  search
BTEurope
 .Southern Europe
 ..Iberian Peninsula
 ...Portugal
 ....Tras-os-Montes
RTBraganca Portugal
 Vila Real Portugal
SNFormer province in NE Portugal. Now it comprises Braganca and Vila Real districts. Indexed with districts as applicable.
Travale  search
USETravale Field
Travale Field  search
BTEurope
 .Southern Europe
 ..Italy
 ...Tuscany Italy
 ....Travale Field
UFTravale
RTgeothermal fields
SNGeothermal field in Tuscany, W Italy. Added to Thesaurus in 1989.
travel time  search
USEtraveltime
traveltime  search
UFtravel time
RTseismology
 elastic waves
 dip moveout
 moveout
 normal moveout
 short-period waves
 long-period waves
 traveltime curves
traveltime curves  search
UFcurves, traveltime
 hodographs
RTseismology
 elastic waves
 traveltime
traveltime residuals  search
RTseismology
SNAdded to Thesaurus in 1981.
Traverse County Minnesota  search
BTUnited States
 .Minnesota
 ..Traverse County Minnesota
Traverse Group  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Devonian
 ....Traverse Group
RTMichigan
SNMiddle and Upper Devonian. Comprises (ascending) Belle Shale, Rockport Quarry Limestone, Ferron Point Shale, Genshaw Formation, Koehler Limestone, Gravel Point Formation, and Beebe School Formation. In S Michigan.
traverses  search
USEgeotraverses
travertine  search
BTsedimentary rocks
 .carbonate rocks
 ..travertine
UFcalc-sinter
 calcareous sinter
RTcalcite
 limestone
 chemically precipitated rocks
 tufa
 carbonate sediments
Travis County Texas  search
BTUnited States
 .Texas
 ..Travis County Texas
NTAustin Texas
RTBarton Springs
 Edwards Aquifer
SNS Central Texas.
Travis Peak Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Cretaceous
 ....Lower Cretaceous
 .....Travis Peak Formation
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Cretaceous
 ....Comanchean
 .....Travis Peak Formation
RTTexas
 Trinity Group
SNIn Trinity Group. S and E Texas. This term has multiple hierarchies. Added to Thesaurus in 1989.
Treasure County Montana  search
BTUnited States
 .Montana
 ..Treasure County Montana
treatment  search
SNAs of 1985, no longer a valid term for GeoRef. See soil treatment; water treatment.
tree rings  search
UFannual growth rings
 dendrochronology
 rings, tree
RTgeochronology
 relative age
trees  search
RTdrainage patterns
 forests
 networks
SNAs of 1993, use tree rings, wood or fossil wood for geochronology. Use geobotanical methods for mineral exploration and Plantae for paleobotany or stratigraphy studies, respectively. This term is primarily used for ecology studies (Note added 1995.). Adde
Trego County Kansas  search
BTUnited States
 .Kansas
 ..Trego County Kansas
SNW central Kansas.
Tremadoc Bay  search
BTEurope
 .Western Europe
 ..United Kingdom
 ...Great Britain
 ....Wales
 .....Tremadoc Bay
RTMerionethshire Wales
 Caernarvonshire Wales
SNInlet of Saint Georges Channel in Gwynedd County in NW Wales.
Tremadocian  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Lower Ordovician
 .....Tremadocian
NTHalifax Formation
RTSan Juan Formation
SNEurope. Above Dolgellian (Cambrian), below Arenigian.
tremolite  search
BTsilicates
 .chain silicates
 ..amphibole group
 ...clinoamphibole
 ....tremolite
Tremp Spain  search
BTEurope
 .Southern Europe
 ..Iberian Peninsula
 ...Spain
 ....Catalonia Spain
 .....Lerida Spain
 ......Tremp Spain
SNTown in Catalonia in W Lerida, NE Spain.
Trempealeau County Wisconsin  search
BTUnited States
 .Wisconsin
 ..Trempealeau County Wisconsin
Trempealeauan  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Cambrian
 ....Upper Cambrian
 .....Trempealeauan
SNNorth America. Upper Cambrian, above Franconian, below Lower Ordovician.
trenches  search
UFmarginal trench
 oceanic trench
 sea-floor trench
RTbottom features
 ocean floors
 plate tectonics
 subduction zones
 island arcs
 troughs
 fore-arc basins
 morphostructures
 Benioff zone
 subduction
 furrows
trenching  search
RTdrainage
 dredging
 drilling
 erosion
 excavations
 hydrology
 pipelines
 sampling
 site exploration
 soil sampling
 engineering geology
 water erosion
SNAdded to Thesaurus in 1995.
trend analysis  search
USEtrend-surface analysis
trend surface analysis  search
USEtrend-surface analysis
trend-surface analysis  search
BTstatistical analysis
 .trend-surface analysis
UFtrend analysis
 trend surface analysis
RTanalysis
 data processing
Trent  search
SNNot a valid term for GeoRef. See Trento Italy or Trent Valley.
Trent Valley  search
RTEngland
 North Carolina
 Ontario
SNRiver valley in central England, SE North Carolina, and SE Ontario. Also search Trent. Indexed with England, North Carolina, or Ontario as applicable.
Trentino  search
BTEurope
 .Southern Europe
 ..Italy
 ...Trentino-Alto Adige Italy
 ....Trentino
RTAlto Adige
SNS part of Trentino-Alto Adige autonomous region.
Trentino-Alto Adige Italy  search
BTEurope
 .Southern Europe
 ..Italy
 ...Trentino-Alto Adige Italy
NTAlto Adige
 Bolzano Italy
 Cima d'Asta
 Latemar Massif
 Predazzo Italy
 Trentino
 Trento Italy
 Valsugana
UFVenezia-Tridentina
RTDolomites
 Marmolada Glacier
 Tauern Window
 Venetia
 Otztal Alps
 Zillertal Alps
SNAutonomous region in NE Italy. Formerly Venezia-Tridentina.
Trento Italy  search
BTEurope
 .Southern Europe
 ..Italy
 ...Trentino-Alto Adige Italy
 ....Trento Italy
RTTyrol Austria
SNProvince and city in S Trentino-Alto Adige.
Trenton Group  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Middle Ordovician
 .....Trentonian
 ......Trenton Group
RTVirginia
 Ohio
 Pennsylvania
 Vermont
 New York
 Georgia
 Michigan
SNStandard section of group comprises (ascending) Rockland Limestone, Hull Formation, Sherman Fall Formation, Cobourg Formation, Collingwood Shale, and Gloucester Shale. In Georgia, Michigan, N Ohio, New York, Vermont, and W Virginia.
Trenton New Jersey  search
BTUnited States
 .New Jersey
 ..Mercer County New Jersey
 ...Trenton New Jersey
SNCity on the Delaware River in W New Jersey.
Trentonian  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Middle Ordovician
 .....Trentonian
NTTrenton Group
RTChamplainian
SNNorth America. Upper Mohawkian, above Blackriverian.
Trepca Mine  search
BTEurope
 .Southern Europe
 ..Yugoslavia
 ...Serbia
 ....Kosovo-Metohija Yugoslavia
 .....Trepca Mine
UFTrepcha Mine
RTmines
 lead-zinc deposits
 Kopaonik
SNLead-zinc deposits. Mining district in the Kosovo region of S Serbia. Also search Trepca.
Trepcha Mine  search
USETrepca Mine
Trepostomata  search
BTInvertebrata
 .Bryozoa
 ..Trepostomata
Treutlen County Georgia  search
BTUnited States
 .Georgia
 ..Treutlen County Georgia
trevorite  search
BToxides
 .trevorite
RTiron oxides
tria  search
Trialet Range  search
BTEurope
 .Georgian Republic
 ..Trialet Range
BTEurope
 .Caucasus
 ..Lesser Caucasus
 ...Trialet Range
SNN mountain range of the Lesser Caucasus in central Georgian Republic. Also search Trialet or Trialeti. This term has multiple hierarchies.
triangle zones  search
UFzones, triangle
RTtectonics
 decollement
 fold and thrust belts
 forelands
 thrust faults
triangulation  search
RTcartography
 geodesy
 geodetic networks
 geotraverses
 neotectonics
 surveys
 trilateration
 very long baseline interferometry
Triassic  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Triassic
NTLower Triassic
 Middle Triassic
 Upper Triassic
 Andalusian
 Chanares Formation
 Cordevolian
 Fremouw Formation
 Hallstatt Limestone
 Hawkesbury Sandstone
 Ipswich Coal Measures
 Moenkopi Formation
 Narrabeen Group
 Nicola Group
 Red Peak Formation
 Sherwood Sandstone
 Shublik Formation
 Takla Group
 Wetterstein Limestone
RTDwyka Formation
 Karroo Supergroup
 Alleghany Orogeny
 Beacon Supergroup
 Baskunchak Series
 Beaufort Group
 Botucatu Formation
 Estrada Nova Formation
 Cache Creek Group
 Chugwater Formation
 Glen Canyon Group
 Gondwana System
 Indosinian Orogeny
 Khorat Group
 Korene
SNAbove Permian (of Paleozoic), below Jurassic.
triaxial tests  search
RTbiaxial tests
 confining pressure
 deformation
 rock mechanics
 soil mechanics
 testing
 uniaxial tests
triazines  search
BTpesticides
 .herbicides
 ..triazines
NTatrazine
 cyanazine
 metribuzin
 simazine
UFs-triazines
RTagrochemicals
 pollutants
SNAlso search s-triazine. Added to Thesaurus in 1995.
tributaries  search
RTdrainage basins
 drainage patterns
 fluvial features
 glacial geology
 glaciers
 rivers
 rivers and streams
 stream capture
 stream order
 streams
 geomorphology
 underground streams
 valleys
 watersheds
SNAdded to Thesaurus in 1993.
Triceratops  search
BTChordata
 .Vertebrata
 ..Tetrapoda
 ...Reptilia
 ....Diapsida
 .....Archosauria
 ......Ornithischia
 .......Ceratopsia
 ........Ceratopsidae
 .........Triceratops
SNGenus. Also search Agathaumas. This term has multiple hierarchies.
Trichinopoly India  search
USETiruchirapalli India
trichloroethane  search
BTorganic compounds
 .halogenated hydrocarbons
 ..chlorinated hydrocarbons
 ...trichloroethane
RTDDT
 ethane
SNSometimes a parent compound of DDT. Added to Thesaurus in 1989.
trichloroethene  search
USEtrichloroethylene
trichloroethylene  search
BTorganic compounds
 .halogenated hydrocarbons
 ..chlorinated hydrocarbons
 ...trichloroethylene
UFtrichloroethene
RTethylene
SNProduced from heating tetrachloroethane with hydrated lime. Sometimes abbreviated TCE. Added to Thesaurus in 1989.
trichloromethane  search
USEchloroform
Trichoptera  search
BTInvertebrata
 .Arthropoda
 ..Mandibulata
 ...Insecta
 ....Pterygota
 .....Neoptera
 ......Endopterygota
 .......Trichoptera
SNOrder. Caddis flies.
triclinic  search
USEtriclinic system
triclinic system  search
BTcrystal systems
 .triclinic system
UFtriclinic
RTcrystallography
SNBefore 1985, also search triclinic. Added to Thesaurus in 1985.
Triconodonta  search
BTChordata
 .Vertebrata
 ..Tetrapoda
 ...Mammalia
 ....Triconodonta
SNOrder.
Tridacna  search
BTInvertebrata
 .Mollusca
 ..Bivalvia
 ...Tridacna
SNGenus.
tridymite  search
BTsilicates
 .framework silicates
 ..silica minerals
 ...tridymite
RTcristobalite
 opal-CT
Trieste Italy  search
BTEurope
 .Southern Europe
 ..Italy
 ...Friuli-Venezia Giulia Italy
 ....Trieste Italy
RTDinaric Alps
SNCity at head of the Adriatic Sea on Gulf of Trieste in SE Friuli-Venezia Giulia, NE Italy.
Trigg County Kentucky  search
BTUnited States
 .Kentucky
 ..Trigg County Kentucky
triggering  search
SNNot a valid term for GeoRef. Use causes if applicable.
Trigonia  search
BTInvertebrata
 .Mollusca
 ..Bivalvia
 ...Trigoniidae
 ....Trigonia
SNGenus.
Trigoniidae  search
BTInvertebrata
 .Mollusca
 ..Bivalvia
 ...Trigoniidae
NTTrigonia
trilate  search
trilateration  search
RTcartography
 geodesy
 geodetic coordinates
 leveling
 triangulation
SNAdded to Thesaurus in 1985.
Trilobita  search
BTInvertebrata
 .Arthropoda
 ..Trilobitomorpha
 ...Trilobita
NTAgnostida
 Corynexochida
 Lichida
 Odontopleurida
 Phacopida
 Ptychopariida
 Redlichiida
RTCrustacea
 Cruziana
 Rusophycus
 Trilobitoidea
SNClass.
Trilobitoidea  search
BTInvertebrata
 .Arthropoda
 ..Trilobitomorpha
 ...Trilobitoidea
RTTrilobita
SNClass.
Trilobitomorpha  search
BTInvertebrata
 .Arthropoda
 ..Trilobitomorpha
NTTrilobita
 Trilobitoidea
Trilophosauria  search
BTChordata
 .Vertebrata
 ..Tetrapoda
 ...Reptilia
 ....Diapsida
 .....Trilophosauria
RTAraeoscelidia
SNIncludes the family Trilophosauridae. As of 1993, considered a narrower term of Archosauromorpha.
Trimble County Kentucky  search
BTUnited States
 .Kentucky
 ..Trimble County Kentucky
Trinidad  search
BTCaribbean region
 .West Indies
 ..Antilles
 ...Lesser Antilles
 ....Trinidad and Tobago
 .....Trinidad
RTCarapita Formation
 Northern Range
SNIsland off NE coast of Venezuela in the Lesser Antilles. Major part of independent state of Trinidad and Tobago.
Trinidad and Tobago  search
BTCaribbean region
 .West Indies
 ..Antilles
 ...Lesser Antilles
 ....Trinidad and Tobago
NTTobago
 Trinidad
RTNorthern Range
SNComprises the islands of Trinidad and Tobago, Atlantic Ocean, off NE coast of Venezuela.
Trinity Complex  search
BTUnited States
 .California
 ..Trinity Complex
RTKlamath Mountains
 Trinity County California
 Shasta County California
 Siskiyou County California
SNKlamath Mountains, N California. Also search Trinity AND (ophiolite or peridotites) if applicable. Indexed with county as applicable. Added to Thesaurus in 1993.
Trinity County California  search
BTUnited States
 .California
 ..Trinity County California
RTEel River
 Trinity River
 Trinity Complex
SNN California.
Trinity County Texas  search
BTUnited States
 .Texas
 ..Trinity County Texas
SNE Texas.
Trinity Group  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Cretaceous
 ....Lower Cretaceous
 .....Trinity Group
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Cretaceous
 ....Comanchean
 .....Trinity Group
RTLouisiana
 Oklahoma
 Texas
 Antlers Sands
 Arkansas
 Glen Rose Formation
 Paluxy Formation
 Pearsall Formation
 Rodessa Formation
 Travis Peak Formation
SNLower Cretaceous. Subdivided into (ascending) Pearsall, Rodessa, Ferry Lake, and Rusk time-stratigraphic units. In SW Arkansas, NW Louisiana, central S and SE Oklahoma, and Texas. This term has multiple hierarchies.
Trinity River  search
RTHumboldt County California
 Trinity County California
 California
 Texas
 Trinity River basin
SNFlows into Trinity Bay off Galveston Bay on the Gulf of Mexico in E Texas. Also a river in Humboldt and Trinity counties, NW California. Search Trinity River in combination with appropriate state. Indexed with states and counties as applicable.
Trinity River basin  search
RTTrinity River
 California
 Texas
SNE Texas and NW California. Search in combination with appropriate state. Indexed with states as applicable. Added to Thesaurus in 1989.
triphylite  search
BTphosphates
 .triphylite
triple junctions  search
RTChile Margin Triple Junction
 Mendocino fracture zone
 plate geometry
 Rodriguez triple junction
 plate tectonics
triplite  search
BThalides
 .fluorides
 ..triplite
BTphosphates
 .triplite
SNThis term has multiple hierarchies.
tripoli  search
BTsedimentary rocks
 .tripoli
RTabrasives
 diatomite
 limestone
 chert
 diatomaceous earth
SNNot to be used for diatomaceous earth or diatomite. For use as a commodity, see abrasives in list C. Added to Thesaurus in 1995.
Tripoli Libya  search
BTAfrica
 .North Africa
 ..Libya
 ...Tripoli Libya
SNCity on the Mediterranean Sea in NW Libya.
Tripolis Greece  search
BTEurope
 .Southern Europe
 ..Greece
 ...Peloponnesus Greece
 ....Tripolis Greece
RTGavrovo Zone
SNCity in central Peloponnesus, S Greece.
Tripolitania  search
BTAfrica
 .North Africa
 ..Libya
 ...Tripolitania
RTGarian Libya
SNNW part of country which was a province until 1963. Under the Italians, it was a major province covering the entire W part of colony.
tripolite  search
USEdiatomaceous earth
Tripp County South Dakota  search
BTUnited States
 .South Dakota
 ..Tripp County South Dakota
Tripura India  search
BTAsia
 .Indian Peninsula
 ..India
 ...Northeastern India
 ....Tripura India
RTBengal
SNState E of Bangladesh in NE India.
Tristan da Cunha  search
BTAtlantic Ocean Islands
 .Tristan da Cunha
NTGough Island
UFTristan da Cunha Islands
RTSaint Helena
SNA group of 5 British volcanic islands in the central South Atlantic Ocean. Also the name of the main island of the group. Dependencies of Saint Helena.
Tristan da Cunha Islands  search
USETristan da Cunha
triterpanes  search
BTorganic compounds
 .hydrocarbons
 ..triterpanes
NTgammacerane
 hopanoids
 oleananes
RTbiomarkers
 diterpanes
 terpanes
SNAdded to Thesaurus in 1985.
triterpenoids  search
BTorganic compounds
 .isoprenoids
 ..triterpenoids
RTbiomarkers
SNAdded to Thesaurus in 1995.
Triticites  search
BTmicrofossils
 .Fusulinina
 ..Fusulinidae
 ...Triticites
NTTriticites ventricosus
SNGenus. This term has multiple hierarchies.
Triticites ventricosus  search
BTmicrofossils
 .Fusulinina
 ..Fusulinidae
 ...Triticites
 ....Triticites ventricosus
SNThis term has multiple hierarchies.
tritium  search
BTisotopes
 .radioactive isotopes
 ..tritium
BThydrogen
 .tritium
UFH-3
RTabsolute age
SNThis term has multiple hierarchies.
Triton Satellite  search
RTicy satellites
 Neptune
 Nereid Satellite
 satellites
 Voyager Program
SNOne of satellites of Neptune. Before 1989, also search Triton AND Neptune. Added to Thesaurus in 1989.
Trivandrum India  search
BTAsia
 .Indian Peninsula
 ..India
 ...Kerala India
 ....Trivandrum India
SNKerala, SW India.
TRM  search
USEthermoremanent magnetization
Trochammina  search
BTInvertebrata
 .Protista
 ..Foraminifera
 ...Textulariina
 ....Lituolacea
 .....Trochammina
RTmicrofossils
SNGenus. Indexed with microfossils if applicable.
troctolite  search
BTigneous rocks
 .plutonic rocks
 ..gabbros
 ...troctolite
Troia  search
USETroy
troilite  search
BTsulfides
 .troilite
RTmeteorites
 pyrrhotite
Troja  search
USETroy
Troll Field  search
BTAtlantic Ocean
 .North Atlantic
 ..North Sea
 ...Troll Field
RToil and gas fields
 giant fields
SNGiant field, Horda Platform, 60 km offshore Norway, NE North Sea.
Trompia Valley  search
BTEurope
 .Southern Europe
 ..Italy
 ...Lombardy Italy
 ....Trompia Valley
SNValley of upper Mella River in E Lombardy, N Italy.
Troms Norway  search
BTEurope
 .Western Europe
 ..Scandinavia
 ...Norway
 ....Troms Norway
NTLyngen Peninsula
RTVesteralen
 Lapland
SNCounty in far N Norway.
trona  search
BTcarbonates
 .trona
RTsodium carbonate
 Searles Lake
SNMay be used as a commodity term with sodium carbonate.
Trona California  search
BTUnited States
 .California
 ..San Bernardino County California
 ...Trona California
RTSearles Lake
SNVillage in Mojave Desert of S California.
Trondelag  search
BTEurope
 .Western Europe
 ..Scandinavia
 ...Norway
 ....Trondelag
RTNord-Trondelag Norway
 Sor-Trondelag Norway
SNRegion in central part of country between Norwegian Sea and Swedish border around Trondheim Fjord. Indexed with counties as applicable.
Trondheim Norway  search
BTEurope
 .Western Europe
 ..Scandinavia
 ...Norway
 ....Sor-Trondelag Norway
 .....Trondheim Norway
SNCity on the Norwegian Sea.
trondhjemite  search
BTigneous rocks
 .plutonic rocks
 ..diorites
 ...trondhjemite
RTplagiogranite
Troodos Massif  search
BTAsia
 .Middle East
 ..Cyprus
 ...Troodos Massif
UFTroodos Mountain
 Troodos Mountains
RTAgrokipia Deposit
 Troodos Ophiolite
SNMountainous mass SW of Nicosia which includes Mount Troodos, the highest peak on the island.
Troodos Mountain  search
USETroodos Massif
Troodos Mountains  search
USETroodos Massif
Troodos Ophiolite  search
RTAgrokipia Deposit
 Cyprus
 Middle East
 Troodos Massif
SNAdded to Thesaurus in 1989.
trophic analysis  search
RTbiomass
 carnivorous taxa
 communities
 diet
 ecology
 ecosystems
 feeding
 nutrition
 paleoecology
 paleontology
 predation
SNAdded to Thesaurus in 1985.
tropical  search
SNA valid term through 1977. After 1977, use tropical environment.
tropical environment  search
RTclimate
 depositional environment
 ecology
 equatorial region
 paleoclimatology
 rain forests
 subtropical environment
SNBefore 1978, search tropical.
troposphere  search
RTatmosphere
 climate
 stratosphere
SNUsually out-of-scope. Used with atmosphere.
Trotus Valley  search
BTEurope
 .Moldavia
 ..Trotus Valley
BTEurope
 .Southern Europe
 ..Romania
 ...Trotus Valley
SNRiver valley SSW of Bacau in W Moldavia. Also search Trotus; Trotus River. This term has multiple hierarchies.
Trou Sans Fond  search
BTAtlantic Ocean
 .North Atlantic
 ..Trou Sans Fond
UFLe Trou Sans Fond
 Trou-Sans-Fond
RTsubmarine canyons
 Ivory Coast
SNSubmarine canyon off SW Nigeria in the Bight of Benin.
Trou-Sans-Fond  search
USETrou Sans Fond
troughs  search
RTaulacogens
 bottom features
 channels
 furrows
 gorges
 ocean floors
 trenches
Troup County Georgia  search
BTUnited States
 .Georgia
 ..Troup County Georgia
Trousdale County Tennessee  search
BTUnited States
 .Tennessee
 ..Trousdale County Tennessee
SNN Tennessee.
Troy  search
BTAsia
 .Middle East
 ..Turkey
 ...Troy
UFIlion
 Ilium
 Troia
 Troja
SNAncient ruined city. An archeological site, named Hissarlik, on the Menderes River S of the Dardanelles in NW Anatolia.
Trucial Coast  search
USEUnited Arab Emirates
SNA 350 mile section of S Persian Gulf littoral extending from Qatar to Ruus al Jubal. Often formerly used interchangeably with Trucial Oman and Trucial States.
Trucial Oman  search
USEUnited Arab Emirates
SNFormer name of 7 British protected states on the Trucial Coast.
Truckee River  search
BTUnited States
 .Truckee River
RTCalifornia
 Nevada
SNRises in Lake Tahoe in E California and flows NE and E into Pyramid Lake in NW Nevada. Also search Truckee. Indexed with counties and states as applicable.
Trujillo Venezuela  search
BTSouth America
 .Venezuela
 ..Trujillo Venezuela
RTLake Maracaibo
 Maracaibo Basin
SNState in NW Venezuela.
Trumbull County Ohio  search
BTUnited States
 .Ohio
 ..Trumbull County Ohio
SNNE Ohio.
Trust Territory of the Pacific Islands  search
SNNot a valid term for GeoRef. U.S. trust territory. As of 1993, see Micronesia, or Caroline Islands, Marshall Islands, or Mariana Islands for the Northern Mariana Islands as applicable.
Truth or Consequences New Mexico  search
BTUnited States
 .New Mexico
 ..Sierra County New Mexico
 ...Truth or Consequences New Mexico
SNTown in SW New Mexico.
Trypanites  search
BTichnofossils
 .Trypanites
SNGenus.