IODP SEDIS - Thesaurus -

tr

trace elements
UF	guest element
	microelement
	trace-elements
RT	nutrients
	chemical elements
	thermal waters
	rare earths
	major elements
	minor elements
	trace-element analyses
	trace metals

trace fossils
SN	A 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
RT	environmental geology
	metals
	pollution
	trace elements
	geochemistry
SN	May be used with commodities (list C).

trace-element analyses
RT	analysis
	chemical analysis
	chemical elements
	major-element analyses
	minor-element analyses
	particle-induced X-ray emission
	spectroscopy
	trace elements
	voltammetry
SN	For data, see appropriate material.

trace-elements
USE	trace elements

tracers
RT	breakthrough curves
	chlorofluorocarbons
	chloroform
	D/H
	dye tracers
	fluorimetry
	ground water
	hydrogeology
	hydrology
	image analysis
	isotopes
	radioactive tracers
	radioactivity
	surface water

tracheophyte
SN	As of 1993, use vascular taxa AND Plantae.

trachyandesites
BT	igneous rocks
	.volcanic rocks
	..trachyandesites
NT	latite

trachybasalts
BT	igneous rocks
	.volcanic rocks
	..basalts
	...alkali basalts
	....trachybasalts
RT	benmoreite
	trachydolerite

trachydolerite
BT	igneous rocks
	.volcanic rocks
	..basalts
	...alkali basalts
	....trachydolerite
RT	trachybasalts

Trachyleberididae
BT	Invertebrata
	.Arthropoda
	..Mandibulata
	...Crustacea
	....Ostracoda
	.....Podocopida
	......Cytherocopina
	.......Cytheracea
	........Trachyleberididae
UF	Trachyleberidinae
SN	This term has multiple hierarchies.

Trachyleberidinae
USE	Trachyleberididae

trachyte-phonolite family
SN	As of 1981, no longer a valid term for GeoRef. Use trachytes or phonolites as applicable.

trachytes
BT	igneous rocks
	.volcanic rocks
	..trachytes
NT	keratophyre
	quartz keratophyre
SN	Before 1981, search trachyte-phonolite family.

tracks
RT	biogenic structures
	ichnofossils
	lebensspuren
	sedimentary structures
	trails
SN	Before 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
SN	Not 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
BT	United States
	.Alaska
	..Tracy Arm
RT	Southeastern Alaska
SN	SE Alaska. Added to Thesaurus in 1989.

Tradewater Formation
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Carboniferous
	....Pennsylvanian
	.....Middle Pennsylvanian
	......Tradewater Formation
RT	Kentucky
SN	W Kentucky. Added to Thesaurus in 1985.

Traill County North Dakota
BT	United States
	.North Dakota
	..Traill County North Dakota

trails
RT	biogenic structures
	ichnofossils
	lebensspuren
	sedimentary structures
	tracks
SN	Before 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
USE	Taurus-Littrow

Trans Alaska Crustal Transect
USE	TACT

Trans-Alaska Crustal Transect
USE	TACT

Trans-Alaska Pipeline
BT	United States
	.Alaska
	..Trans-Alaska Pipeline
RT	Southern Alaska
	Northern Alaska
	East-Central Alaska
	Valdez Alaska
SN	Pipeline 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
USE	Transamazonian Orogeny

Trans-Aravalli Vindhyan Basin
BT	Asia
	.Indian Peninsula
	..India
	...Trans-Aravalli Vindhyan Basin
RT	Rajasthan India
	Madhya Pradesh India
SN	Indexed with states as applicable.

Trans-Hudsonian Orogeny
USE	Hudsonian Orogeny

Trans-Jordan
USE	Jordan

Trans-Pecos
BT	United States
	.Trans-Pecos
RT	New Mexico
	Texas
	West Texas
	Marathon Geosyncline
SN	Region 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
BT	Chronostratigraphic Units
	.Precambrian
	..Proterozoic
	...Paleoproterozoic
	....Transamazonian Orogeny
UF	Amazonian Orogeny
	Trans-Amazonian Orogeny
RT	orogeny
	Brazil
	Pan-African Orogeny
	Bolivia
	South America
	Venezuela
	Guyana
	Surinam
SN	Primarily in NE and north-central South America. Also search Transamazonian Cycle if applicable. Added to Thesaurus in 1998.

Transantarctic Mountains
BT	Antarctica
	.Transantarctic Mountains
RT	Queen Alexandra Range Meteorites
SN	A 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
USE	Transbaikalia

Transbaikalia
BT	Commonwealth of Independent States
	.Russian Federation
	..Transbaikalia
BT	Asia
	.Transbaikalia
UF	Transbaikal
RT	Argun River
	Amur Russian Federation
	Zeya River
	Buryat Russian Federation
	Baikal region
	Chita Russian Federation
	Western Transbaikalia
SN	Region of SE Siberia E of Lake Baikal including Buryatia; and Chita and Amur oblasts. This term has multiple hierarchies.

Transcarpathia Ukraine
BT	Europe
	.Ukraine
	..Transcarpathia Ukraine
NT	Beregovo Ukraine
	Borkut Deposit
	Rakhov Ukraine
RT	Russian Platform
	Rakhov Massif
SN	This term has multiple hierarchies.

Transcaucasia
BT	Europe
	.Transcaucasia
UF	Transcaucasus
RT	Georgian Republic
	Armenia
	Azerbaijan
	Lesser Caucasus
	Greater Caucasus
	Caucasus
	Kabardin-Balkar Russian Federation
SN	Region including Armenia, Azerbaijan and the Georgian Republic. Indexed with former Soviet republics as applicable.

Transcaucasus
USE	Transcaucasia

Transcontinental Arch
BT	North America
	.Transcontinental Arch
RT	Canada
	United States
	Mexico
	Great Plains
	Midcontinent
SN	Prominent 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
BT	faults
	.transcurrent faults
RT	displacements
	transtension
	strike-slip faults
	transverse faults
SN	Before 1978, also search faults AND transcurrent.

Transdanubia
BT	ngary
	.Transdanubia
NT	Central Transdanubia
	Northwestern Transdanubia
	Southeastern Transdanubia
	Southern Transdanubia
UF	Dunantul
SN	Fertile, hilly region between the Danube River and the Austrian border.

Transdanubian Central Mountains
USE	Bakony Mountains

transducers
RT	data processing
	instruments
	pressuremeters
SN	Also search pressure transducers or pressure sensors if applicable.

transects
USE	geotraverses

transfer faults
BT	faults
	.strike-slip faults
	..transfer faults
RT	accommodation zones
	transform faults
	dip-slip faults
	fault zones
SN	Added to Thesaurus in 1993.

transfer functions
RT	data processing
	functions
	mathematical geology
	mathematical methods
	mathematical models
SN	Added to Thesaurus in 1985.

transfer, heat
USE	heat transfer

transfer, mass
USE	mass transfer

transform
SN	A valid term through 1977. After 1977, use transform faults.

transform faults
BT	faults
	.strike-slip faults
	..transform faults
RT	accommodation zones
	plate tectonics
	transfer faults
	mid-ocean ridges
	displacements
	transtension
	fracture zones
	Rivera Ocean Seismic Experiment
SN	Before 1978, also search faults AND transform.

transformations
RT	clay mineralogy
	crystal chemistry
	metabolism
	minerals
	ocean waves
	phase equilibria
	phase transitions
	soils
SN	Before 1978, transformation was used under ocean waves.

transformations, Laplace
USE	Laplace transformations

transgression
BT	sea-level changes
	.transgression
RT	stratigraphy
	paleogeography
	levels
	Fischer plots
	submergence
	regression
	highstands
	lake-level changes
SN	As of 1998, restricted to use for seas.

transient electromagnetic logging
SN	Use transient methods and electromagnetic logging.

transient electromagnetic methods
SN	Use transient methods and electromagnetic methods.

transient electromagnetic response
SN	Use transient methods and electromagnetic methods or electromagnetic logging as applicable.

transient flow
USE	unsteady flow

transient methods
RT	electromagnetic logging
	electromagnetic methods
	geophysical methods
	transient phenomena
SN	Includes use with electromagnetic methods or electromagnetic logging for transient electromagnetic response. Added to Thesaurus in 1981.

transient phenomena
UF	phenomena, transient
RT	transient methods
	steady-state processes
SN	Added to Thesaurus in 1985.

transition
SN	A valid general term through 1977.

transition zones
UF	zones, transition
RT	410-km discontinuity
	mantle
	670-km discontinuity
	plate tectonics
	phase transitions
	crust
	continental crust
	core
	core-mantle boundary
	wadsleyite
	oceanic crust

translation lattice
USE	lattice

transmissibility
USE	transmissivity

transmission
SN	A valid term through 1978. After 1993, use transmission electron microscopy or TEM data if applicable.

transmission electron microscopy
RT	chemical analysis
	electron microscopy
	scanning electron microscopy
	SEM data
SN	For the method. Before 1993 also search (transmission OR transmission method) AND electron microscopy. Added to Thesaurus in 1993.

transmission electron microscopy data
USE	TEM data

transmission method
SN	No longer a valid term for GeoRef. See transmission electron microscopy.

transmissivity
UF	coefficient of transmissibility
	transmissibility
RT	ground water
	aquifers
	hydrogeology
	permeability
	hydrology
	preferential flow
	hydraulic conductivity
	slug tests
SN	Restricted to usage in relation to hydrology. Not to be used for remote sensing.

transport
UF	entrainment
RT	hydrophobic 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
SN	As 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
RT	pipelines
SN	As of 1978, term is restricted to non-geological meaning.

transpression
RT	compression tectonics
	crustal shortening
	faults
	orogeny
	structural analysis
	plate tectonics
	tectonics
SN	Added to Thesaurus in 1989.

transtension
RT	extension tectonics
	mid-ocean ridges
	neotectonics
	oblique-slip faults
	sea-floor spreading
	spreading centers
	strike-slip faults
	tension
	transcurrent faults
	transform faults
	tectonics
SN	Added to Thesaurus in 1995.

Transvaal region
BT	Africa
	.Southern Africa
	..South Africa
	...Transvaal region
UF	Transvaal South Africa
RT	Barberton 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
SN	Former 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
USE	Transvaal region

Transvaal Supergroup
BT	Chronostratigraphic Units
	.Precambrian
	..Transvaal Supergroup
RT	South Africa
	Pretoria Group
	Malmani Subgroup

transverse faults
BT	faults
	.transverse faults
RT	orientation
	transcurrent faults
SN	Before 1978, also search faults AND transverse.

transverse folds
USE	superposed folds

transverse isotropy
RT	anisotropic materials
	anisotropy
	isotropy
	layered materials
	seismology
	velocity

Transverse Ranges
BT	United States
	.California
	..Transverse Ranges
RT	Northridge earthquake 1994
	San Gabriel Mountains
	San Bernardino Mountains
SN	In S California. Indexed with counties as applicable.

transverse wave
USE	S-waves

Transylvania
BT	Europe
	.Southern Europe
	..Romania
	...Transylvania
NT	Alba-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
RT	Getic Nappe
	Transylvanian Alps
	Fagaras Mountains
	Jiu River valley
	Olt River
	Olt River valley
SN	Region bounded by the Carpathians on the E and the Transylvanian Alps on the S, in central and NW Romania.

Transylvania Basin
USE	Transylvanian Basin

Transylvania County North Carolina
BT	United States
	.North Carolina
	..Transylvania County North Carolina

Transylvanian Alps
BT	Europe
	.Southern Europe
	..Romania
	...Transylvanian Alps
NT	Vulcan Mountains
UF	South Carpathians
	Southern Carpathians
RT	Transylvania
	Getic Nappe
	Carpathians
	Walachia
	Bucegi Mountains
	Paring Mountains
	Rodna Mountains
	Fagaras Mountains
	Retezat Mountains
SN	Continuation of the Carpathians extending E-W in central Romania. Indexed with region as applicable.

Transylvanian Basin
BT	Europe
	.Southern Europe
	..Romania
	...Transylvania
	....Transylvanian Basin
UF	Transylvania Basin
	Transylvanian Plain
SN	Primarily a plateau.

Transylvanian Plain
USE	Transylvanian Basin

trap rock
USE	trap rocks

trap rocks
BT	igneous rocks
	.volcanic rocks
	..basalts
	...trap rocks
UF	trap rock
RT	aggregate
	construction materials
	diabase
SN	For petroleum and natural gas, use traps if applicable.

Trap Spring Field
BT	United States
	.Nevada
	..Nye County Nevada
	...Trap Spring Field
RT	oil and gas fields
SN	Oil field in central Nevada. Added to Thesaurus in 1981.

Trapani Italy
BT	Europe
	.Southern Europe
	..Italy
	...Sicily Italy
	....Trapani Italy
SN	Province in W Sicily.

trapped particles
SN	As of 1993, no longer a valid term for GeoRef. Usually out-of-scope. Used with magnetosphere.

traps
NT	stratigraphic traps
	structural traps
RT	natural gas
	oil and gas fields
	petroleum
	petroleum accumulation

Tras-os-Montes
BT	Europe
	.Southern Europe
	..Iberian Peninsula
	...Portugal
	....Tras-os-Montes
RT	Braganca Portugal
	Vila Real Portugal
SN	Former province in NE Portugal. Now it comprises Braganca and Vila Real districts. Indexed with districts as applicable.

Travale
USE	Travale Field

Travale Field
BT	Europe
	.Southern Europe
	..Italy
	...Tuscany Italy
	....Travale Field
UF	Travale
RT	geothermal fields
SN	Geothermal field in Tuscany, W Italy. Added to Thesaurus in 1989.

travel time
USE	traveltime

traveltime
UF	travel time
RT	seismology
	elastic waves
	dip moveout
	moveout
	normal moveout
	short-period waves
	long-period waves
	traveltime curves

traveltime curves
UF	curves, traveltime
	hodographs
RT	seismology
	elastic waves
	traveltime

traveltime residuals
RT	seismology
SN	Added to Thesaurus in 1981.

Traverse County Minnesota
BT	United States
	.Minnesota
	..Traverse County Minnesota

Traverse Group
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Devonian
	....Traverse Group
RT	Michigan
SN	Middle 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
USE	geotraverses

travertine
BT	sedimentary rocks
	.carbonate rocks
	..travertine
UF	calc-sinter
	calcareous sinter
RT	calcite
	limestone
	chemically precipitated rocks
	tufa
	carbonate sediments

Travis County Texas
BT	United States
	.Texas
	..Travis County Texas
NT	Austin Texas
RT	Barton Springs
	Edwards Aquifer
SN	S Central Texas.

Travis Peak Formation
BT	Chronostratigraphic Units
	.Phanerozoic
	..Mesozoic
	...Cretaceous
	....Lower Cretaceous
	.....Travis Peak Formation
BT	Chronostratigraphic Units
	.Phanerozoic
	..Mesozoic
	...Cretaceous
	....Comanchean
	.....Travis Peak Formation
RT	Texas
	Trinity Group
SN	In Trinity Group. S and E Texas. This term has multiple hierarchies. Added to Thesaurus in 1989.

Treasure County Montana
BT	United States
	.Montana
	..Treasure County Montana

treatment
SN	As of 1985, no longer a valid term for GeoRef. See soil treatment; water treatment.

tree rings
UF	annual growth rings
	dendrochronology
	rings, tree
RT	geochronology
	relative age

trees
RT	drainage patterns
	forests
	networks
SN	As 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
BT	United States
	.Kansas
	..Trego County Kansas
SN	W central Kansas.

Tremadoc Bay
BT	Europe
	.Western Europe
	..United Kingdom
	...Great Britain
	....Wales
	.....Tremadoc Bay
RT	Merionethshire Wales
	Caernarvonshire Wales
SN	Inlet of Saint Georges Channel in Gwynedd County in NW Wales.

Tremadocian
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Ordovician
	....Lower Ordovician
	.....Tremadocian
NT	Halifax Formation
RT	San Juan Formation
SN	Europe. Above Dolgellian (Cambrian), below Arenigian.

tremolite
BT	silicates
	.chain silicates
	..amphibole group
	...clinoamphibole
	....tremolite

Tremp Spain
BT	Europe
	.Southern Europe
	..Iberian Peninsula
	...Spain
	....Catalonia Spain
	.....Lerida Spain
	......Tremp Spain
SN	Town in Catalonia in W Lerida, NE Spain.

Trempealeau County Wisconsin
BT	United States
	.Wisconsin
	..Trempealeau County Wisconsin

Trempealeauan
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Cambrian
	....Upper Cambrian
	.....Trempealeauan
SN	North America. Upper Cambrian, above Franconian, below Lower Ordovician.

trenches
UF	marginal trench
	oceanic trench
	sea-floor trench
RT	bottom features
	ocean floors
	plate tectonics
	subduction zones
	island arcs
	troughs
	fore-arc basins
	morphostructures
	Benioff zone
	subduction
	furrows

trenching
RT	drainage
	dredging
	drilling
	erosion
	excavations
	hydrology
	pipelines
	sampling
	site exploration
	soil sampling
	engineering geology
	water erosion
SN	Added to Thesaurus in 1995.

trend analysis
USE	trend-surface analysis

trend surface analysis
USE	trend-surface analysis

trend-surface analysis
BT	statistical analysis
	.trend-surface analysis
UF	trend analysis
	trend surface analysis
RT	analysis
	data processing

Trent
SN	Not a valid term for GeoRef. See Trento Italy or Trent Valley.

Trent Valley
RT	England
	North Carolina
	Ontario
SN	River valley in central England, SE North Carolina, and SE Ontario. Also search Trent. Indexed with England, North Carolina, or Ontario as applicable.

Trentino
BT	Europe
	.Southern Europe
	..Italy
	...Trentino-Alto Adige Italy
	....Trentino
RT	Alto Adige
SN	S part of Trentino-Alto Adige autonomous region.

Trentino-Alto Adige Italy
BT	Europe
	.Southern Europe
	..Italy
	...Trentino-Alto Adige Italy
NT	Alto Adige
	Bolzano Italy
	Cima d'Asta
	Latemar Massif
	Predazzo Italy
	Trentino
	Trento Italy
	Valsugana
UF	Venezia-Tridentina
RT	Dolomites
	Marmolada Glacier
	Tauern Window
	Venetia
	Otztal Alps
	Zillertal Alps
SN	Autonomous region in NE Italy. Formerly Venezia-Tridentina.

Trento Italy
BT	Europe
	.Southern Europe
	..Italy
	...Trentino-Alto Adige Italy
	....Trento Italy
RT	Tyrol Austria
SN	Province and city in S Trentino-Alto Adige.

Trenton Group
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Ordovician
	....Middle Ordovician
	.....Trentonian
	......Trenton Group
RT	Virginia
	Ohio
	Pennsylvania
	Vermont
	New York
	Georgia
	Michigan
SN	Standard 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
BT	United States
	.New Jersey
	..Mercer County New Jersey
	...Trenton New Jersey
SN	City on the Delaware River in W New Jersey.

Trentonian
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Ordovician
	....Middle Ordovician
	.....Trentonian
NT	Trenton Group
RT	Champlainian
SN	North America. Upper Mohawkian, above Blackriverian.

Trepca Mine
BT	Europe
	.Southern Europe
	..Yugoslavia
	...Serbia
	....Kosovo-Metohija Yugoslavia
	.....Trepca Mine
UF	Trepcha Mine
RT	mines
	lead-zinc deposits
	Kopaonik
SN	Lead-zinc deposits. Mining district in the Kosovo region of S Serbia. Also search Trepca.

Trepcha Mine
USE	Trepca Mine

Trepostomata
BT	Invertebrata
	.Bryozoa
	..Trepostomata

Treutlen County Georgia
BT	United States
	.Georgia
	..Treutlen County Georgia

trevorite
BT	oxides
	.trevorite
RT	iron oxides

tria

Trialet Range
BT	Europe
	.Georgian Republic
	..Trialet Range
BT	Europe
	.Caucasus
	..Lesser Caucasus
	...Trialet Range
SN	N mountain range of the Lesser Caucasus in central Georgian Republic. Also search Trialet or Trialeti. This term has multiple hierarchies.

triangle zones
UF	zones, triangle
RT	tectonics
	decollement
	fold and thrust belts
	forelands
	thrust faults

triangulation
RT	cartography
	geodesy
	geodetic networks
	geotraverses
	neotectonics
	surveys
	trilateration
	very long baseline interferometry

Triassic
BT	Chronostratigraphic Units
	.Phanerozoic
	..Mesozoic
	...Triassic
NT	Lower 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
RT	Dwyka 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
SN	Above Permian (of Paleozoic), below Jurassic.

triaxial tests
RT	biaxial tests
	confining pressure
	deformation
	rock mechanics
	soil mechanics
	testing
	uniaxial tests

triazines
BT	pesticides
	.herbicides
	..triazines
NT	atrazine
	cyanazine
	metribuzin
	simazine
UF	s-triazines
RT	agrochemicals
	pollutants
SN	Also search s-triazine. Added to Thesaurus in 1995.

tributaries
RT	drainage basins
	drainage patterns
	fluvial features
	glacial geology
	glaciers
	rivers
	rivers and streams
	stream capture
	stream order
	streams
	geomorphology
	underground streams
	valleys
	watersheds
SN	Added to Thesaurus in 1993.

Triceratops
BT	Chordata
	.Vertebrata
	..Tetrapoda
	...Reptilia
	....Diapsida
	.....Archosauria
	......Ornithischia
	.......Ceratopsia
	........Ceratopsidae
	.........Triceratops
SN	Genus. Also search Agathaumas. This term has multiple hierarchies.

Trichinopoly India
USE	Tiruchirapalli India

trichloroethane
BT	organic compounds
	.halogenated hydrocarbons
	..chlorinated hydrocarbons
	...trichloroethane
RT	DDT
	ethane
SN	Sometimes a parent compound of DDT. Added to Thesaurus in 1989.

trichloroethene
USE	trichloroethylene

trichloroethylene
BT	organic compounds
	.halogenated hydrocarbons
	..chlorinated hydrocarbons
	...trichloroethylene
UF	trichloroethene
RT	ethylene
SN	Produced from heating tetrachloroethane with hydrated lime. Sometimes abbreviated TCE. Added to Thesaurus in 1989.

trichloromethane
USE	chloroform

Trichoptera
BT	Invertebrata
	.Arthropoda
	..Mandibulata
	...Insecta
	....Pterygota
	.....Neoptera
	......Endopterygota
	.......Trichoptera
SN	Order. Caddis flies.

triclinic
USE	triclinic system

triclinic system
BT	crystal systems
	.triclinic system
UF	triclinic
RT	crystallography
SN	Before 1985, also search triclinic. Added to Thesaurus in 1985.

Triconodonta
BT	Chordata
	.Vertebrata
	..Tetrapoda
	...Mammalia
	....Triconodonta
SN	Order.

Tridacna
BT	Invertebrata
	.Mollusca
	..Bivalvia
	...Tridacna
SN	Genus.

tridymite
BT	silicates
	.framework silicates
	..silica minerals
	...tridymite
RT	cristobalite
	opal-CT

Trieste Italy
BT	Europe
	.Southern Europe
	..Italy
	...Friuli-Venezia Giulia Italy
	....Trieste Italy
RT	Dinaric Alps
SN	City at head of the Adriatic Sea on Gulf of Trieste in SE Friuli-Venezia Giulia, NE Italy.

Trigg County Kentucky
BT	United States
	.Kentucky
	..Trigg County Kentucky

triggering
SN	Not a valid term for GeoRef. Use causes if applicable.

Trigonia
BT	Invertebrata
	.Mollusca
	..Bivalvia
	...Trigoniidae
	....Trigonia
SN	Genus.

Trigoniidae
BT	Invertebrata
	.Mollusca
	..Bivalvia
	...Trigoniidae
NT	Trigonia

trilate

trilateration
RT	cartography
	geodesy
	geodetic coordinates
	leveling
	triangulation
SN	Added to Thesaurus in 1985.

Trilobita
BT	Invertebrata
	.Arthropoda
	..Trilobitomorpha
	...Trilobita
NT	Agnostida
	Corynexochida
	Lichida
	Odontopleurida
	Phacopida
	Ptychopariida
	Redlichiida
RT	Crustacea
	Cruziana
	Rusophycus
	Trilobitoidea
SN	Class.

Trilobitoidea
BT	Invertebrata
	.Arthropoda
	..Trilobitomorpha
	...Trilobitoidea
RT	Trilobita
SN	Class.

Trilobitomorpha
BT	Invertebrata
	.Arthropoda
	..Trilobitomorpha
NT	Trilobita
	Trilobitoidea

Trilophosauria
BT	Chordata
	.Vertebrata
	..Tetrapoda
	...Reptilia
	....Diapsida
	.....Trilophosauria
RT	Araeoscelidia
SN	Includes the family Trilophosauridae. As of 1993, considered a narrower term of Archosauromorpha.

Trimble County Kentucky
BT	United States
	.Kentucky
	..Trimble County Kentucky

Trinidad
BT	Caribbean region
	.West Indies
	..Antilles
	...Lesser Antilles
	....Trinidad and Tobago
	.....Trinidad
RT	Carapita Formation
	Northern Range
SN	Island off NE coast of Venezuela in the Lesser Antilles. Major part of independent state of Trinidad and Tobago.

Trinidad and Tobago
BT	Caribbean region
	.West Indies
	..Antilles
	...Lesser Antilles
	....Trinidad and Tobago
NT	Tobago
	Trinidad
RT	Northern Range
SN	Comprises the islands of Trinidad and Tobago, Atlantic Ocean, off NE coast of Venezuela.

Trinity Complex
BT	United States
	.California
	..Trinity Complex
RT	Klamath Mountains
	Trinity County California
	Shasta County California
	Siskiyou County California
SN	Klamath 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
BT	United States
	.California
	..Trinity County California
RT	Eel River
	Trinity River
	Trinity Complex
SN	N California.

Trinity County Texas
BT	United States
	.Texas
	..Trinity County Texas
SN	E Texas.

Trinity Group
BT	Chronostratigraphic Units
	.Phanerozoic
	..Mesozoic
	...Cretaceous
	....Lower Cretaceous
	.....Trinity Group
BT	Chronostratigraphic Units
	.Phanerozoic
	..Mesozoic
	...Cretaceous
	....Comanchean
	.....Trinity Group
RT	Louisiana
	Oklahoma
	Texas
	Antlers Sands
	Arkansas
	Glen Rose Formation
	Paluxy Formation
	Pearsall Formation
	Rodessa Formation
	Travis Peak Formation
SN	Lower 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
RT	Humboldt County California
	Trinity County California
	California
	Texas
	Trinity River basin
SN	Flows 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
RT	Trinity River
	California
	Texas
SN	E Texas and NW California. Search in combination with appropriate state. Indexed with states as applicable. Added to Thesaurus in 1989.

triphylite
BT	phosphates
	.triphylite

triple junctions
RT	Chile Margin Triple Junction
	Mendocino fracture zone
	plate geometry
	Rodriguez triple junction
	plate tectonics

triplite
BT	halides
	.fluorides
	..triplite
BT	phosphates
	.triplite
SN	This term has multiple hierarchies.

tripoli
BT	sedimentary rocks
	.tripoli
RT	abrasives
	diatomite
	limestone
	chert
	diatomaceous earth
SN	Not 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
BT	Africa
	.North Africa
	..Libya
	...Tripoli Libya
SN	City on the Mediterranean Sea in NW Libya.

Tripolis Greece
BT	Europe
	.Southern Europe
	..Greece
	...Peloponnesus Greece
	....Tripolis Greece
RT	Gavrovo Zone
SN	City in central Peloponnesus, S Greece.

Tripolitania
BT	Africa
	.North Africa
	..Libya
	...Tripolitania
RT	Garian Libya
SN	NW 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
USE	diatomaceous earth

Tripp County South Dakota
BT	United States
	.South Dakota
	..Tripp County South Dakota

Tripura India
BT	Asia
	.Indian Peninsula
	..India
	...Northeastern India
	....Tripura India
RT	Bengal
SN	State E of Bangladesh in NE India.

Tristan da Cunha
BT	Atlantic Ocean Islands
	.Tristan da Cunha
NT	Gough Island
UF	Tristan da Cunha Islands
RT	Saint Helena
SN	A 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
USE	Tristan da Cunha

triterpanes
BT	organic compounds
	.hydrocarbons
	..triterpanes
NT	gammacerane
	hopanoids
	oleananes
RT	biomarkers
	diterpanes
	terpanes
SN	Added to Thesaurus in 1985.

triterpenoids
BT	organic compounds
	.isoprenoids
	..triterpenoids
RT	biomarkers
SN	Added to Thesaurus in 1995.

Triticites
BT	microfossils
	.Fusulinina
	..Fusulinidae
	...Triticites
NT	Triticites ventricosus
SN	Genus. This term has multiple hierarchies.

Triticites ventricosus
BT	microfossils
	.Fusulinina
	..Fusulinidae
	...Triticites
	....Triticites ventricosus
SN	This term has multiple hierarchies.

tritium
BT	isotopes
	.radioactive isotopes
	..tritium
BT	hydrogen
	.tritium
UF	H-3
RT	absolute age
SN	This term has multiple hierarchies.

Triton Satellite
RT	icy satellites
	Neptune
	Nereid Satellite
	satellites
	Voyager Program
SN	One of satellites of Neptune. Before 1989, also search Triton AND Neptune. Added to Thesaurus in 1989.

Trivandrum India
BT	Asia
	.Indian Peninsula
	..India
	...Kerala India
	....Trivandrum India
SN	Kerala, SW India.

TRM
USE	thermoremanent magnetization

Trochammina
BT	Invertebrata
	.Protista
	..Foraminifera
	...Textulariina
	....Lituolacea
	.....Trochammina
RT	microfossils
SN	Genus. Indexed with microfossils if applicable.

troctolite
BT	igneous rocks
	.plutonic rocks
	..gabbros
	...troctolite

Troia
USE	Troy

troilite
BT	sulfides
	.troilite
RT	meteorites
	pyrrhotite

Troja
USE	Troy

Troll Field
BT	Atlantic Ocean
	.North Atlantic
	..North Sea
	...Troll Field
RT	oil and gas fields
	giant fields
SN	Giant field, Horda Platform, 60 km offshore Norway, NE North Sea.

Trompia Valley
BT	Europe
	.Southern Europe
	..Italy
	...Lombardy Italy
	....Trompia Valley
SN	Valley of upper Mella River in E Lombardy, N Italy.

Troms Norway
BT	Europe
	.Western Europe
	..Scandinavia
	...Norway
	....Troms Norway
NT	Lyngen Peninsula
RT	Vesteralen
	Lapland
SN	County in far N Norway.

trona
BT	carbonates
	.trona
RT	sodium carbonate
	Searles Lake
SN	May be used as a commodity term with sodium carbonate.

Trona California
BT	United States
	.California
	..San Bernardino County California
	...Trona California
RT	Searles Lake
SN	Village in Mojave Desert of S California.

Trondelag
BT	Europe
	.Western Europe
	..Scandinavia
	...Norway
	....Trondelag
RT	Nord-Trondelag Norway
	Sor-Trondelag Norway
SN	Region in central part of country between Norwegian Sea and Swedish border around Trondheim Fjord. Indexed with counties as applicable.

Trondheim Norway
BT	Europe
	.Western Europe
	..Scandinavia
	...Norway
	....Sor-Trondelag Norway
	.....Trondheim Norway
SN	City on the Norwegian Sea.

trondhjemite
BT	igneous rocks
	.plutonic rocks
	..diorites
	...trondhjemite
RT	plagiogranite

Troodos Massif
BT	Asia
	.Middle East
	..Cyprus
	...Troodos Massif
UF	Troodos Mountain
	Troodos Mountains
RT	Agrokipia Deposit
	Troodos Ophiolite
SN	Mountainous mass SW of Nicosia which includes Mount Troodos, the highest peak on the island.

Troodos Mountain
USE	Troodos Massif

Troodos Mountains
USE	Troodos Massif

Troodos Ophiolite
RT	Agrokipia Deposit
	Cyprus
	Middle East
	Troodos Massif
SN	Added to Thesaurus in 1989.

trophic analysis
RT	biomass
	carnivorous taxa
	communities
	diet
	ecology
	ecosystems
	feeding
	nutrition
	paleoecology
	paleontology
	predation
SN	Added to Thesaurus in 1985.

tropical
SN	A valid term through 1977. After 1977, use tropical environment.

tropical environment
RT	climate
	depositional environment
	ecology
	equatorial region
	paleoclimatology
	rain forests
	subtropical environment
SN	Before 1978, search tropical.

troposphere
RT	atmosphere
	climate
	stratosphere
SN	Usually out-of-scope. Used with atmosphere.

Trotus Valley
BT	Europe
	.Moldavia
	..Trotus Valley
BT	Europe
	.Southern Europe
	..Romania
	...Trotus Valley
SN	River valley SSW of Bacau in W Moldavia. Also search Trotus; Trotus River. This term has multiple hierarchies.

Trou Sans Fond
BT	Atlantic Ocean
	.North Atlantic
	..Trou Sans Fond
UF	Le Trou Sans Fond
	Trou-Sans-Fond
RT	submarine canyons
	Ivory Coast
SN	Submarine canyon off SW Nigeria in the Bight of Benin.

Trou-Sans-Fond
USE	Trou Sans Fond

troughs
RT	aulacogens
	bottom features
	channels
	furrows
	gorges
	ocean floors
	trenches

Troup County Georgia
BT	United States
	.Georgia
	..Troup County Georgia

Trousdale County Tennessee
BT	United States
	.Tennessee
	..Trousdale County Tennessee
SN	N Tennessee.

Troy
BT	Asia
	.Middle East
	..Turkey
	...Troy
UF	Ilion
	Ilium
	Troia
	Troja
SN	Ancient ruined city. An archeological site, named Hissarlik, on the Menderes River S of the Dardanelles in NW Anatolia.

Trucial Coast
USE	United Arab Emirates
SN	A 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
USE	United Arab Emirates
SN	Former name of 7 British protected states on the Trucial Coast.

Truckee River
BT	United States
	.Truckee River
RT	California
	Nevada
SN	Rises 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
BT	South America
	.Venezuela
	..Trujillo Venezuela
RT	Lake Maracaibo
	Maracaibo Basin
SN	State in NW Venezuela.

Trumbull County Ohio
BT	United States
	.Ohio
	..Trumbull County Ohio
SN	NE Ohio.

Trust Territory of the Pacific Islands
SN	Not 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
BT	United States
	.New Mexico
	..Sierra County New Mexico
	...Truth or Consequences New Mexico
SN	Town in SW New Mexico.

Trypanites
BT	ichnofossils
	.Trypanites
SN	Genus.