aa axisa climate
aaaa channelaa lava
abandoned minesabatementabbe refractometer
ablationablation area/zoneablation cone
ablation meander coreablation moraineablation till
abney hand levelabnormal foldaboral
aborigineabraham’s treeabrasion
abrasive mineralsabrasive sandabrasive wheels
abrasivesabsarokiteabsolute
absolute ageabsolute humidityabsolute instability
absolute temperatureabsolute timeabsolute velocity
absolute zeroabsorptionabstraction
abutmentabysomed structureabyssal
abyssal floorabyssal hillabyssal plain
abyssal zoneacadian orogenyacasta gneiss
accelerationaccelerometeraccessibility isopleth
accessory mineralsaccident blockaccidental inclusions
accordantaccordion foldaccretion hypotheses
achondriteaciculate (adj)acid baths
acid igneous rockacid rain fallacid rock
acidicacmiteactinometer
active marginactive volcanoactonian
actual evapotranspirationadamantineadamellite
adaptationadaptive radiationadductor impressions
adhesionadiabaticadiabatic chart
adiabatic laps rateadiabatic processadit
adjacent seaadjacent streamsadsorption
adulariaadvanceadvastea
advection fogaegirineaeolian abrasion
aeolian placersaeolian processesaeolian sediment
aeolianiteaerial photographaero survey map
aerobeaerolitesaerological diagram
aerosolaetosauriaaf climate
after shockagateage group
age pyramidage specific death rateage structure
agentagents of weatheringagglomerate
aggradationaggregateagnatha
agonic linesagricultural densityagricultural limestone and lime
agricultureaiguilleair aloft
air currentsair gunair mass
air pollutionair pressureair temperature
aircraft industryalabasteralbedo
albian (adj)albite twinalbite-epidote-amphibolite facies
albitizationaleution lowalgae
algebraic sumalid scalealkali
alkali basaltalkali granitealkali igneous rocks
alkali lakesalkali peridotitealkali syneite
alkalinealkaline rockalkaline storage batteries
alkalinityallaniteallases
alligatorallimetric frequencyallochem
allochthonallochthonous (adj)allopatric speciation
allophaneallotriomorphicallotriomorphic texture
alloyalluvial diamondalluvial fan
alluvial placer depositsalluviumalpine orogeny
alternating axisaltiplanationaltitude
alto cumulusalto stratusalum
alum mineralsalumina refractoryalunite bleaching clay
am climateamberambulacrum
amethystammonoideaamoeboid fold
amorphousamositeamphi symmetry
amphibianamphibolesamphibolite
amphibolite faciesamplitudeamygdaloidal structure
amygduleanabatic (adj)anabatic wind
anaglyphanalcite basaltanalcitisation
analycite syeniteanalyseranalysis of igneous rocks
anamorphismanastomosing channelanatexis
anatomay of housesanchi-eutectic rocksancient formations
ancient mantle (or) wasteancient platformancient river
ancient topographyancient volcanoandesite
andesite lineanemographanemometer
aneroid barometerangle of depressionangle of elevation
angular momentumangular rock fragmentangular unconformity
angular velocityanhedral (euhedral)anhydrite
anionanisotropismannual moisture index
annual temperature ringannular drainage patternannular ring
anodeanomalyanorthosite
antarctic air massantarctic circleantecedent drainage
anthraciteanthropologyanthropometry
anti-conosiveantibioticantichlinal valley
anticlinal foldanticlineanticorrosion
anticycloneantimonial leadantipodes
antitradeapartheidapex
aphanitic (adj)aphelionaphorlith
apliteapogeeapparent dip
applied geographyaquamarineaqueduct
aquicludeaquiferaquifuge
aragonitearborealarborescant
arc of the meridianarchaeological maparchaic
archeanarcheologicalarctic air mass
arctic circlearctic frontarctic frontal zone
arctic kindredarctrench gaparcuate delta
areal extentareal grapharenaceons rock
areteargillaceousargillaceous rock
argillisationaridityaridity index
arithmatic densityarithmatic progressionarmouring
arroyoartefactsartesian
artesian basinsartesian conditionsartesian well
arthropodaartificial brinesartificial recharge
asas-planeasbestine
asbestosascending springaseismic plates
ash fall tuftash floodasperity
asphaltassimilationassortation of sediments
asteroidasthenosphereastrobleme
astrogeologyastronomical mapastronomy
astrophic balanceastrophysicsasymetric fold
atlasatmosphereatmospheric gases
atollatomic energyatomic reactor
atomic weldingatomsphereatomspheric pressure
attritionaugen structureaugite
augititeauredeauriferous deposits
auroraautomorphicauvulson
avalancheaverageaw climate
axial planeaxial plane facesaxial ratio
axisaxis of a foldaxis of symmetry
azimuthazimuthalazoic zone