ASBOG General Questions & Answers Updated 2026

ASBOG General
Questions &
Answers Updated
2026
WhatBisBaBfoldBlineBandBhowBisBitBused?B-
BAnswerTheBfoldBlineBisBaBhingeBlineBalongBwhichBaBverticalBcrossBsectionBmayBbeBco
nstructedBandBthenBflattenedBoutBtoBaBhorizontalBorBmapBview.BItBisBusedBtoBrepresen
tBtheBsubsurfaceBalongBanyBgivenBlineBinBaBmapBview.BItBneedBnotBbeBperpendicularBt
oBstrike.



WhatBisBtheBangleBandBsideBrelationshipsBforBtheBsinBequation?B-
BAnswersinαB=BoppositeBside/hypotenuse



WhatBisBtheBangleBandBsideBrelationshipsBforBtheBtangetBequation?B-
BAnswertanαB=BoppositeBside/adjacentBside



IfBanBattitudeBisBgivenBasB35,BS25E,BwhatBdoesBthatBmean?B-
BAnswerTheBattitudeB35,BS25E,BifBgivenBasBaBplane,BrepresentsBaBdipBofB35BinBtheBS2
5EBdirection.BThisBwouldBtranslateBtoBaBstrikeBofBN65EB(orB90Baway),BandBdipBofB35S.
BTheBBoardBwantsBtoBseeBanswersBinBtermsBofBstrikeBandBdipBwithBrespectBtoBtheBtw
oBnorthBquadrants.BTheBattitudeB35,BS25E,BifBgivenBasBanBapparentBdipBvaueBorBtheBb
earingBandBplungeBofBaBline,BrepresentsBaBlineBplungingB35BinBtheBdirectionBS25E.BAp
parentBdipBisBivenBinBtheseBtermsBtoBrepresentBtheBapparentBdipBangleBinBaBgivenBdir
ection.



WhatBisBtheBgeneralBformBofBtheBthicknessBequationBandBwhyBwouldn'tByouBwantBtoB
useBit?B-
BAnswerThicknessB(t)B=BoutcropBwidteBperpendicularBstrikeB(w)BsinB[dipB(δ),BslopeB(σ)].

,BGenerallyBitBisBeasierBtoBsolveBaBthicknessBproblemBgraphicallyBbecauseByouBneedBto
BdrawBaBdiagramBtoBscaleBanywayBtoBgetBtheBslopeBangleB(σ)BandBtheBperpendicularB
outcropBwidthB(w).



IfByouBhaveBaBflatBsurfaceBandBanBoutcropBwidthBthatBisBnotBperpendicularBtoBstrike,B
whatBequationBwouldByouBuseBtoBcalculateBtheBthicknessBofBtheBunit?B-
BAnswertB=BlBsinBβBsinBδ;BlB=BtraverseBdistanceBacrossBtheBoutcrop;BβB=BangleBbetwe
enBstrikeBandBapparentBdipBdirection;BδB=Bdip



WhatBisBtheBgeneralBequationBforBcalculatingBtheBapparentBdipBofBaBbedBandBwhenBc
an'tBthisBequationBbeBused?BWhatBotherBmethodsBcanBbeBusedBanBalternative?B-
BAnswertanαB=BtanδBsinβ;BαB=BapparentBdip;BδB=Bdip;BβB=B(angleBbetweenBstrikeBand
BapparentBdipBdirection);BThisBequationBcan'tBbeBusedBforBsolvingBtrueBstrikeBandBdipB
fromBtwoBapparentBdips.BInBorderBtoBsolveBaBproblemBinvolvingBtwoBapparentBdipsByo
uBmustBeitherBsolveBgraphicallyBorBusingBtheBstereonet.BTheBstereonetBsolutionBisBmuc
hBsimplerBandBlessBtimeBconsuming.



WhatBdefinesBanBIndexBFossil?B-
BAnswerAnBindexBfossilBidentifiesBandBdatesBtheBstrataBinBwhichBitBisBfound.BItBcombi
nesBaBwideBgeographicBrangeBwithBaBnarrowBstratigraphicBoccurrence.



WhatBisBnetBslipBandBwhereBisBitBmeasured?B-
BAnswerNetBslipBisBtheBdistanceBbetweenBtwoBformerlyBadjacentBpointsBonBeitherBside
BofBaBfault,BmeasuredBonBtheBfaultBsurfaceB(inBtheBplaneBofBtheBfault).



WhatBisBanBunconformity?B-
BAnswerAnBunconformityBisBaBgapBinBtheBgeologicBrecord;BanBinterruptionBinBtheBdep
ositionalBsequenceBthatBimpliesBupliftBandBerosionBhaveBremovedBpartBofBtheBgeologic
alBrecordBorBnon-depositionBhasBoccurred.



WhatBisBtheB"RuleBofBV's"?B-
BAnswerTheBoutcropBofBaBformationBasBitBcrossesBaBvalleyBformsBaBVBshapeB(asBview
edBonBaBmap).BTheBVBpointsBinBtheBdirectionBthatBtheBformationBunderliesBtheBvalley.

, WhatBisBaBtypeBlocality?B-
BAnswerABtypeBlocalityBisBtheBplaceBwhereBaBgeologicBfeatureB(suchBasBaBfossilBspecie
sBorBgeologicBformationBorBmember)BwasBfirstBrecognizedBandBdescribed.BItBcontainsBt
heBtypeBsection.



DefineBtypeBsection.B-
BAnswerTypeBsectionBisBtheBoriginallyBdescribedBstratigraphicBunitBtoBwhichBotherBpart
sBofBthBunitBinBotherBlocationsBmayBbeBcompared.BItBisBpreferableBtoBdescribeBtheBlo
cationBwhereBtheBunitBattainsBitsBmaximumBthicknessBandBwhereBthBtopBandBbottomB
ofBtheBunitBareBexposed.



HowBdoesBaBreverseBfaultBdifferBfromBaBnormalBfault?BHowBisBitBtheBsame?B-
BAnswerABnormalBfaultBisBaBdip-
slipBfaultBinBwhichBtheBhangingBwallBhasBmovedBdownBrelativeBtoBtheBfootBwall.BABre
verseBfaultBisBaBdip-
slipBfaultBinBwhichBtheBhangingBwallBhasBmovedBupBrelativeBtoBtheBfootBwall.BBothBn
ormalBandBreverseBfaultsBhaveBaBdipBbetweenB45BandB90.



WhatBisBtheBLawBofBInitialBHorizontality?B-
BAnswerTheBLawBofBInitialBHorizontalityBassumesBthatBtheBsequenceBofBlayersBwasBde
positedBhorizontallyBorBnearlyBso.BTheBoldestBlayerBisBthereforeBonBtheBbottomBandBth
eByoungestBlayerBisBonBtop.BInBdissectedBtopography,BtheByoungestBlayersBwillBformBhi
llBtops.



WhatBisBtheBLawBofBSuperposition?B-
BAnswerTheBLawBofBSuperpositionBstatesBthatBtheBoldestBlayerBisBonBtheBbottomBandB
theByoungestBlayerBisBonBtheBtop.BThisBassumesBthatBtheBlayersBhaveBnotBbeenBovert
urnedBduringBdeformation.BIfBtheBbedsBareBoverturnedBorBvertical,BtheBstratigraphicBsu
ccessionBcan'tBbeBdeterminedBunlessBtheBabsoluteBagesBofBtheBunitsBareBknown.BThisB
lawBappliesBtoBanyBlayeredBrockBsequenceBsuchBasBsedimentaryBunitsBorBextrusiveBign
eousBrocks.



HowBareBcross-cuttingBrelationshipsBusedBtoBdetermineBrelativeBages?B-
BAnswerIfBcross-
cuttingBrelationshipsBexist,BtheBfeatureBthatBisBcutBisBolderBthanBtheBfeatureBthatBcuts