Themechanismsofseismically-inducedliquefactionofgranularsoilsunderhighconfiningstressesarestillnotfullyunderstood.Evaluationofthesemechanismsisgenerallybasedonextrapolationofobservedbehavioratshallowdepths.ThreecentrifugemodeltestswereconductedatRPI'sexperimentalfacilitytoinvestigatetheeffectsofconfiningstressesonthedynamicresponseoradeephorizontaldepositofsaturatedsand.Liquefactionwasobservedathighconfiningstressesineachofthetests.Asystemidentificationprocedurewasusedtoestimatetheassociatedshearstrainandstresstimehistories.Thesehistoriesrevealedaresponsemarkedbyshearstrengthdegradationanddilativepatterns.Therecordedaccelerationsandporepressureswereemployedtogeneratevisualanimationsofthemodels.Thesevisualizationsrevealedaliquefactionfronttravelingdownwardandleadingtolargeshearstrainsandisolationofuppersoillayers.