Inrecentyears,infrastructureconstructiononcoralreefshasbeenincreasinglydeveloped.Therefore,theshallowstratastabilityofcoralreefsintheSouthChinaSeashouldbeevaluated.ThisstudyaimstoinvestigatetheprofilesfortheshallowstrataofcoralreefsinthesouthwestoftheYongshuReef,particularlyinthehydrodynamicmarineenvironment,andtoestablishageologicalmodelfornumericalsimulationusingGeo-Studio.Theshallowstrataofthecoralreefsincludemassgravel,sandgravel,mid-coarsesand,siltysand,finesand,andreeflimestone.Theshallowreefslopenearthelagoonissimilartoa‘layercake＇,inwhichthesideclosetotheseaisanalogoustoa‘blockcake＇.Thesimulationresultsshowedthatcoralreefstabilitydependsonwaveloadsandearthquakestrengthandonthephysicalpropertiesofcoralreefs.Thefactorofsafetyfortheouterreefisgreaterthan10.0understatic,wave,andseismicconditions;thisindicatedthattheouterreefswerelessaffectedbywavesandearthquakes.However,thefactorofsafetynexttothelagoonvariedfrom0.1to5.3.Thevariationwasprimarilycausedbythethickstrataofcoralreefsclosetothesea（reeflimestone,typicallywiththethickness〉10mandequivalenttoablock）.Thesoilandrocklayersinthecoralreefstratawiththicknesses〈10mshowedweakengineeringgeologicalcharacteristics.Ourfindingscanprovideusefulinformationtofutureconstructionprojectsoncoralreefs.
