Geologic map of the Bear Creek 7.5-minute quadrangle, Chatham and Moore Counties, North Carolina

NorthCarolinaDepartmentofEnvironmentalQuality ThisGeologicmapwasfundedinpartbytheUSGSNationalCooperativeGeologicMappingProgram NorthCarolinaGeologicalSurveyDivisionofEnergy,MineralandLandResources OpenFileReport2019-06 S.DanielSmith,DirectorKennethB.Taylor,StateGeologist INTRODUCTION TheBearCreek7.5-minuteQuadrangleliesintheeastcentral-portionoftheNorthCarolinaPiedmont.TheunincorporatedcommunitiesofBearCreekandHarpersCrossroads arepresentinthequadrangle.OldUSHWY421crossesthenortheastcorner,StateHWY902diagonalycutsacrossthenorthernportion,andStateHWY42cutsacrossthe southernportionofthequadrangle. BearCreekcontrolsthedrainageinthenorthernportionofthequadrangleanddrainsintotheRockyRiverwhichisamajortributaryoftheDeepRiver.Thesouthernportionofthe quadrangledrainsdirectlytotheDeepRiveralongnamedtributariesofTysonsCreek,IndianCreek,LitleIndianCreek,FalsCreekandotherunnamedtributaries.Natural exposuresofcrystalineandTriassicrocksprimarilyoccuralongthesenamedandunnamedcreeks.Rockexposureatroadcuts,ridges,resistantfinned-shapedoutcropsand pavementoutcropslocalyoccuroutsideofdrainages.Theelevationsinthemaparearangefromapproximately650feetabovesealevelonaresistanthil,neartheintersection ofSilerCity�GlendonRoadandProvidenceChurchRoad,inthenorthernportionofthequadrangle,toapproximately250feetalongseveraltributariesdrainingthesouthernedge ofthequadrangle. GEOLOGICBACKGROUND Pre-M esozoiccrystalinerocksintheBearCreekQuadranglearepartoftheredefinedHycoArc(Hibbardetal.,2013)withintheNeoproterozoictoCambrianCarolinaterrane(Hibbardetal.,2002;andHibbardetal.,2006).Intheregionofthemaparea,theCarolinaterranecanbeseparatedintotwolithotectonicunits:1)theHycoArcand2)theAaronFormationandtheassociatedvolcanicVirgilinamemberoftheredefinedVirgilinasequence(Hibbardetal.,2013).TheHycoArcconsistsoftheHycoFormationwhichincludeca.633to612M a(Wortmanetal.,2000;Bowman,2010;BradleyandM iler,2011)metamorphosedlayeredvolcaniclasticrocksandplutonicrocks.Availableagedates(Wortmanet al.,2000;BradleyandM iler,201)indicatetheHycoFormationmaytentativelybedividedintolower(ca.630M a)andupper(ca.615M a)portionswithanapparentinterveninghiatusofmagmatism.InnortheasternChathamCounty,HycoFormationunitsareintrudedbytheca.579M a(TadlockandLoewy,2006)EastFarringtonplutonandassociatedWestFarringtonpluton.TheAaronFormationconsistsofmetamorphosedlayeredvolcaniclasticrockswithyoungestdetritalzirconsofca.588and578M a(Polocketal.,2010 andSamsonetal.,2001,respectively).Hibbardetal.(2013)interpretsanatleast24milionyearunconformitybetweentheAaronandunderlyingHycoFormation. FOLDS TheHycoArcandAaronFormationlithologieswerefoldedandsubjectedtolowgrademetamorphismduringtheca.578to554M a(Polock,2007;Polocketal.,2010)Virgilinadeformation(GloverandSinha,1973;HarrisandGlover,1985;HarrisandGlover,1988;andHibbardandSamson,1995).Inthemaparea,originallayeringofHycoandAaronFormationlithologiesareobservedrangingfromshalowlytosteeplydippingandareinterpretedtobearesultofopentotightfoldsthatarelocalyoverturned. PreliminarystereogramanalysesofdatafromtwomapscalesynclinesinthenearbyColeridgeQuadrangle(Bradleyetal,2018),appearstoindicatethepresenceoffoldsrangingfromgentletoopen.SubsequentdomainanalysesofprimarybeddingandlayeringinHycoFormationandAaronFormationunitsoutsideofthetwosynclines,indicatefoldsrangefromtighttoopenwiththemajorityofthefoldswithinthetighttocloserange.Ingeneral,itappearsthattheHycoFormationandolderportionsoftheAaronFormationaremoretightlyfoldedcomparedtotheAaronFormationintheidentifiedsynclinesintheColeridgeQuadrangle.Thisapparentrangefromgentletotightfoldsisnotwelunderstoodand mayindicate:1)normaldisharmonicfoldingduetocompetencydifferencesbetweenunitsor2)indicatethattheyoungerunitswithinthesynclinesinColeridgearemore appropriatelyassignedtotheAlbemarleArclithologiesandweredepositedaboveanangularunconformity.M oreinvestigationisneeded. InsouthernportionoftheBearCreekQuadrangle,outcropscalefolds(bestexposedwithinthepyrophylitemines)deformanearlierfoliation.Thisfoldingisassociatedwithlocaldeformationalongseveralidentifiedhighanglereversefaultsinthemaparea(e.g.GlendonFault). FAULTS TheGlendonfault,locatedinthesouthernedgeofthequadrangle,haslongbeenrecognizedbypastworkers(e.g.Stuckey,1928andConley,1962).TheGlendonfaultisahigh anglereversefaultthatisalocusofpyrophylitealterationforadistanceofover30km(18miles)innortheastM ooreCountyandintosouthernChathamCounty.TheGlendonfaultisinterpretedtobeparaleltotheaxialsurfacesofregional-scaleoverturnedfoldsanddisruptsananticlinenearitscrest(Greenetal.,1982andKlein,1985).Ingeneral,theGlendonfaultisazoneofintensedeformationrangingfrom10to50meterswidewithabundantsmal-scalefolds,fracturesanddeformedandundeformedquartzveinsindicatingacomplicatedmovementhistory(Klein,1985).Quartzveinsmaybefoldedandhighstrainfoliationspresentwithinthefaultzoneoverprintand/ortransposeprimarybeddingand regionalfoliation. Severalotherhighanglereversefaultswithvaryingdegreesofhydrothermalalterationwereidentifiedduringmapping.M etamorphicfoliationdataindicatesthatthedipofthefoliationprogressivelybecomesmoreshalowtothesoutheastapproachingthehighanglefaults.Intheimmediateareaofthefaults,sericite(�phyrophylite)phylitesand schistosephyliteswithcomposite-likefabricsarecommon.Itisinterpretedthattheolderfoliationhasbeentransposedtoayoungerphyloniticfoliationwithinthefaultzone. Abundantevidenceofbritlefaultingattheoutcrop-scale,map-scaleandlarge-scalelineaments(asinterpretedfromhilshadeLiDARdata)arepresentinthemaparea.ThebritlefaultingandlineamentsareinterpretedtobeassociatedwithM esozoicextension.TheColoncross-structure(Reinemund,1955),locatedtotheeastofthestudyarea,isa constrictionzoneintheDeepRiverM esozoicbasinandischaracterizedbycrystalinerocksoverprintedbycomplexbritlefaulting. PASTWORK ThemapareaislocatedwithinthestudyareaofGreenetal.(1982),Abdelzahir(1978),andGreen(1977).Theirstudiesdocumentedthepresenceofanoverlappingseriesof metavolcanicandmetavolcaniclasticlithologiessourcedfromdistinctareas.Nixon(1954)mappedportionsoftheareaandinvestigatedthehistoriccopperprospectsandminesinthearea.M oore(1980)mappedandinvestigatedfelsicflowsthatincludedasmalportionofthesouthernedgeofthequadrangle. M INERALRESOURCES GLENDONPYROPHYLLITEDEPOSITS Thereisoneactivepyrophylitemineinthequadrangle.Pyrophyliteisusedtomanufactureavarietyofproductsfortherefractory,ceramicsandfilerindustries.TheactiveStandardM ineralsPyrophyliteM ineislocatedatthesouthernedgeofthequadrangleinM ooreCounty.TheareaaroundtheactivemineisknownastheGlendonpyrophylitedepositsandishometoseveralhistoriceconomicdepositsofpyrophylitethatwerefirstdocumentedintheearlytomid1800�s(Olmstead,1822andEmmons,1856).Stuckey(1928and1967)andConley(1962)conductedinvestigationsintothestructureandcharacteristicsofthedeposits.M cDaniel(1976)andSpence(1975)interpretedtheoriginofthepyrophylitedepositsasbeingrelatedtoancienthydrothermal(hotspring)activity.Klein(1985),aspartofadetailedfieldtripguide,describedaspectsofthegeology,mineralogyandstructureoftheGlendonpyrophylitedeposits. TheGlendonpyrophylitedepositsconsistoffourmines,fromsouthwesttonortheastinclude;Bates(inactive),Philips(inactive),Womble(activeStandardM ineralsmine)andWhite(inactiveforpyrophylite)M ines.TheinactiveBatesmineisinthequadrangleimmediatelytothesouth.SomeoftheearlyminingintheGlendonareawasunderground;miningispresentlyfromopenpits.TheminesarelocatedalongtheGlendonfault(Stuckey,1928andConley,1962). GOLD-PYROPHYLLITEBELTINM OORECOUNTY Lesure(1981)presentedtheresultsfromageochemicalreconnaissancestudyfromoldgoldmines,pyrophylitedepositsandroadoutcropsthroughoutnorthwesternM ooreCounty.Onehundredandninety(190)oftherocksamplescontainedgoldinquantitiesrangingfrom0.02to2.4ppm.Twenty-six(26)sampleswerecolectedfromtheGlendon pyrophylitedepositsandvicinitywithgoldvaluesrangedfrom0.02to0.04ppm. COPPERM INESANDPROSPECTS SeveralhistoriccopperdepositsarepresentinsouthwesternChathamCounty.IntheBearCreekQuadrangle,thecopperdepositsincludeseveralprospectsandsmalminesincluding;theBarringerPhilipsProspect,theBearCreekM ineandPhilipsM ine.M oredetaileddescriptionsofthedepositsareprovidedinBerry(1943),Nixon(1954)andCarpenter(1976).TheBarringerPhilipsProspectconsistedoftwopitsnowfiledin.TheBearCreekCopperM inewasworkedinthe1940�swithseveraltonsoforeremovedandhasanabandonedshaftupto32feetdeep.ThePhilipsM inewasalsoworkedinthe1940�swithseveralhundredtonsoforeremovedwithsubsequentexplorationandcolection ofrockcore;awaterfiledpitisalthatisleftoftheworkings.Coppermineralsreportedinclude:chalcopyrite,bornite,chalcocite,malachiteandazurite. TheHawBranchCopperDepositinM ooreCountywasbrieflydescribedbyConley(1962)andwasinvestigatedbyPowers(1985).Theprospectconsistsofseveralpits,shafts andatrench.Powers(1985)conductedgeologicmapping,fluidinclusionstudies,ageochemicaltraverseandelectricalresistivitytraverseofthedeposit.AdditionalworkintheHawBranchCopperdepositareawasconductedin1993(Powers,1993). DESCRIPTIONOFM APUNITS Alpre-M esozoicrocksinthemapareahavebeenmetamorphosedtoatleastthechloritezoneofthegreenschistmetamorphicfacies.M anyoftherocksdisplayaweakorstrongmetamorphicfoliation.Althoughsubjectedtometamorphism,therocksretainrelictigneous,pyroclastic,andsedimentarytexturesandstructuresthatalowfortheidentificationof protolithrocks.Assuch,theprefix�meta�isnotincludedinthenomenclatureofthepre-M esozoicrocksdescribedinthequadrangle.DikesofJurassicageddiabaseintrudethe crystalinerocksofthemaparea.Jurassicdiabasedikesarenotmetamorphosed.Quaternaryagedaluviumispresentinmostmajordrainages. M apunitsofmetavolcanicandmetavolcaniclasticrocksincludevariouslithologiesthatwhengroupedtogetherareinterpretedtoindicategeneralenvironmentsofdeposition.Thedaciticlavasandtuffsunitisinterpretedtorepresentdaciticdomesandproximalpyroclastics.Theandesitictobasalticlavas(withtuffsorconglomerates)unitsareinterpretedto representeruptionofintermediatetomaficlavaflowsandassociatedpyroclasticand/orepiclasticdeposits.Theepiclastic/pyroclasticunitsareinterpretedtorepresentdepositionfromtheerosionofdormantandactivevolcanichighlands.Someofthemetavolcaniclasticunitswithinthemapareadisplaylithologicrelationshipssimilartodatedunitspresentin northernOrangeandDurhamCounties.Duetothesesimilarities,themetavolcanicandmetavolcaniclasticunitshavebeententativelyseparatedintoupperandlowerportionsoftheHycoFormation;geochronologicdatainthemapareaisneededtoconfirmthisinterpretation.AreviewoftheregionallithologiesissummarizedinBradley(2013). ApreliminaryreviewoftheareageologyisprovidedinBradley(2013).UnitdescriptionscommontoBradleyetal.(2017)andHannaetal.(2015)fromtheSilerCityandSilerCityNEgeologicmaps,respectivelywereusedforconformitywithonstrikeunitsinneighboringquadrangles.Unitdescriptionsandstratigraphiccorrelationsweremaintainedfrom adjacentmappinginOrangeCounty(Bradleyetal.,2016).ThenomenclatureoftheInternationalUnionofGeologicalSciencessubcommissiononigneousandvolcanicrocks(IUGS)afterLeM aitre(2002)isusedinclassificationandnamingoftheunits.Theclassificationandnamingoftherocksisbasedonrelictigneoustextures,modalmineral assemblages,ornormalizedmineralassemblageswhenwhole-rockgeochemicaldataisavailable.PyroclasticrockterminologyfolowsthatofFisherandSchminke(1984). Neoproterozoic Mesozoic Quaternary CORRELATION Qal aluvium OFMAPUNITS Qt terracegraveldeposits Jd diabase TriassicSedimentaryRocks DeepRiverBasin:SanfordSub-basin Trc Trp AlbemarleArcPluton(?) Zdi AaronFormaYoungestdetritaltionzirconsfca.588and578a o M(Polocketal.,2010andSamsonetal.,2001,respectively) Za Zam(Zhe*?) Zae/pl Zaqdp HycoFormation-upperportion Metamorphosedvolcaniclasticsedimentaryandpyroclastic rocksassociatedwithHycoFormation:upperportion ca.616-612M a(Wortman,etal.,2000;Bowman,2010;andBradleyandM iler,2011) Zhe* Zhime/pl Zhable Zhe/pl Zhdlt(u) Stratigraphicrelationsuncertain 7930' A 7922'30" 3537'30" 85 81 66 3537'30" Zhime/pl 65 82Zdi 86 60 40 48 Za 75 81 87 80 4486 80 85 54 81 79 81 Zhe* 80 78 89 84 38 66 79 86 80 51UD 86 Zhe* 81 Qal Za 56 57 8288 56 78 61 7482 88 81 Za 88 69 58 76 74 78 88 74 50 76 52 70 78 81 73 88 52Zhime/pl 88 81 79 79 18 50 8987 70 84 86 76 64 8144 59Qal 81 71 87 Qal Zhe* Qal 86 68 Za 87 60 89 86 Qal 84 79 8087 85 59 81 87 8186 8887 87 74 70 76 55 44 Qal Zhdlt(u) 8184 Qal 68 89 85 66 88 8886 79 88 68 71 68 74 74 70 84 84 84 79 72 7884 84 79 88 76 81 62 72 60 74 7556 60 77 80 76 80 88 89 88 72 49 74 Za 81 79 77 7662 Za84 70 65 Qal 82 84 89 76 Qal84 70 76 34 73 59 60 86 68 88 7988 84 59 82 66 74 83 77 89 69 Zhime/pl 74 7484 56 5581 81 85 8981 88 Za 83 76 72 84 86 71 69 84 88 85 78 77 6576 88 Qal 72 85 84 75 88 75 84 66 78 88 65 84 8585 84 79 89 74 8274 7688 72 87 86Zae/pl 73 89 68 60 75 88 6851 78 75 78 69 66 79 88 81 84 81 89 88 25 45 87 76 72 57 72 64 Zhime/pl 46 42 84 62 49Qal88 87 42 88 84 78 7582 88 82 80 63 85 82 73 80 65 75 85 79 81 85 5972 82 81 70 82 82 71 71 Qal 76 80 72 82 76 23 66 44 66 81 75 80 76 68 87 27 84 87 79 88 82 56 U 52 D54 12 84 76 82 72 84 Zhable 82 81 87 Qal 76 70 68 7774 59 81 72 Zhable64 77 77 81 88 71 8886 72 82 Qal 66 62 64 81 80 76 50 49 50 75 80 88 48 78 Zhime/pl U D 88 88 76 69 89 55 7882 87 79 28 84 62 D 8276 Zae/pl 49 42 81 75 60 U 82 67 35 5185 88 8047 7571 86 88 84 78 80 62 6484 80 Za 76 62 88 5670 70 80 74 89 81 78 84 76 1 Zaqdp Za 86 76 Qal 76 82 Za 52 69 8285 84 84 4974 49 77 70 76 49 D70 36 78 75 61 73 74 88 74U 86 33 46 71Qal 48 66 85 83 7976 30 54 82 66 61 59 51 D 67 84 68 52 80 79 84 68 71 U 77 86 5562 85 76 84 76 e 59 29 47 Zhabl 69 Qal 80 61 81 Zhime/pl 65 70 87 40 81 77 36 88 78 88 83 76 4 81 86 82 80 7151 8275 77 88 Zhable81 69 Zhable46 85 Zae/pl 80 6572 7969 58 2686 84 81 Zhime/pl 79 D55 75 66 82 73 18 48 U 61 49 Trp 38 50 Qal DU 319 78 86 78 Za 24 53 6083 64 86 87 78 79 20Za 47 78 Qal63 88 86 54 26 19 14 37 Zae/pl 62 60 80 64 62 80 57 82 Zhime/pl 61 85 26 82 81 52 30 81 44 62 87 2478 19 85 84 88 88 33 75 68 66 85 83 40 56 28 70 87 74 73 87 68 47 23 28 6268 59 78 37 2266 5080 Zhime/pl 66 82 50 86 85 41 61 36 Qal 1673 14 41 61 Qal 23 26 62 Qal28 54 8981 78 84 76 80 88 35 74 1486 86 Za 42 86 69 Qal 82 84 19 69 11 3088 38 81 35 55 69 43 86 82 Qal 71 38 15 Qal 79 35 85 8188 61 74 Zhime/pl 86 2576 87 87 88 82 62 4576 86 54 57 Zam(Zhe*?)83 83 Zhable 65 65 70 53 35 78 39 77 68 74 74 74 62 Zhdlt(u)84 Qal 55 85 11 14 66 5482 75 6869 86 88 10 2570 2 Za 65 8187 46 84 72 56 46 78 72 57 80 Zam(Zhe*?) 55 68 61 70 75 46 74 80 5 77 U D Zhable 67 42 6 88 66 83 Qal 77 Zhable 75 79 43 44 68 79 60 Za 81 86 51 8446 84 68 68 13 66 85 86 5 Zhime/pl 36 24 51 24 74 42 47 82 85 84 86 Zam(Zhe*?) Zhable 51 88 48 8620 68 30 18 55 8165Zhime/pl 78 34 41 12 78 73Zhable 55 87 31 88 86 13 61 28 2048 53 62 81 46 U 55 69 Za D 78 80 80 86 Zhable Zhime/pl 26 21 49 81 D 57 Zhdlt(u) Zhdlt(u) U U 7676 84 71 Qal Za D 38 60 43 75 81 88 88 66 Zhable 87 68 71 65 75 78 75 57 56 Zhable 78 75 87 84 75 82 75 75 74 57 47 85 e 74 52 Zhable 7174 44 74 87 55 61 77 Zhabl56 72 73 8 34 59 78 76 56 Zhable 86 7 82 76 72 46 68 67 37 70 83 26 5917 Zhime/pl72 82 38 68 60 46 50 74 54 41 80 50 35 35 64 77 71 4911 65 53 49 86 85 Zhable 39 36 74 80 68 76 81 75 66 60 66 7750 66 8570 45 72 40 85 50 54 8271 68 Zhable 60 29 Zhable 22 57 Trp64 82 64 68 62 Zhe/pl 64 83 60 44 15 49 29 84 84 79 74 68 85 88 84 54 64 39 Zhime/pl 76 3570 42 52 39 52 76 76 65 84 8484 48 87 34 Zhdlt(u) 88 39 8454 4065 65 62 40 31 78 75 86 66 26 54 74 78 84 42 80 Qal 9 Zhable 32 14 78 1864 64 78 77 74 88 76 5242 18 Zhe/pl 84 Qal 83 7479 8479 53 87 37 71 28 43 77 6064 28 1024 Zhable 75 Zhable 64 82 31 22 59 85 35 22 41 75 Zhe/pl 37 48 40 38 7820 56 U32 74 38 84 74 35 40 78 70 D 86 Qt39 Zhdlt(u) 39 64 78 42 71 81 87 40 88 52 43 34 40 73 8246 75 1 16 10 81 Trp 8 78 59 31 85 Qal 81 45 85 41 738 68 20 49 76 54 Zhable 65 3530' 55 53 6851 76 79 84 74 42 87 47 75 30 Zhime/pl Zam(Zhe*?) 21 82 31 Trc A' 21 3530'30" 7930' 7922'30" SedimentaryUnits Qal�Alluvium:Unconsolidatedpoorlysortedandstratifieddepositsofangulartosubroundedclay,silt,sandandgravel-toboulder-sizedclasts,instreamQal drainages.Mayincludepointbars,terracesandnaturalleveesalonglargerstreamfloodplains.StructuralmeasurementsdepictedonthemapwithinQalrepresent outcropsofcrystalinerockinlierssurroundedbyaluvium. Qt�Teracedeposits:Unconsolidatedclay,silt,sand,gravel,andcobblesabovecurrentfloodplainlevel;gravel-andcobble-sizedmaterialaretypicalycomposedQt ofsubroundedtosubangularquartzclasts.Reinemund(1955)identifiesfourterracedepositsintheDeepRiverareadistinguishedontheiroccurrenceatspecific elevations. Trp�PekinFormation:Gray,browntomaroon,whitemicabearing,interbeddedmudstones,siltstonesandarkosicsandstones.OutcropsandbouldersoffloatTrp identifiedaspartofPekinFormationarestronglyinduratedcomparedtoconglomeratesidentifiedaspartofChathamGroup.IdentifiedasthePekinFormationbyReinemund(1955). Trc�CumnockFormation:Grayandblackclaystone,shaleandsiltstone.Graysandstoneandconglomerate.Containsbedsofcoalandcarbonaceousshale(Reinemund,1955).ExposuresoftheCumnockFormationwerenotencounteredduringfieldmapping.AreaofCumnockincludedonmaptoedgematchwithhistoricdata. IntrusiveandM etaintrusiveUnits Jd�Diabase:Blacktogreenish-black,fine-tomedium-grained,dense,consistsprimarilyofplagioclase,augiteandmaycontainolivine.Localyhasgabbroictexture.Occursasdikesupto100ftwide.Diabasetypicalyoccursasspheriodalyweatheredboulderswithagrayish-brownweatheringrind.Redstationlocationindicatesoutcroporbouldersofdiabase.Purplestationlocationsindicateoutcroporbouldersofgabbroictextureddiabase. Zdi�Diorite:M esocratic(CI~50),greenish-graytograyish-green,fine-tomedium-grained,metamorphosed,hypidiomorphicgranulardiorite.M ajormineralsincludeZdi plagioclaseandamphibole.Plagioclasecrystalsaretypicalysericitizedandsaussuritized.Amphibolesaretypicalyalteredtochloriteandactinolitemasses.Gabbrointermingledlocaly. M etavolcanicandM etavolcaniclasticUnits AaronFormation Zae/pl�AaronFormation(Virgilinamember)mixedepiclastics,pyroclasticsandlavasoftheDevilsTrampingGroundarea:Grayish-greentogreenish-gray, Zae/pl metamorphosedtuffaceoussandstones,conglomeraticsandstones,siltstonesandminorphylite.Thesiltstonestypicalyareweaklyphylitic.Containslesser amountsoffine-tocoarsetuff,weldedtuffanddaciticlavas.Fiamme-likeshapedclastsarecommonintheconglomerates,sandstonesandtuffs.Quartzandfeldsparcrystalfragmentsarecommoninthesedimentarycomponents,tuffsandlavas.Silicifiedand/orsericitizedalteredrockandquartzwithadulariaarelocalypresent.UnitisinterpretedtobeingradationalcontactwithunitZa.ContactwithunitZadesignatedatfirstoccurrenceofsandstoneswithangularclastsorprimaryvolcanicrocks. Zaqdp-Quartzdaciteporphyry:Porphyriticwithaphaniticgroundmassandsub-toeuhedralphenocrysts(2-6mm)ofwhitetosalmonplagioclaseandgraytodarkZaqdp gray(beta-)quartz;phenocryststypicalyconstitute20to25%oftherock.M aylocalyhavefine-grainedintrusivetexture.Interpretedaseitherlavaflowsorshalow intrusivespossiblyassociatedwithdomes.SimilartoquartzdaciteporphyryunitwithintheBynumQuadrangle(Bradleyetal.,2013). Za�AaronFormation:Distinctivemetasedimentarypackagethatrangesfromfine-grainedsiltstonestocoarse-grainedsandstones,pebblysandstonesand Za conglomerates.SiltstonesaresimilarinappearancetoHycoFormationlithologies.Thesandstones,pebblysandstonesandconglomerates(classifiedaslitharenite,feldspathiclithareniteandlithicfeldsarenitebyHarris(1984)aredistinctiveandcommonlycontainroundedtosubroundedclastsofquartzrangingfrom sand-togravel-sized.Inthesandstones,feldsparisthemostprominentmineralgrain;quartzvariesfromsparsetoabundantinhandsample.Lithicclastsaretypicalyprominentandrangefromsand-togravel-size.Harris(1984),performedadetailedsedimentarystudyoftheAaronFormationtotheimmediatewestofthe maparea.Harris(1984)interpretedtheAaronFormationtohavebeendepositedbyturbiditycurrentsinaretrogradationalsubmarinefanseting. Zam(Zhe*?)�AaronFormationmudstones(possibleHycoFormationmudstones):Distinctivethinlybeddedtoverythinlybeddedsiltstonesandmudstones.AaronFormationmudstonesaredistinguishedfromHycoFormationmudstonesbythepresenceofinterlayeredquartzbearingsandstonesintheAaron.Withoutthe presenceofthedistinguishingquartzbearinginterlayers,thisunitistentativelyassignedtotheAaronFormation. HycoFormation�UpperPortion Zhe*-EpiclasticrocksoftheSouthernChathamCountyarea:Grayish-greentogreen,localywithdistinctivereddish-grayormaroontolavendercoloration, Zhe* siltstones,sandstones,conglomeraticsandstone,andconglomeraticsiltstone(greywacke).Siltstonesarelocalyphylitic.Siltstonestypicalydisplaybeddingrangingfrommm-scaleupto10cm,beddinglayerstraceableforseveralfeetlocaly,mayexhibitsoftsedimentdeformation.Localytuffaceouswitharelictvitrictexture.Localycontaininterbeddedintermediatetomaficlavas.Conglomeratesandconglomeraticsandstonestypicalycontainroundedtoangularclasts.Depositioninterpretedasdistalfromvolcaniccenter. Zhime/pl-Mixedintermediatetomaficepiclastic-pyroclasticrockswithinterlayeredintermediatetomaficlavas:Grayish-greentogreen,localywith Zhime/pl distinctivereddish-grayormaroontolavendercoloration;metamorphosed:conglomerate,conglomeraticsandstone,sandstone,siltstoneandmudstone.Lithologies arelocalybedded;localytuffaceouswithacryptocrystaline-likegroundmass.Siltstonesarelocalyphylitic.LocalycontaininterbeddedintermediatetomaficlavasidenticaltotheZhableunit.Containslesseramountsoffine-tocoarsetuffandlapilituffwithacryptocrystaline-likegroundmass.Pyroclastics,lavas,andepiclastics aremainlyintermediatetomaficincomposition.M inordaciticlavasandtuffspresent.Silicifiedand/orsericitizedalteredrockarelocalypresent.Conglomeratesand conglomeraticsandstonestypicalycontainsubroundedtoangularclastsofandesiteandbasaltinaclasticmatrix.Generalyinterpretedtohavebeendeposited proximaltoactiveintermediatetomaficcompositionvolcaniccentersand/orrecordtheerosionofproximalintermediatetomaficcompositionvolcaniccentersafter cessationofactivevolcanism. Zhdlt(u)�DaciticlavasandtuffsoftheupperportionoftheHycoFormation:Greenish-graytodarkgray,siliceous,metamorphosed:aphaniticdacite, Zhdlt(u) porphyriticdacitewithplagioclasephenocrysts,andflowbandeddacite.Dacitewithhyaloclastictexturesarecommon.Weldedandnon-weldedtuffsassociatedwiththelavasinclude:greenish-graytograyish-green,finetuff,coarseplagioclasecrystaltuffandlapilituff.Localy,interlayersofimmatureconglomerateand conglomeraticsandstonewithabundantdaciteclastsarepresent.Thedacitesareinterpretedtohavebeencoherentextrusivesorveryshalowintrusionsassociated withdomeformation.Thetuffsareinterpretedasepisodicpyroclasticflowdeposits,airfaltuffsorreworkedtuffsgeneratedduringformationofdacitedomes.Wortmanetal.(2000)reportsanageof615.7+3.7/-1.9M aU-PbzircondateforadacitictufffromtheunitintheRougemontquadrangle. Zhable�Andesitictobasalticlavaswithinterlayeredepiclasticrocks:Lightgreen,gray-green,gray,anddarkgray;typicalyunfoliated,amygdaloidal, Zhable plagioclaseporphyritic,amphibole/pyroxeneporphyriticandaphanitic;metamorphosed:andesitictobasalticlavasandshalowintrusions.Hyaloclastictextureis commonandimpartsafragmentaltextureonsomeoutcropsandfloatboulders.Containslesseramountsofgrayish-green,lightgreen,andlightgraytowhite;metamorphosedconglomerate,conglomeraticsandstone,sandstone,siltstoneandmudstone. Zhe/pl-Mixedepiclastic-pyroclasticrockswithinterlayereddaciticlavas:Grayish-greentogreenish-gray,localywithdistinctivereddish-grayormaroontolavendercoloration;metamorphosed:conglomerate,conglomeraticsandstone,sandstone,siltstoneandmudstone.Lithologiesarelocalybedded;localytuffaceous withacryptocrystaline-likegroundmass.Siltstonesarelocalyphylitic.LocalycontaininterbeddeddaciticlavasidenticaltoZhdltunit(notpresentinquadrangle).Containslesseramountsoffine-tocoarsetuffandlapilituffwithacryptocrystaline-likegroundmass.Pyroclastics,lavas,andepiclasticsaremainlyfelsicin composition.M inorandesitictobasalticlavasandtuffspresent.Silicifiedand/orsericitizedalteredrockarelocalypresent.Conglomeratesandconglomeratic sandstonestypicalycontainsubroundedtoangularclastsofdaciteinaclasticmatrix.PortionsoftheZhe/plunitareinterpretedtohavebeendepositedproximalto activevolcaniccentersrepresentedbytheZhdltunitbutarealsointerpretedtorecordtheerosionofproximalvolcaniccentersaftercessationofactivevolcanism. Trc Jd EXPLANATIONOFMAPSYMBOLS CONTACTS,FAULTS,ANDOTHERFEATURES INCROSSSECTION PLANARANDLINEARFEATURES PROSPECTSANDQUARRIES OTHERFEATURES PlotsandcalculationscreatedusingStereonetv.10.2.0basedonAlmendingeretal.(2013)andCardozoandAlmendinger(2013). EqualAreaSchmidtNetProjectionof EqualAreaSchmidtNetProjectionof UnidirectionalRoseDiagramofJointsN=488 ContouredPolestoPrimaryBedding,Layering ContouredPolestoFoliationandCleavage OuterCircle=10% andWelding/CompactionFoliation ContourInterval=2sigma;N=494 Meanvector=127��43�;ContourInterval=2sigma;N=124 TRAVERSEMAP Hilshadederivedfroma20footLiDARdigitalelevation model.Redandbluelinesshowpathsoffieldtraverses. GeologicdatacolectedinJune2017throughM ay2018andJune2018throughM ay2019. Acknowledgments:UnpublisheddataprovidedbyJohnPowers(Powers,1993)was bycarutilizedtohelpdrawgeologiccontactsinthesoutheastportionofthemaparea. byfoot inferredcontact reversefault-inferred; ? interpretedfoldhingeofanticline;queriedwherequestionable dotedwhereconcealed concealedcontact interpretedfoldhingeofsyncline;quaternaryaluviumcontact ? dotedwhereconcealed gradationalcontact-inferred;dotedwhereconcealed lineargeomorphicfeature interpretedfoldhingeofoverturnedanticline interpretedfromhilshadeLiDAR-originuncertain inferredbritlefault; interpretedfoldhingeofoverturnedsyncline;U dotedwhereconcealed ? queriedwherequestionableDindicatesdownthrownside, inferreddiabasedike;D Uindicatesupthrownside dotedwhereconcealed A A' crosssection britlefaultinferredcontact (arrowsindicatedirectionofmotion) inferredgradationalcontact inferredfoldaxis 74 strikeanddipofprimarybeddingand/orlayering 77 strikeanddipofcleavage 78 strikeanddipofinclinedjointsurface 82 (multipleobservationsatonelocation) 60 strikeanddipofprimarybeddingand/orlayering70 (multipleobservationsatonelocation) strikeanddipofcleavage75 84 (multipleobservationsatonelocation) strikeofverticaljointsurface (multipleobservationsatonelocation)strikeanddipofprimaryvolcanic 78 compactionand/orweldingfoliation 71 strikeanddipofinclinedjointsurface 65 strikeanddipofquartzvein 69 strikeanddipofinclinedregionalfoliation 56 strikeanddipofslickenside 81 strikeanddipofinclinedregionalfoliation 19 (multipleobservationsatonelocation) clastlineation 84 (multipleobservationsatonelocation) 63 trendandplungeof 56 strikeanddipof 19 strikeanddipofaxialsurface crenulationlineationshearfoliation (multipleobservationsatonelocation) 1464 strikeanddipofshearfoliation trendandplunge(multipleobservationsatonelocation) strikeofverticaljointsurface orslickenline prospect(pitorsmalopencut) quarryormine-active1RoadsProspect�copper(USGS,MRDS);NotconfirmedbyNCGS 10StandardMinerals(Womble)PyrophyliteMine-pyrophylite4prospect�unknowncommodity(identifiedbyNixon,1954);Not confirmedbyNCGS quarryormine-abandoned5BarringerPhilipsProspect�copper(USGS,MRDS;Carpenter,1976) 3PhilipsMine�copper(USGS,MRDS;Carpenter,1976;Nixon,1954) 6OldhamPyrophylitePit�pyrophylite(Reinemund,1955);approximate location 9White(Snow)PyrophyliteMine-pyrophylite(Reinemund,1955) 7JonesPyrophylitePit-pyrophylite(Reinemund,1955);approximate 1PhilipsPyrophyliteMine-pyrophylite locationfromPowers(1993) 16unnamedquarry/pit�flagstone 8CurriePyrophylitePit-pyrophylite(Reinemund,1955);approximatelocation borrowpit-abandoned14HawBranchCopperDeposit�copper(Powers,1985);multiplepoints 17unnamedborrowpit�filmaterial18prospectpit�copper19prospectpit�copper20prospectpit�pyrophylite mineshaft-abandoned21prospectpit�pyrophylite 2BearCreekMine�copper(USGS,MRDS;Carpenter,1976;Nixon,1954)22prospectpit�pyrophylite 15prospect�abandonedshaft�copper(Powers,personalcommunication) observationstationlocation diabasestationlocation indicateslocationofquartzdacite indicateslocationofgabbroic porphyrybouldersoroutcrop diabasebouldersoroutcrop Geochemicalsamplelocationindicateslocationofvuggyand/or 12NdisotopeanalysisHOC92-7(Samsonetal.,1995)massivequartzfloat 13NdisotopeanalysisHOC92-8(Samsonetal.,1995) REFERENCES: Abdelzahir,A.M.,1978,ThegeologyoftheCarolinaslatebelt,northernM ooreCounty,NorthCarolina,unpublishedM .S.thesis,NorthCarolinaStateUniversity,Raleigh,NorthCarolina,67p.Allmendinger,R.W.,Cardozo,N.C.,andFisher,D.,2013,StructuralGeologyAlgorithms:VectorsandTensors:Cambridge,England,CambridgeUniversityPress,289pp.Bery,E.W.,1943,ThecopperprospectsofChathamCounty:NorthCarolinaDepartmentofConservationandDevelopment,DivisionofM ineralResources,ReportofInvestigation�TheCopperProspectsofChathamCounty,R.I.43,8p.Bowman,J.D.,2010,TheAaronFormation:EvidenceforaNewLithotectonicUnitinCarolinia,NorthCentralNorthCarolina,unpublishedM .S.thesis,NorthCarolinaStateUniversity,Raleigh,NorthCarolina,16p.Bradley,P.J.,andMiller,B.V.,201,NewgeologicmappingandageconstraintsintheHycoArcoftheCarolinaterraneinOrangeCounty,NorthCarolina:GeologicalSocietyofAmericaAbstractswithPrograms,Vol.43,No.2.Bradley,P.J.,2013,TheCarolinaterraneonthewestflankoftheDeepRiverBasininthenorthernPiedmontofNorthCarolina�AStatusReport,inHibbard,J.P.andPolock,J.C.editors,2013,Onearc,twoarcs,oldarc,newarc:TheCarolinaterraneincentralNorthCarolina,CarolinaGeologicalSocietyfieldtripguidebook,pp.139-151.Bradley,P.J.,Hanna,H.D.,Gay,N.K.,Stoddard,E.F.,Bechtel,R.,Phillips,C.M.,andFuemmeler,S.J,2016,GeologicmapofOrangeCounty,NorthCarolina:NorthCarolinaGeologicalSurveyOpen-fileReport2016-05,scale1:50,000,incolor.Bradley,P.J.,Peach,B.T.andHanna,H.D2017,GeologicmapoftheSilerCity7.5-M inuteQuadrangle,ChathamCounty,NorthCarolina:NorthCarolinaGeologicalSurveyOpen-fileReport2017-07,scale1:24,000,incolor(SupersedesOpen-fileReport2016-08).Bradley,P.J,Peach,B.T.andHanna,H.D.,2018,GeologicmapoftheChathamCountyportionoftheColeridge7.5-minuteQuadrangle,ChathamandRandolphCounties,NorthCarolina:NorthCarolinaGeologicalSurveyOpen-fileReport2018-03,scale1:24,000,incolor.(SupersedesOpen-fileReport2016-1).Cardozo,N.,andAllmendinger,R.W.,2013,SphericalprojectionswithOSXStereonet:ComputersandGeosciences,v.51,no.0,p.193-205,doi:10.1016/j.cageo.2012.07.021Carpenter,P.AlbertI.,1976(reprinted1993),M etalicmineraldepositsoftheCarolinaSlate,NorthCarolinaGeologicalSurvey,Bu letin84,89p.Conley,J.F.,1962,GeologyandmineralresourcesofM ooreCounty,NorthCarolina:DivisionofM ineralResources,NorthCarolinaDepartmentofConservationandDevelopment,Bu letin76,40p.Emmons,E.,1856,GeologicalReportoftheM idlandCountiesofNorthCarolina:NorthCarolinaGeologicalSurvey,M iscelaneousPublication.Fisher,R.V.,andSchminckeH.-U.,1984,Pyroclasticrocks,Berlin,WestGermany,Springer-Verlag,472p.Glover,L.,andSinha,A.,1973,TheVirgilinadeformation,alatePrecambriantoEarlyCambrian(?)orogeniceventinthecentralPiedmontofVirginiaandNorthCarolina,AmericanJournalofScience,Cooperv.273-A,pp.234-251.Green,G.,1977,ThegeologyoftheslatebeltrocksoftheGoldstonandBearCreekquadrangles,NorthCarolina,un-publishedM .S.thesis,NorthCarolinaStateUniversity,Raleigh,NorthCarolina,68p.Green,G.,Cavaroc,V.,Stoddard,E.,Abdelzahir,A.,1982,VolcanicandvolcaniclasticfaciesinapartoftheslatebeltofNorthCarolina,In:Bearce,D.,Black,W.,Kish,S.,Tu l,J.(Eds.),TectonicstudiesintheTaladegaandCarolinaslatebelts,SouthernAppalachianOrogen.GeologicalSocietyofAmericaSpecialPaper,vol.191,pp.109�124.Hanna,H.D.,Bradley,P.J.,andBechtel,R.,2015,GeologicM apoftheSilerCityNE7.5M inuteQuadrangle,ChathamCounty,NorthCarolina:NorthCarolinaGeologicalSurveyOpen-fileReport2015-02,scale1:24,000,incolor.Ha ris,C.W.,1984,Coarse-grainedsubmarine-fandepositsofmagmaticarcaffinityinthelatePrecambrianAaronFormation,NorthCarolina,U.S.A.,PrecambrianResearch,26,pp.285-306.Ha ris,C.,andGlover,L.,1985,TheVirgilinadeformation:implicationsofstratigraphiccorrelationintheCarolinaslatebelt,CarolinaGeologicalSocietyfieldtripguidebook,36p.Ha ris,C.,andGlover,1988,Theregionalextentoftheca.600M aVirgilinadeformation:implicationsofstratigraphiccorrelationintheCarolinaterrane,GeologicalSocietyofAmericaBu letin,v.100,pp.200-217.Hibbard,J.,andSamson,S.,1995,OrogenesisexotictotheIapetancycleinthesouthernAppalachians,In,Hibbard,J.,vanStaal,C.,Cawood,P.editors,CurrentPerspectivesintheAppalachian�CaledonianOrogen.GeologicalAssociationofCanadaSpecialPaper,v.41,pp.191�205.Hibbard,J.,Stoddard,E.F.,Secor,D.,Jr.,andDennis,A.,2002,TheCarolinaZone:OverviewofNeoproterozoictoearlyPaleozoicperi-Gondwananterranesalongtheeasternflankofthe southernAppalachians:EarthScienceReviews,v.57,n.3/4,p.299-339.Hibbard,J.P.,vanStaal,C.R.,Rankin,D.W.,andWilliams,H.,2006,LithotectonicmapoftheAppalachianOrogen,Canada-UnitedStatesofAmerica,GeologicalSurveyofCanada,M ap�2096A.1:1,500,000-scale.Hibbard,J.P.,Pollock,J.C.,andBradley,P.J.,2013,Onearc,twoarcs,oldarc,newarc:AnoverviewoftheCarolinaterraneincentralNorthCarolina,CarolinaGeologicalSocietyfieldtripguidebook,265p.Klein,T.L.,1985,GlendonPyrophyllitedeposits�Stops2-10,inFeiss,P.G.,editor,Volcanic-hostedgoldandhigh-aluminarocksoftheCarolinaslatebelt,guidebookforthefieldtripheldinconjunctionwiththe1985falmeetingoftheSocietyofEconomicGeologistsandthe1985annualmeetingoftheGeologicalSocietyofAmerica,Orlando,Florida,p.48-72.LeMaitre,R.W.,Ed.,2002,IgneousRocks:AClassificationandGlossaryofTerms:RecommendationsoftheInternationalUnionofGeologicalSciences(IUGS)SubcommissionontheSystematicsofIgneousRocks:Cambridge,CambridgeUniversityPress,252p.Lesure,F.G.,1981,M apshowingreconnaissancegeochemistryinthegold-pyrophylitebeltofnorthwesternM ooreCounty,NorthCarolina:U.S.GeologicalSurvey,M iscelaneousFieldStudiesM apM F-1301,scale1:48000.McDaniel,R.D.,1976,Applicationofhotspring-fumerolealterationmodeltothegenesisofthepyrophylitedepositsoftheCarolinaslatebelt,unpublishedM .S.thesis,NorthCarolinaStateUniversity,DepartmentofGeosciences,Raleigh,NorthCarolina,75p.Moore,B.R.,1980,Investigationsofafelsicflow,northernM ooreCounty,NorthCarolina,unpublishedM .S.thesis,NorthCarolinaStateUniversity,Raleigh,NorthCarolina70p.Nixon,E.C.,1954,GeologyoftheHarpersCrossroadsarea,southwesternChathamCounty,NorthCarolina:UnpublishedM .S.Thesis,NorthCarolinaStateColege,Raleigh,39p.Olmstead,D.,1822,OnthegoldminesofNorthCarolina,AmericanJournalofScience,v.9,p.5-15.Pollock,J.C.,2007,TheNeoproterozoic-EarlyPaleozoictectonicevolutionoftheperi-GondwananmarginoftheAppalachianorogen:anintegratedgeochronological,geochemicalandisotopicstudyfromNorthCarolinaandNewfoundland.UnpublishedPhDdissertation,NorthCarolinaStateUniversity,194p.Pollock,J.C.,Hibbard,J.P.,andSylvester,P.J.,2010,DepositionalandtectonicsetingoftheNeoproterozoic-earlyPaleozoicrocksoftheVirgilinasequenceandAlbemarleGroup,NorthCarolina:inTolo,R.P.,Bartholomew,M .J.,Hibbard,J.P.,andKarabinos,P.M .,eds.,FromRodiniatoPangea:TheLithotectonicRecordoftheAppalachianRegion:GeologicalSocietyofAmericaM emoir206,p.739-772.Powers,J.A.,1985,M ineralizationandalterationassociatedwithbrecciapipestructures,HawBranchCopperDeposit,M ooreCounty,NorthCarolina,unpublishedM .S.thesis,NorthCarolinaStateUniversity,Raleigh,NorthCarolina,105p.Powers,J.A.,1993,M anuscriptmapoftheRodger�sCreekproject,ChathamandM ooreCounties,BearCreek7.5minutequadrangle,scale:1inch=500feet,unpublisheddata.Reinemund,J.A.,1955,GeologyoftheDeepRivercoalfield,NorthCarolina:U.S.Geol.SurveyProf.Paper246,159p.Samson,S.,Hibbard,J.,andWortman,G.,1995,NdisotopicevidenceforjuvenilecrustintheCarolinaterrane,southernAppalachians:ContributionstoM ineralogyandPetrology,v.121,p.171-184.Samson,S.D.,Secor,D.T,andHamilton,M.A.,2001,WanderingCarolina:TrackingexoticterraneswithdetritalZircons,GSAAbstractswithProgramsVol.33,No.6,p.A-263.Spence,W.H.,1975,AmodelfortheoriginofthepyrophylitedepositsintheCarolinaslatebelt(abstract.).GeologicalSocietyofAmericaAbstractswithPrograms,v.7,536p.Stuckey,J.L.,1928,PyrophylitedepositsofNorthCarolina:NorthCarolinaDepartmentofConservationandDevelopment,Bu letin37,62p.Stuckey,J.L.,1967,PyrophyliteDepositsinNorthCarolina:NorthCarolinaGeologicalSurvey,Bu letin80,scale1:500,000.Tadlock,K.A.,andLoewy,S.L.,2006,IsotopiccharacterizationoftheFarringtonpluton:constrainingtheVirgilinaorogeny,inBradley,P.J.,andClark,T.W.,editors,TheGeologyoftheChapelHil,HilsboroughandEfland7.5-minuteQuadrangles,OrangeandDurhamCounties,CarolinaTerrane,NorthCarolina,CarolinaGeologicalSocietyFieldTripGuidebookforthe2006 annualmeeting,pp.17-21.Wortman,G.L.,Samson,S.D.,andHibbard,J.P.,2000,PreciseU-PbzirconconstraintsontheearliestmagmatichistoryoftheCarolinaterrane,JournalofGeology,v.108,pp.321-338. Equal-AreaSchmidtNetProjections andRoseDiagram Siler VanderBear Bear BilLambert GlendonCity NCHWY ZebBrooks Oldham LittleIndi NCHA Creek Qal Creek Qal Rd. Rd. 902 Rd. Rd. WilsonRd. Creek an 42WY ChathamCo.MooreCo. A' Qal Qal 565' 310' Za Zhdlt(u) Zam(Zhe*?) Zhable Zhable Trc 0' Za 0' Trp Za Za Za Zhime/pl Zhable Zhime/pl Zhime/pl Zhable Zhime/pl Zhime/pl -1500' Zhable -1500' Zhime/plZhime/pl ZhableZhime/pl Zhable Zhable Zhable Zhable Zhable Zhable Zhable Zhable -3000' -3000' Zhable Zhe/pl crosssectionscale-1:24,000noverticalexaggeration GeologicMapoftheBearCreek7.5-MinuteQuadrangle,ChathamandMooreCounties,NorthCarolina.ByPhilipJ.Bradley,AaronK.RiceandBrandonT.Peach GeologicdatacolectedinJune2017throughM ay2018. M appreparation,digitalcartographyandeditingbyM ichaelA.M edina,PhilipJ.Bradley,AaronK.RiceandBrandonT.Peach. 2019 SupersedesOpenFileReport2018-08 Zam(Zhe*?) N.C. ThisgeologicmapwasfundedinpartbytheUSGSNationalCooperativeGeologicMappingProgramunderStateMapawardnumbersG17AC00264,2017andG18AC00205,2018. Thismapandexplanatoryinformationissubmitedforpublicationwiththe understandingthattheUnitedStatesGovernmentisauthorizedtoreproduceanddistributereprintsforgovernmentaluse.Theviewsandconclusionscontainedinthisdocumentarethoseoftheauthorsandshouldnotbeinterpretedasnecessarilyrepresentingtheofficialpolicies,eitherexpressedorimplied,oftheU.S.Government. ThisisanOpenFileM ap.IthasbeenreviewedinternalyforconformitywithNorthCarolinaGeologicalSurveymappingstandardsandwiththeNorthAmericanStratigraphicCode.FurtherrevisionsorcorrectionstothisOpenFilemapmayoccur. GeologicM apoftheBearCreek7.5-M inuteQuadrangle,ChathamandM ooreCounties,NorthCarolina,OpenFileReport2019-06