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CRA

PRECAMBRIAN ORDOVICIAN TRIASSIC

Wood CanyZonabriskie Bonanza King Formation Pogonip Group Monte Cristo Bird Spring Formation Supai Formation Kaibab Formation Fenner Gneiss FormationQuartzite Carrara Formation Sultan Limestone T ONAL . fossiliferous. tan togreylimestone,locallychertywithcalcitefilledfractures.Not green weatheringappearanceofoutcrops.Uppermembersdominantly and siltstonewithminorred-brownsandysiltstone.Characteristicolive- Carrara Formation Bonanza KingFormation Nopah Formation weathered outcropandtendencytofromledges.Notfossiliferous. limestone anddolomite.Characterizedbythedarkcolorofits Sultan Limestone Monte CristoLimestone of silicified,2-3’ to dolomite;minorchert.Oftenrecognizedbythepresence with lessershaleandcalcareoussandstone.Locallyaltered Bird SpringFormation Supai Formation the chertbedsandfossilcontent. fossiliferous withlargewell-presevedbrachiopods.Recognizedby with minordolomiteatbase.Extremelychertyandrichly Kaibab Formation unit intheeastMojave,perhapsremovedbyerosion. dolomite overlainbyredtoorange-brownsandstone.Notacommon Moenkopi Formation shale withthinzonesofchertandcalcareousconglomerate. Chinle Formation Aztec Sandstone Precambrian basement Weakly induratedandpoorlysorted;quartzpebble conglomeratebedsatbase. Wood CanyonFormation Minor crossbedding,generallymassive;prominent ledgeformer Zabriskie Quartzite laterally extensiveintheeastMojave.Notfossiliferous. locally cherty Mountain Membercomposedofthinbeddedblueandwhitelimestone; fractured withcalciteinfractures;minorchert.UpperBanded of blue-graylimestoneanddolomite.Basalstratastronglymottled dolomite andlimestone;locallycherty Shaleistantolightgray steep slopesandverticalfaces.DunderburgShaleliesatthebase. beds ofgypsum.Generallypoorlyexposedondebris-coveredslopes. red-bed sandstoneseenthroughoutthesouthwest. Forms veryprominentridgesandoutcrops;isthe“classic” complex andcutby750-900 Madikes. quartzite andmarble.Intruded by1.0Gagranite,syeniteandcarbonatite fragments andlesserbrachiopods. Pogonip Group by erosion. sporadically presentinthesoutheasternMojave;perhapsremoved Although laterallyextensivethroughouttheGreatBasin,only Characterized bysolutionkarstfeaturesnearthetopofunit. . Thisunitisaprominentridgeformerandthemost Chaetetes -interbeddedtantobuffdolomiteandlimestone. -redtopinksandstoneandshalewithafewsporadic -massivelycross-beddedredsandstone. -redshalysandstone,red,brownandgreen -massivetothickbeddedtanbuffdolomite.Forms -dark,smokygray -tantoverylightgray -lowermemberscomprisedofgreentobrownshale -whitetolighttan,wellsortedandstronglyindurated. -tantobuffthin-beddedlimestonewithminor -predominantlymedium-graylimestone , calcareousandslightlysiliceous. -stronglyfoliatedgneiss withminorinterbedded -lightgray corals. -lowerPapooseLakeMembercomprised -redbrowncross-bedded,arkoisicsandstone. , generallymassive . , thintomedium-bedded Abundant crinoid , thick-beddedlimestone . MIOGEOCLINAL PRECAMBRIAN CAMBRIAN

Fenner Gneiss Crystal Springs Formation Beck Springs Dolomite Kingston Peak Formation Knoonday Dolomite Johnnie Formation Stirling Quartzite Wood Canyon Fm. STRATIGRAPHIC GENERALIZED EAST MOJAVE Wood CanyonFormation Precambrian basement intruded bydiabasesills(1.08Ga). by mudstone-quartzsandstone;uppermemberthick-bedded limestone shale/mudstone; middlemembermassivestromatoliticlimestoneoverlain Crystal S Beck SpringsDolomite to beadiamictite. siltstones gradingupwardintoaconglomeratenowgenerallyrecognized Kingston PeakFormation Noonday Dolomite overlies theoolite. gray shalegradingupwardintodiamictiteconglomeratelocally limestone, isanimportantmarkerbed.RainstormMember siltstone andconglomerate.JohnnieOolite,athinblue-grayoolitic Johnnie Formation Stirling Quartzite complex andcutby750-900 Madikes. quartzite andmarble.Intruded by1.0Gagranite,syeniteandcarbonatite locally oolitic. siliceous dolomitewithminorcross-beddedquartzite. massive quartzite;middleunitisablackcarbonaceoussiltstone. Cal P COLUMN D.R. JESSEY prings Formation oly -Pomona -lowerandupperunitsaredarkgraytopurple -creamtogray -darkgrayquartziteinterbeddedwithdolomite, -blue-graymassivetowelllaminateddolomite; -stronglyfoliatedgneisswithminorinterbedded -sequenceofinterbeddedsandstonesand - seecratonaldescription. -basalarkosicsandstonegradingupwardinto , poorlybeddedalgaldolomiteand, , adark