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GEOLOGIC JOURNEY Answer Key The Great Lakes Chapter 1: Niagara Falls 1.1.3 Roughly 1.5 metres 1.1.4 17 million litres per minute – the largest in the world 1.1.5 First place in the 19th century where there was a fairly accurate estimate of past time 1.1.6 36,000, a few thousand years old, 4.5 billion years 1.1.7 Continental and oceanic crust, mantle Chapter 2: The Legacy of the Grenville Mountains 1.2.3 As a result of the collision of North America (known as Rodinia at the time) and another piece of oceanic crust 1.2.4 Huge – the size of the Himalayans; 10 kms high, covered with snow, glaciers draining away from the mountains 1.2.5 The crust rebounded when released from the weight of the ice causing further erosion. Eventually, the roots of the Grenville Mountains rose up and were exposed. 1.2.6 A combination of pressure and heat 1.2.7 All crustal rocks contain radioactive elements. When you put one layer on top of another, the heat is trapped and begins to build. 1.2.8 Few places in the world exist where you can actually view the Earth’s building blocks; in this case, the very thick middle of a mountain belt. 1.2.9 The rocks contain no primary features. All we know for sure is that they were all hot. 1.2.10 Uranium-lead dating 1.2.11 The original age of the rock and the time of the melting 1.2.12 One grain of sedimentary rock, weighing much less than one gram 1.2.13 The rocks have been painted by some of the greatest painters in Canadian history, and contemporary artists continue to paint the rocks. Chapter 3: Salt Mines: An Underground Laboratory 1.3.3 New volcanic mountains arose, creating a number of “sinks” all over the continent. About 400 million years ago. 1.3.4 It would be the same climate that exists in the Caribbean today 1.3.5 Created salt deposits that are mined today 1.3.6 400 million years old 1.3.7 The white horizontal lines indicate years of extreme heat. The black lines indicate cooler, rainier weather. 1.3.8 They drill cores.

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GEOLOGIC JOURNEY

Answer Key

The Great LakesChapter 1: Niagara Falls1.1.3 Roughly1.5metres1.1.4 17millionlitresperminute–thelargestintheworld1.1.5 Firstplaceinthe19thcenturywheretherewasafairlyaccurateestimateofpasttime1.1.6 36,000,afewthousandyearsold,4.5billionyears1.1.7 Continentalandoceaniccrust,mantle

Chapter 2: The Legacy of the Grenville Mountains1.2.3 AsaresultofthecollisionofNorthAmerica(knownasRodiniaatthetime)andanother

pieceofoceaniccrust1.2.4 Huge–thesizeoftheHimalayans;10kmshigh,coveredwithsnow,glaciersdraining

awayfromthemountains1.2.5 Thecrustreboundedwhenreleasedfromtheweightoftheicecausingfurthererosion.

Eventually,therootsoftheGrenvilleMountainsroseupandwereexposed.1.2.6 Acombinationofpressureandheat1.2.7 Allcrustalrockscontainradioactiveelements.Whenyouputonelayerontopof

another,theheatistrappedandbeginstobuild.1.2.8 FewplacesintheworldexistwhereyoucanactuallyviewtheEarth’sbuildingblocks;

inthiscase,theverythickmiddleofamountainbelt.1.2.9 Therockscontainnoprimaryfeatures.Allweknowforsureisthattheywereallhot.1.2.10 Uranium-leaddating1.2.11 Theoriginalageoftherockandthetimeofthemelting1.2.12 Onegrainofsedimentaryrock,weighingmuchlessthanonegram1.2.13 TherockshavebeenpaintedbysomeofthegreatestpaintersinCanadianhistory,and

contemporaryartistscontinuetopainttherocks.

Chapter 3: Salt Mines: An Underground Laboratory1.3.3 Newvolcanicmountainsarose,creatinganumberof“sinks”alloverthecontinent.

About400millionyearsago.1.3.4 ItwouldbethesameclimatethatexistsintheCaribbeantoday1.3.5 Createdsaltdepositsthatareminedtoday1.3.6 400millionyearsold1.3.7 Thewhitehorizontallinesindicateyearsofextremeheat.Theblacklinesindicate

cooler,rainierweather.1.3.8 Theydrillcores.

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1.3.9 Itwassovaluedthatwarswerefoughtoverit.Soldiersusedtobepaidinsalt.Itwasanimportantpreservativeformanyyears.

1.3.10 Thattherewasasuddenflood1.3.11 Thisiswherethewavesofthewaterlappedagainsttheshorelinemillionsofyearsago.

Chapter 4: Ice Sheets and Glaciers1.4.7 TheyscouredouttheMichiganbasin(ofsalt)andcreatedtheotherhugecratersthat

becametheGreatLakes.1.4.8 ApinkpebblefromtheCanadianShield,fartothenorthofthebluffs1.4.9 Glacialmeltwater1.4.10 Twelveto15millionyearsago1.4.11 TheeffectofclimatechangeonwaterlevelsbetweenGeorgianBayandLakeHuron1.4.12 Hebelievesitwillcontributeinformationabouttheclimate8500yearsago.1.4.13 LargerthanNiagaraFalls1.4.14 LocatedbetweenGeorgianBayandLakeHuron

The RockiesChapter 1: Plate Tectonics – Formidable Forces2.1.1 Volcanismcouldhaveaddedsomenewrockfromvolcanoes(butnotenoughforall

ofthelandthatdeveloped);areasbelowsealevelcouldhavebeenupliftedformingtheland(wewouldseemostlydeepseasedimentaryrocks,notthecomplexmixtureofrocktypes,overtheCordilleraifthiswerethecase);strikeslipfaultingcouldhavebroughtlandfromelsewhere(somewasaddedthisway).MostofthelandwestoftheoriginalwesternedgeofNorthAmericaisinfact“exotic”materialaddedasaresultofplatesconvergingwiththecontinent.

2.1.2 HowweretheRockiesmade?Whyaretheyfolded?Whatkindofforcewasstrongenoughtobendsolidrock?WhyisthereoilandgoldtrappedintheUSRockiesandnotintheCanadianRockies?Howmuchlongerbeforetheglaciersmeltaway?

2.1.3 Rockatthepeaksofmountainswasonceatthebottomofoceans.ThefoldedandfaultedrocksinthejaggedpeakswereonceasflatasthePrairies.TheRockieswereoncecompletelycoveredinice.

2.1.4 Folding(plasticdeformation)andfaulting(brittledeformation)2.1.5 Exoticrock:rockthatdidnotformwhereitisnow.Exoticrockhasbeenmovedfrom

somewhereelseandthenscrapedoffasubductingplate.Itwillbequitedifferent,overanabruptcontact,totherocksthatitendsupbeingnextto.

2.1.6 Subduction:anoceanicplatethatdescendsbeneathacontinentaloranotheroceanicplate.2.1.7 Basalts

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2.1.8 Extremelythicksequenceofbasalts(insomeplacesonVancouverIsland.morethan6kmsthick).Therocksaredarkcolouredandheretheyhavebeenerodedtoformtheseacavesandimposingcoastalcliffs.

2.1.9 Formedfrommagmaeruptingrepeatedlyatvolcanicislandsinthemiddleofanocean2.1.10 HawaiioroceanplateaussuchasHessRise.2.1.11 Thebasaltsareathickpileoflavasthatwerepartofanoceanicvolcanicisland.The

volcanicislandwascarriedtowardsNorthAmericaonaplate.TheplatesubductedbeneathNorthAmericaandwhenthevolcanicislandridingalongontheplatecollidedwithNorthAmerica,itwasscrapedoffandaccretedtoNorthAmerica,formingthebasaltsatHesquiat.

2.1.12 • TheoldNorthAmericanmarginwasroughlywheretheAlberta/BCborderistoday.• HesquiatisonthewesternedgeofVancouverIsland,justNorthofthePacificRimNationalPark.

• Wrangellia.• Sixteenaccretedterranes.• Theyaretypicallylongnarrow,squishedlookingbeltsofrock.

2.1.13 • Theoceancrustsubductsbecauseitisthinneranddenserthanthecontinentalcrust.

• Earthquakes(thereisalmostoneperdayrecordedonVancouverIsland),volcanoes(e.g.MtMeager,MtSt.Helens),upliftandcompression-producingmountains(accompaniedbyfoldingandfaulting).

• Whenterranescollidetherearehugeforcesassociatedwiththecollisions.ThesecompressionalforcescausethesedimentsandrocksattheedgeoftheNorthAmericanplatetobuckle(fold)andbreak(fault)astheyarecompressed.

• Everytimeaterraneisadded,anewepisodeoffoldingandfaultingassociatedwiththecollisionoccurs.

2.1.14 • Thedarksoftdrinkbubblesgentlyovertheedgeofthecup,whilethecornsyrupbuildsuppressureandthenexplodesoutmoredramatically.

• The‘magmas’havedifferentviscosities.Thecornsyrupmagmahasahighersilicacontentandisthereforethickerandflowslesseasily–highviscosity.Thesoftdrinkmagmahasalowviscositybecauseofthelowersilicacontent.Theselowviscosity,moremafic(richerinironandmagnesium)magmasalsotendtobehotterandlessgas-richthanthehighersilica(felsic)magmas.Viscousmagmastendtoformhighlyexplosivesteepsidedvolcanos(e.g.Mt.Fuji)andmagmaswithlowviscosities(runny)tendtoformflatsheets(plateausorvolcanoeslikeMaunaLoainHawaii).

• ThelowviscositymaficmagmawouldhaveformedtheHesquiatbasalts.• TheHesquiatbasaltsweren’tsubductedbecausetheyareverythick(andnotquite

asdenseasnormaloceancrust).Theoceancrustisonaveragearound6kmthick.Ifoceancrustwithanadditional5or6kmthickpileofbasalticlavasreachthesubductionzone,thebasaltswillbescrapedoffasterranes.

• TheHawaiianIslands,LineIslandRidge,HessRise,ShatskyRise(theselastthreearealloceanplateaussimilartowhattheHesquiatbasaltswouldhavebeenlikebeforetheycollidedwithNorthAmerica).

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Chapter 2: From Sea to Sky: Folding and Thrusting2.2.1 Oneexamplewouldbetopushatbothendsofapadofpaper–thepadwillbuckleor

fold.Anotherwaywouldbetotakeasoftgranolabarandsqueezetheendstowardseachother.

2.2.2 Pushingbothendsofastickwithyourhands(thestickwillbreak)ordroppingacuporplateonthegroundisanotherexampleofbrittledeformation.

2.2.3 YouwouldexperiencedifficultieswithreproducingthescaleoftheprocessesandalsowiththeactualconditionsintheEarthsuchasconfiningpressure,duetodepthundertheEarth’ssurfaceaswellastemperatureandtheamountsofforceinvolved.

2.2.4 AllofthemountaintopographyshownintheRockiesisaresultoffoldingandfaulting.Theverticalsedimentarylayersarepartsoffolds,andmanyoftheseeminglyhorizontallayersarepartsofhugefoldsthattoppledoverandarenowlyingflat.Thefaultsthataremostcommon(e.g.inMtYamnuska)arethrustfaults.Theseareverylowangledfaults,alongwhichlargeblocksofrockmovedtowardstheeastastheNorthAmericanplatecollidedwithterranesandcausedvastamountsofhorizontalcompression.

2.2.5 Rocksthatbreakarebrittle.Generallythisiswhathappenstorocksnearthesurfacewhentheyexperiencestresses.Whenrocksareunderalotofconfiningpressure(becausetheyareverydeepinthecrust)andalsoarealothotter,theytendtobehaveinaductileway,likeplastic.

2.2.6 • Image2.1–layersarelyingflat• Image2.2–Layersarelyingflatandyoucanseethecrestornoseofthefold

towardstheleftofthepicture.Axisofthefoldisclosetohorizontal(recumbentfold)• Image2.3–Thelayersagainarefoldedandyoucanseethecrestofthefoldtoward

thetopleftofthephoto.Theaxisofthefoldinalsohorizontal,sothisisarecumbentfoldaswell.

• Image2.4–layersaretiltedsteeply• Image2.5–layersarealmostvertical• Therocklayersinthefirstthreephotosarebentintofoldsthatarenowlyingflator

closetohorizontal,exceptforthenoseofthefold.Thelasttwophotosshowrocklayersthataresteeplytiltedandalmostvertical.

2.2.8

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2.2.9 ThefirstthreephotoswouldbefromtheMainRangesandthelasttwofromtheFrontRanges.

2.2.10 TheoldestaretheWesternRanges,followedbytheMainRanges,thentheFrontRanges,andtheyoungestaretheFoothillseastoftheFrontRanges.Thecompressionalforcefromtheterranescolliding,bulldozingtheRockies,iscomingfromthewest.Allofthethrustfaults(seecrosssection2.1)showmovementofthethickfoldedsequencesofrockalongthethrustplanesfromthewesttowardstheeast.

2.2.11 • Thelimestonesweredepositedapproximately520millionyearsago.Muchlater(around75millionyearsago)theshaleandsandstoneweredepositedontopofthelimestone.

• Compressionalforcescausedthelimestoneandshale/sandstonepackagetobreak(thrustfault)andaslabofthepackagewaspushedovertopofthesandstonealongthethrustfault.

• Erosionthenworeawaymostofthetopsandstoneandshaleleavingtheolderlimestonelyingontopoftheyoungershaleandsandstone.

2.2.12 Limestoneformedinashallowwarmocean.Sandstoneandshalesformedfromsedimenterodingfromrisingmountainsandterranestothewest.Thelimestoneandoverlyingsandstoneshalepackagesbrokealongalowanglefaultorbreak(higherintheeastandlowerinthewest)sotherockmoveduptheslopeofthefault.Thehugeheightsbuiltupbythisprocesswerethenwornawaybyerosiontoformthemountainsseeninthephotos.

2.2.13 Sketchesoftheabove.2.2.14 Themostimportantwaythatstratigraphersdeterminetheageofspecificrockunitsis

bylookingatthefossilstheycontain.AssemblagesoffossilsfoundatanyageofEarthhistory(e.g.dinosaursintheMesozoic)areuniquetothattimesotheycanbeusedtorelativelydaterockunits.Togetanumericalagerocksmustberadiometricallydated.

2.2.15 Limestoneismostcommonlymadefromtheshellsorhardpartsofmarineorganismssuchascorals,clams,spongesorplankton.Mostlimestonesforminshallow,warmtropicalorsub-tropicaloceanareas.LimestonesareformingtodayinplacesliketheGreatBarrierReef,theCaribbeanandBelize,aswellasinthedeepoceansfromtheaccumulationontheoceanfloorofthecalciteshellsofcertaintypesofplankton.

2.2.16 Forexample,asketchofawarmtropicalreefandadjacentlagoonandbeach.2.2.17 Thesketchoftheoriginalmountainswouldshowsomeveryhigh,jaggedandsteep

mountains,whilethepresent-daysketchwouldshowmuchlower,moreerodedmountains.Thepresent-daysketchshouldincludesomeerosionalfeaturesassociatedwithglacialprocessessinceglacialerosionhasbeenveryimportantfortheRockiesoverthelast2millionyears.

2.2.18 • Itwillvaryeverytimeyoudotheexperiment,butthepossiblestructuresthatyouwouldproduceareallthevarietiesoffoldsincludinganticlines,synclinesandrecumbentfolds.Youmayalsoproducefaults(normaliftheplaneofbreakageisclosetovertical)orthrustfaultsifitisaflattishbreak. TheverticallayersofsandandflouraresimilartothestructuresoftheFrontRanges;otherswithmoreflat-lying

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layersorfoldsontopofthrustfaultsaresimilartowhatyouwouldseeintheMainRangesoftheRockies.

• Withthisexperimentyouwillbeabletoproducebothplasticdeformation(folding)andbrittledeformation(faulting)bymanipulatingtheoozeindifferentways.

• Gentleprolongedpressurewillcausetheoozetoflow(fold).• Moreforceoverashorttimewillcausetheoozetobreak(fault).• Ithardensandbreaksifforceisappliedquickly.• Compressionalforcesappliedtorocksovermillionsofyearswillcausethefolding

weseeintheRockies.Theaddedforcesassociatedwithcollisionsofterraneswilloftencausemajorepisodesoffaulting,suchasthethrustfaultsweseeintheRockies.

2.2.20 Earthquakes,hotsprings

Chapter 3: Rocky Mountain Resources and Land Use2.3.1 Suggestionsmayincludetheirparks,naturalbeauty,resources,outdooractivity

potential.2.3.2 ProximitytotheRockieswouldmeantheycouldeasilyaccesstheparksandoutdoor

experiencesthattheRockiesoffer.Provincially,theRockiesareimportantforrevenuefromtourismandresourceextraction,andtheyalsopresentsignificantbarrierstotransportationofgoodsfromEasttoWest.Thefurtherawayoneis,thelessdirectimpacttheRockieswouldhave,eitheronanindividual,provincialornationallevel.However,regardlessofproximitytherewillalwaysbetherecognitionthattheRockiesrepresentanimportantreserveofnaturalbeautyandwildernessareassetasideforallCanadians.

2.3.3 • RundleRock–quarriedfromMountRundlenearBanff;nowquarriedjustEastofCanmore/buildingstone,e.g.BanffSpringsHotel

• PaskapooSandstone–quarriedlocally/buildingstoneforschools,banks,churchesandgovernmentbuildingsinWesternCanadaintheearly1900’s.

• PalliserLimestone–minedatExshawandCadomin/cementmaking• WapiabiShale–minedfrombelowMountYamnuska/usedatExshawforthe

productionofcement• Gypsum–minedattheElkhornquarrynearWindermereandtheLussierRiver

quarrynearCanalFlats/usedtomakewallboard(drywall)andcement• Dolomiticshale–BanffFormation/usedtomakemineralwoolnearExshaw.• Ordovicianquartzite–minednearGolden,B.C./usedasasourceofhigh-grade

silica(e.g.Forglass)• Ammolite–outercoatingonsomeJurassicandCretaceousammonites/usedfor

jewellry• Coal–minedatCanmorefromthelate1800’suntil1979/usedbytheCanadianPacificRailwaytofuelcoal-poweredlocomotives,andtodaycoalprovidesmorethan80%ofAlberta’selectricalenergy

• OilandGas–JumpingPoundFoothillsGasField,ElmworthDeepBasinGasFieldintheRockyMountainFoothills(mostofAlberta’soilisfromtheplainstotheeast)/

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naturalgas,energy,fuel(e.g.JumpingPoundgasfieldsuppliesoverhalfthenaturalgasneedsofCalgary)

2.3.4 Someideasmightbewilderness,nature,tourism,physicalactivitiessuchasskiingandhiking,employment,vacationing,rockclimbing,hotsprings,viewingofwildlife,hunting,etc.

2.3.5 Forexample,downhillskiing.Thecontributingcharacteristicswouldbesteepslopes,accessibility,highmountainsforlongruns.ThepotentialimpactontheRockieswouldbefromdevelopment(roads,hotels),morepeople,lossofpristinenaturalenvironment(skiruns,lodgesetc.).

2.3.6 DesignationofWorldHeritageSiteshttp://whc.unesco.org/en/list/304andcreationofparkswhichlimitdevelopment

2.3.7 Buildingofroads,houses,facilities,wastedisposal,pollution,barrierstowildlifemigrationbecauseofsettlements,roads,railways,slopeinstabilitiesassociatedwithrailwaycuts,logging,resourceextraction

2.3.8 Pristinewildernesswithnodevelopmentwillallowthenaturalenvironment,includingthewildlife,tobepreservedforfuturegenerations.Allowingdevelopmentwillaltertheenvironmentthatdrewpeoplethereinthefirstplace,butwillalsoprovidejobsandallowpeopletoenjoyandbenefitfromtheirexperienceofthewildernessdirectly.

2.3.9 Mines:• NorthwestB.C. EskayCreek–gold,silver Endako–molybdenum Huckleberry–copper,molybdenum TableMountain–gold• CentralB.C. KemessSouth–copper Gibraltar–copper,molybdenum MountPolley–copper,gold,silver• SouthCentralB.C. HighlandValley–copper,molybdenum,gold,silver• SouthwestB.C. MyraFalls–copper,zinc,silver,gold

Chapter 4: Erosion on a Grand Scale2.4.1 TheHimilayasarehighest,steepestandmostrugged.TheAppalachiansarelowest,

mostroundedandleastrugged.2.4.2 Mountainsthatareintheprocessofbeingformed,e.g.theHimalayas,willbesteeper

andhigherbecausethetectonicforcesthatarepushingthemuparestillactive.Thelongeragoamountainrangeformed,themoretimetherehasbeenforerosiontowearawaythepeaksbyremovingrock,grainbygrainorpebblebypebble.BoththeAppalachiansandtheRockieswhentheyfirstformed(~340myago,and~60myagorespectively)wouldhavelookedverymuchliketheHimalayastoday.

2.4.3 Criteriamightbeageofthemountainsi.e.whentheyformed(AppalachiansinthePaleozoic,theRockiesintheMesozoic,andtheWesternGhatsintheHimalayasarestillforming).Othercriteriacouldbebythehighestpeakineachrangeorhowroundedorruggedthemountainsare,bothofwhicharerelatedtotheageandthe

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amountoftimethaterosionhasbeenwearingtherocksaway.Othercriteriamightbewhetherthemountainshaveglaciersornot(dependssomewhatonheight,rainfallaswellaslatitude),orthetypesofrocksthemountainsaremadeof.

2.4.4 • GlaciationhasshapedtheRockiesthrougherosionaswellasdeposition.• Erosionalfeaturesinclude:Ushapedvalleys,hangingvalleys,cirques,arêtes,

horns,glaciallakes,polishedrock,grooves,rochemoutonee.Glacialdepositionalfeaturesincludemoraines(terminal,recessional,lateral,medial),otherdepositsoftill,drumlins,eskers,outwashplains,erratics.

2.4.5 Sketchesofthedepositionalfeaturesnotedabove2.4.7 Themudstonewouldlikelybetheleastresistant,withthesandstonenextandfinally

thelimestonewhichisthemostresistant.Theseresultsmatchupwellwithwhatyouseeinthevideo,sincemanyofthehighestpeaksaremadeoflimestone.Theexposuresofshaleormudstoneareoftencoveredwithvegetationandappearmoreerodedandrecessive.Sandstoneisinbetween–harderthanshalebutsoftergenerallythanlimestone.

2.4.8 Theyaremeasuringthethicknessoftheice.Thiswillenablethemtoestimatethetotalmassoftheiceandovertimeseeifthetotalmassisincreasingordecreasing,andfromthiswhethertheicesheetismeltingawayorgrowing.Theyarealsomeasuringthethicknessofthelastwinterlayerofsnowwhich,whencomparedovertheentireicesheetwiththeamountofmeltwaterlost,willtellthemiftheicesheetisgettingsmaller.

2.4.9 Vastamountsofmeltwaterflowingawayfromtheiceinriversandwaterfalls,andthehugecrevassesintheglaciers,andthemoulins.ThemorainesatthefrontedgeoftheAthabascaglacierarebeingdepositedfurtherandfurtherupthevalleyandtheiceisfillinglessofthevalleyastimegoeson.

2.4.10 LittleisknownabouttheicesheetsinCanadabetween2millionyearsand135,000yearsago,howeverstudiesofoceancoressuggestthatthereweremorethan50glacialandinterglacialcyclesduringthattime.Researchsuggeststhataround135,000yearsagotherewasamajoricesheet,againaround70,000yearsago,anotheradvancearound20,000,andanotheraround1200yearsago.

2.4.11 ThereweremajorglaciationsintheEarth’spast:duringthelatePrecambrian~900millionyearsago(SnowballEarth);inthelateOrdovician~430millionyearsago;Carboniferous~340millionyearsago;andinthePleistocenestartingaround2or3millionyearsago(theglaciationswhichaffectedtheRockies).

2.4.12 Scientistshavetolookatolderrocksforevidenceoftheseolderglaciations.Theywouldlookforancienthardenedtilldeposits,evidenceofglacialgougesandstriationsonthepebbleswithinthesetillsordiamicts,hardenedsedimentsassociatedwiththeancientmeltwaterstreamsflowingfromtheglaciers,aswellasevidenceofancientglaciallakesthatwouldhaveproducedvarves.Evidencecomesfromallovertheworld;forexample,theeffectsoftheCarboniferousglaciation(tillsandoldrockstriations)arewellexposedintheSaharadesertofAfrica.

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The Canadian ShieldChapter 1: Meet the Torngats3.1.2 Evidenceofmarinelifecanbefoundatthetopofmountains.Thishappensover

extremelylongperiodsoftime.Thepresenceofzirconintherock.3.1.3 Providesanopportunitytolearnhowoldtherocksareandunderstandtheprocesses

thatformedthem3.1.4 Themineralzircon3.1.5 Zirconscontainsmallamountsofuraniumthatdecayatapredictablerategivingthe

ageofthemountainbuildingevents.3.1.6 Theexistenceofsandstonewithripplesinit,andthemineraldepositofironpyrite3.1.7 Coalisderivedfromorganicmaterials.3.1.9 PriortoPangaeathereistheideathatthecrustoftheformingcontinentswastoo

fragiletosupportthestructure.Astheplanetcooled,largermassesoflandcouldform.

Chapter 2: The Geology of Human Activity3.2.1 Platetectonics;subductionevents3.2.3 TheRamaChertwasusedtomaketools.3.2.4 • Human:toolmaking;sacredconnection;foundasfarsouthasMaine(partofatrade

system?)• Geologic:containsearly,organiclife;underwentagreatamountofheatandcooled

quickly3.2.5 Higheraltitudesamplesarelesslikelytobecorruptedbyyoungervolcanicrocks,and

morelikelytorevealanaccurateageofthemountains.3.2.6 usinglasertechnologyandanalysinggasesfromthemineral3.2.7 thepresenceofdifferentlayersinthecrystalbeinganalysed

Chapter 3: The Search for Gold3.3.1 True;True;True;True;False;True3.3.2 Highlydeformedrocks,andevidenceofgoldbearingfluidsmovingthroughtherock

(plumbing)3.3.3 Gneissformationsarecausedbyhotplasticrockgettingsqueezedbytectonicplates

rammingintoeachother.3.3.4 Itindicatesfluidsthatwouldhavemovedgoldthroughtherock.

Chapter 4: The Sudbury Basin and Manicouagan3.4.3 ContinentalshieldareathatwasformedduringtheArcheanera

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3.4.4 MeteoriteshittheEarthandpunchedaholeintotheEarth’scrustallowingthemantletofillupthebasin.Shockwavesshatteredtherockandnickel-bearingmineralsworkedintothefracturedsurfaceandwereburiedunderthepulverisedrock.

3.4.5 SimilarrockcompositionalongtheShieldwouldexperiencethesameconditionsduringameteoriteimpact.Thesizeandtheageoftheimpactwouldalsodefinethepotentialwealthatotherimpactsites.

3.4.7 Coresamplesrevealthesecretsoftheunderlyingstructureoftheareaandallowformodelstobedevelopedthatwouldbeusefulinfindingmineraldeposits.

Chapter 5: Diamonds: The New Resource3.5.2 Theerosiveactionoftheglaciersremovedoverburdenandrevealedshowingsof

diamonds.3.5.3 Disadvantage:takesalotoftime.Advantage:abletosurveytheareacloselyand

understandthesearchareamoredirectly.3.5.4 Millionsofyearsofglaciationandothererosiveforceshavedistributeddiamonds

acrossthelandscape.3.5.5 Theoriginalsourceofthediamondshavebeendeformedandeffectivelyerasedfrom

thelandscape.Onlycluesexistandthesemustbefoundandinterpretedcorrectlytolocatethetreasure.

The AppalachiansChapter 1: Coal: Getting It Out of the Ground4.1.1 Themostlikelysourceswouldbenaturalgas,oil,electricity,solar,andwood.4.1.2 Themostlikelysourceswouldhavebeencoal,wood,electricity,andoil.4.1.3 Themajorreasonsforshiftingfromcoaltonaturalgas,probablythetwomostcommon

urbanenergysources,wouldincludelowercost,cleanerburning(i.e.lessdustandnoashes),lessstoragespaceneeded,andeasiertoregulatetheburningofthefuel(i.e.abletousethermostats).

4.1.4 Energysourcesmightmovemoretoimprovinghomeinsulation(theconservationoption),solarheating,andgreateruseofelectricalenergyderivedfromsolar,wind,andnuclearpower.

4.1.5 Fromanthracitetolignitethemajorchangesincludealowercarboncontent,reducedhardness,lowerheatingvalueperunit,andfromuseinhomeheating/waterpurificationtoelectricalgeneration.

4.1.6 Anthracitehadhighcarboncontentwhich,afterburning,resultedinharderwasteandlessash.Anthracitecouldbemoreeasilystoredandhandledwithoutbreakinguporgivingoffdustandcontainedmoreenergyperunitofweight.

4.1.7 Threetypesofcoalare:anthracite,lowtomediumvolatilebituminous,andhighvolatilebituminous.

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4.1.8 Anthraciteinthefoldedregion,bituminousintheunfoldedregion4.1.9 ThefoldingandcompressioncausedwhentheAppalachiansformedprobably

convertedthecoalfrombituminoustoanthraciteineasternPennsylvania.4.1.10 Theanthraciteregionwouldbemostdifficultsincethecoalbedsarefoldedinsteadof

beinglevellayers,makingitharder,moreexpensive,andmoredifficulttominesincemanydifferentshaftswouldbeneededtodigoutthecoalinfoldedrock.Inunfoldedrocks,itwouldbeeasierandcheapertominealonglevelcoalseamssincefewershaftsordriftswouldbeneededtogetatthecoal.

4.1.11Time Period Type of Mine Number of

MinersHuman Risks Environmental

RisksEarly20thCentury

Drift/shaft 2000-3000 Highdeathrates–30000miners

Small–mineswereunderground

Early21stCentury

Strip 10-20 Low–truckdriversandcraneoperatorsworkaboveground

High–strippingrocklayersofftopsofmountainstogetatcoal

4.1.12 Changesresultedfromincreasedmechanizationreducinglabourdemands,andlargermachinesincreasingtheabilitytostriplargequantitiesofrocktogetatcoalseams.

4.1.13 Decisionshouldbebasedonthenumbersofdeathsofminersinthe20thcenturyduetomining(undergroundminingdisastersstilloccurintheUS,China,andothercountriestoday)andthepracticeofstrippingoffwholemountaintopstogetatcoalseamsinthe21stcentury.

4.1.14 Studentsshouldusethefactualevidenceprovidedbythevideoandtheiranswerstoearlierquestionsintheirarguments.Accuracyandrelevanceofprovidedfactualjustificationsshouldbeinevidence.

4.1.15 AreaswouldstillincludetheUnitedStates,China,Poland,MexicoandAustralia.Agoodwebsitetoreferstudentstoishttp://en.wikipedia.org/wiki/List_of_disasterswhichhasanextensivesectionlistingMiningDisasters.

Chapter 2: Colliding Plates, Making Mountains4.2.1 Movingplatescollidingandseparatingfromoneanotherovergeologictime4.2.2 Acollisionofcontinentswouldcrush,bend,andforceuprocksalongtheedgeofthe

platetoformhigh,ruggedmountainsduetofolding,faulting,andvolcanicactivity.4.2.3 Real-lifesimulationswouldincludecarsand/ortruckcollidingwitheachotherorwith

polesorbridgeabutments,orshipscollidingatsea.4.2.4 Twocontinentshavemovedtowardsoneanotherduetoplatemovementsand

collided.Theresultwasabendingandbreakingofsedimentaryofotherrocklayersandpushingupoftall,ruggedmountains.Astheleadingedgeoftheoneoftheplatesdescendedintothemantle,itmeltedandmoltenrockflowedupwardsthrough

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cracksinthecrust,causedbythecollision,toformvolcanicfeatures.Theseeruptionsaddedevenmoreheighttothemountainchainformedbythecollision.Eventuallythecontinentswere“welded”togetheralongthelengthofthenewmountainrange.

4.2.5 TheycouldbeappliedtotheformationoftheHimalayaMountainswhereIndiaiscollidingwithAsia.

4.2.6 Himalayas Collision Boundary Sketch Map

4.2.7 “BreakupofPangaea”wouldbeaddedtothechartintheJurassictimeframewithinthe

MesozoicEra.“FormationofPangaeaandAppalachianswouldbeaddedtothechartintheDevoniantimeframeinthePaleozoicEra.

4.2.8 TheNorthAmericanPlatecollidedwiththeEurasianandAfricanPlates,pushinguptherocksalongtheiredgestoformtheAppalachianMountains.

4.2.9 MountainsinnorthwestAfrica,Greenland,andnorthwestEuropewerealsoformedatthesametimeastheAppalachians.

4.2.10 ThesupercontinentofPangaeastartedtoseparateorbreakupafteraperiodof200millionyears.

4.2.11 ShenandoahMountainsarelowerandroundedcomparedtothemuchhigherandveryruggedmountainsthatformed370millionyearsago.

4.2.12 ThecollisionoftheAfricanandNorthAmericanPlates

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4.2.13 Evidenceincludes:foldedrocks,ancientfossilsfoundinsedimentaryrocksonmountaintops,lackofrocksofayoungeragethanthoseofthemountains,andalteredormetamorphosedrocksformedatgreatdepththatarenowfoundon,orverynear,thesurfaceoftheEarth.

Chapter 3: New Technologies, New Theories4.3.1 • Hypothesis–aproposedexplanationmadeonthebasisofavailableorlimited

evidenceandusedasaguidetofuturestudyorinvestigationtoproveitsaccuracyoracceptability.

•Theory–awidelyacceptedexplanationthathasbeenverifiedusingavailableandvalidatedevidence,anexplanationofeventsorprocessesthatbestfitsknownfacts.

4.3.2Case Study/Researcher

Hypothesis Technology In Use

Facts Collected Using Technology

Result of Hypothesis Testing

MontmorencyFalls–StephaneMazzotti

MovingapartoftheplatesalongSt.LawrenceValley

HighlyaccurateGPSequipment

Platesaremovingapartatafewmmperyear

Provesthatplatemovementcouldcauseearthquakesinfutureinthisregion

NewMadrid–MartitiaTuttle

Majorearthquakesoccurapproximatelyevery500yearsinsteadoftheformerlyaccepted1000yeartimeperiodintheNewMadridarea

Helicopterflight,radiocarbondating,

Dateswhensandblowsoccurred,indicatingmajorearthquakesintheregion

Provesthatthemajorquakesoccurapproximatelyevery500yearsonaverage

NorthCarolina/Newfoundland–JamesHibbard

Twomicroplates(CaroliniaandAvalonia)collidedwithNorthAmericatoformtheAppalachianMountainsinNorthCarolinaandNewfoundland

Lasertechnologytodatezircons

DatesofcollisiontoformmountainsinNCarolinaandNewfoundlandweredifferent

Provestwomicroplateswereinvolved,ratherthantheformerlyacceptedideathatonlyonemicroplatewasinvolved

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4.3.3. Itisreferredtoasatheory.4.3.4 Itismostlikelythatsometheorieswillbethrownoutorrevisedandthatnew

hypotheseswillbeproposedandprovenasaresultofnewevidenceobtainedthroughtheuseofnewandmoresophisticatedtechnologicaldevices.

Chapter 4: Want to be an Earth Scientist?4.4.1 Studentscouldsuggestawidevarietyofperceivedtraits,knowledge,andskills.

Accepttheiranswersifanacceptablejustificationisprovided.4.4.2 Therearenorightorwronganswerstothisquestion.Itisthediscussionthatprovides

studentswithabetterunderstandingofwhatittakestobeasuccessfulearthscientist.4.4.3 Thefirsttaskwastoproposepossibletraits,knowledge,andskillsbasedongeneral

knowledge.Thesecondtaskinvolvedtakingthemajortraits,knowledge,andskillssuggestedandinvestigatingthembygatheringevidencefromthevideo.Thethirdtaskwastotesteachhypothesistoseeifitwasverifiedorjustifiedbyevidencecollectedfromthevideo.Iftherewasevidencetosupportthehypothesis,itcouldbeconsideredatheory;ifnot,itwouldberejectedanddisregarded.

4.4.4 Themostimportantaspectofthisanswerwouldbeasetofreasonsthatwereclearlyoutlinedandwereconsistentwiththestudent’sposition.

Chapter 5: Earthquake Hazard4.5.1 Studentsarelikelytosuggestareasofrecentearthquakesinthenewssuchas

southeastAsia,Japan,Peru,California,etc.4.5.2 ThisanswerwillvarywiththeirlocationinCanada.ItisexpectedthatB.C.residents

wouldperceiveahigherearthquakeriskandmagnitudethanallbutafewstudentsfromtheSt.LawrenceValley,wherethequakeriskmightbeconsideredmoderateandthemagnituderatherlow.

4.5.3 Reboundislinkedcloselytothetheoryofisostasy.Whenthetermreboundisusedbygeologists,itreferstoariseinablockofEarth’scrustthatoccurswhenaweightisremovedfromitstoporsurface.ExampleswouldbeariseinthecentreoftheCanadianShieldasaresultofthemeltingofthecontinentalglaciersthatoncecovereditor,inthecaseofthisvideo,theremovalofthehigherpartsoftheoriginalAppalachianMountainsbyerosionoverthepast350+millionyears.Earthquakeswouldresultasthesereboundingblocksofthecrustmoveupwardsalongsurroundingrocks.

4.5.4 Suchquakesareoftenminorinmagnitudeanddisplacement.4.5.5 Theyaremostcloselyrelatedtomountainbeltsalongplateboundaries.4.5.6 TheLoganLineorFault4.5.7 Tuttleislookingforevidenceinthesoilsoftheregionfor“sandblows”.Thesefeatures

occurwhenundergroundsandlayersareliquefiedduringamajorearthquakeandmoveupwardsthroughcracksinthesoilcausedbythequaketoformsandfountainsorblows.Byfindinganddatingthesefeatures,Tuttleisabletodatepastmajor

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earthquakesintheNewMadridareathousandsofyearsintothepast.Herresearchindicatesmajorearthquakesoccurapproximatelyevery500years.

4.5.8 StudentsarelikelytogettheimpressionthattheearthquakehazardineasternNorthAmericaisratherhigh.

4.5.9 Makecertainstudentslookatbothmapstodeterminethemagnitudeofquakesintheircommunityaswellasthehazardlevel.

4.5.10 ThiswilldependonyourlocationwithinCanada.4.5.11 Tobeacceptable,theanswermustbesupportedbyaccurateandrelevantevidence

andalogicalexplanation.Thereisnorightorwronganswertothequestion.

The Atlantic CoastChapter 1: Tales from the Ocean Floor5.1.2 TheTablelandsarealeftoverfragmentofancientoceanfloorthatpre-datesthe

modernAtlanticOcean.WhenwhatgeologistsnowcalltheLapetusOcean(“fatherofAtlantica”)openedup,theserockswerenewly-formedonthatancientseafloor.WhenPangaeawasassembling,theserockshadacollisionwithwhatisnowtheAfricancontinent,andthisoldoceanfloorwasweldedontothenewsupercontinent.WhenPangaeabrokeupandanewoceanemerged(theAtlanticOcean),thissliceofoldoceancrustwasferriedacrosstheglobetobecomeapartofeasternNorthAmerica.

ThevolcanicrocksfoundintheTablelandsareknowntobeabundantonlyincertainseafloorsettings.Tohavethemavailableabovesealevelgivesusachancetowalkacrossanancientpieceofoceanfloorandcontinuewalkingrightdowntotheuppermantle.

5.1.3 Themineralwaschromite,whichismadeupofabouttwo-thirdschromiumoxide(Cr2O3)andone-thirdironoxide(FeO).Itisaheavy,resistantmineralthatcommonlyformsinEarth’suppermantleanddeepcrust.FindingchromitecrystalsinthesedimentaryrocksatLobsterCovewasunexpected.

5.1.4 • Thepresenceofchromiteindicatedthattherocksofthisareawerenotconventionaligneousrocks,buthadthehallmarksofbeingformedverydeepintheEarth–morethan25kmsdeep–asfardownasEarth’suppermostmantle.PlatetectonicforcesplacedtheTablelandsinthelocationwhereitisfoundtoday,andisactuallytheremnantofanoceanfloorthatonceseparatedNorthAmericafromAfricaandEurope.ThenewinterpretationisthattheTablelandsdidnotformwhereitistoday,buthadbeenbroughtthereafterajourneyspanning400millionyearsandtheopeningoftwooceans!

• ThesequenceofrocksinthispartofGrosMorneNationalParkiswhatisknownasanophiolitesequence,whichisageologist’stermforasectionofrocksthatrepresentsthetop30kmsofanoceanfloorsetting.Ophiolitestendtohavelavaflowsattheirtops,wheretherockswereformedattheoceanfloorwheretheymetthewater.Deeperdown,thevolcanicrockstendtobemadeupofveryiron-richminerals,areheavyfortheirsize.SincetheophioliteatGrosMornewastipped

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upalmostverticallybytectonicforces,wecanliterallywalkfromthelavasoftheseafloorallthewayondowntotherocksoftheuppermantle.Imagineitasasliceoflayercakethathasfallenoveronitsside,andanantrunsacrossthelayers.WearethatantalongtheTablelands’trails.

5.1.5 ThefollowingWebsiteswillprovideinformationtocompletethisquestion:• This Dynamic Earth – the Story of Plate Tectonics http://pubs.usgs.gov/gip/dynamic/dynamic.html–Anintroductory-leveltreatmentofmostofthekeyideasandclassicalprinciplesoftheTheoryofPlateTectonics.ItalsoincludesalinktotheThisDynamicPlanetWebsitethatprovidesaweb-basedversionoftheinfluentialworldmapofglobaltectonics.

• Ophiolites http://volcano.und.nodak.edu/vwdocs/vw_hyperexchange/ophiolites.html–This

pagefromthepopularVolcanoworldWebsiteoutlineshowslicesofoceaniccrustcansometimesbethrustontothemarginsofcontinentsaslargeoceanbasinscloseupandcollisionofcrustalblocksoccurs.Itprovides“virtual”fieldtripstosomeoftheworld’smoreoutstandingexamplesofophiolites,includingthosefoundinOman,Cyprus,andNewfoundland.

• Gros Morne Adventures – Newfoundland Adventure Tourism http://www.grosmorneadventures.com/activities.html–Therelationshipsamong

geology,tourism,andtheactivelifestyleadvocatedtoday.

5.1.6 Sincethevolcanicrocksthatmakeupophiolitesareusuallybornatmid-oceanridges,itseemedsimpletoviewtheseslicesofoceanfloor/uppermantleasbeingpiecesof“fossil”spreadingcentres.Newermodelsactuallypointtoophiolitesformingatspreadingcentresveryclosetosubductionzones.Thismeansthattheyareleftstrandedwhenasliceoftheoceanfloorcollideswithacontinent.Studentsshouldfirstlookforareasoftheworldwherenewoceanfloorwilllikelybecreated,butquiteclosetoknownareaswheretheoceancrustislikelytobeconsumedataplateboundarythatisatrench.

ThemostlikelyplaceswherefutureophioliteswillbegeneratedwouldbealongthewestcoastofCanada(JuandeFucaplateboundary),thewestcoastofCentralAmerica,theRedSea/GulfofOman,andovermuchofthewesternmarginofthePacificPlate.

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5.1.7 Geology of the Tablelands, Gros Morne National Park, Newfoundland

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Chapter 2: Experiment in the Precambrian Oceans5.2.3 Thesefossilizedcreaturesrepresentaveryearlyexampleofwhathasbeencalled

“metazoan”lifeforms,meaningtheywerelarge,multi-cellular,andwouldbeeasilyvisibletotheeye.Priortotheirexistence,anypreviously-knownorganisms—suchasblue-greenalgaeandbacteria—weremicroscopicinsize.

Thebodyplansoftheseorganismshavenomodern-daycounterparts,nordidtheyexistmuchbeyondthebeginningoftheCambrianperiod.Thismakesthemasortof“niche”collectionthatisatypeof“experimentatlifegettingbig”asProfessorJimGehlingputsitinthisepisodeofGeologicJourney.

5.2.4 ThesefossilsoccurinrocksthatwereoncesittingrightnexttoAfricaandthenwere“brought”totheircurrentlocationaspartofa“geologicjourney”astheAtlanticOceanopenedupfollowingthebreakupofPangaea.Whenthefieldpartyreachedaparticularoutcroppingofthefossils,everyonewasaskedtoremovetheirfootwearinordertonotharmthesurfaceoftherocksthatcontainedtheimpressions.ThereareveryfewplacesintheworldwhereEdiacaran-ageanimalfossilsoccurinsuchabundance;MistakenPointisararefindforpaleontologists,andhasbeenvisitedbyinterestedpeoplefromaroundtheworld

5.2.5 Thediamondreferencespeakstosomethingasbeingrare,valuable,difficulttofind,occurringonlyinafewselectareasonEarth,beautifultotheeyeofthebeholder.ThesethoughtscanthenbemadeanalogoustothefossilsatMistakenPoint,whichareimpressionsofrareanimals,holdgreatsignificancetothegeologichistoryofEarth,andalsohaveacertainbeautyaboutthemamongthosepeoplewhoappreciatetheirexistenceandimportance.

5.2.6 • AccordingtotherecreationsseeninGeologicJourney,theseanimalswere“sessile”,ie.attachedtotheseabottombyasortofholdfast,oranchor,structure.Themannerinwhichtheydiedsuggeststhatsmall,localized“gardens”ofEdicarananimalslivedincloseproximitytooneanother.Sincenonehadjaws,teeth,mobility,oradigestivesystemandwereallfilterfeeders,predationwaslikelynotoccurringatall.Theseanimalslivedalongashallow-waterslopeadjacenttoanoceanshoreline,butsincetheyarepreservedamongshales(arocktypecharacteristicofdepthsbelowwheresunlightpenetrates),itseemsthattheylivedincompletedarknessallthetime.

• TheMistakenPointcollectioniscappedontopbyathicklayerof“tuff”(hardenedvolcanicash).Thisindicatesthatthisparticularlocationwasonceunderthedirectinfluenceofactivevolcanoes.Thoughtheeruptionitselfwouldnothavebeenfataltothem,thevolcanicashrainingdownontheseawouldhavedriftedtothebottomandcoveredthem.

5.2.7 TheWardfamily,livingclosetothefossilbeds,recognizethattheyhaveanimportantvolunteerroleinassistinginthepreservationofthisuniquesite.Oneparticularanimalspeciesamongthecollectionbearsthefamilyname,andwasfirstdiscoveredbyMrs.Ward’sson.

5.2.8 HumansconstitutetheonlyknowntechnologicalspeciesinEarthhistory.Weactuallyhavetheabilitytoeliminateourselvesratherthanbeextinguishedbymorenaturalmeans.Itwouldbeinterestingtodiscover–fromstudents’views–whetherthismakesusaparticularlyfragilespeciesthatisperhapsthemostuniqueexperimentyetinlifeonEarth.

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5.2.9 Concept Map: Mistaken Point Fossils

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Chapter 3: Mass Extinction….and Something New Out of Africa5.3.1–5.3.4 Researchingscientificinformationforaprojectinvolvesdifferentskills,thinking,

andkeywordapproachesthanlookingupamovietrailer,afavouritemusician,orsports-relatedinformation.

Usingavarietyofsearchenginesthatstudentscanidentifyandhaveused(Yahoo,Infoseek,Google,Dogpile,Yahooligans,AskJeeves,AltaVista,RagingSearch,etc.),havestudentssearch“massextinctions”,oranyothertopicrelatingtoanepisodeofGeologicJourney.Recordresultsoffindingsforeachsearchengineonaclasschartortable,notingthekeywordsearchterm(s),thenumberofhitsobtained,theorganizationofhits(e.g.,groupedbysearchenginetype,ratingsinpercentages,etc.)

Dotheresultsobtainedbyeachstudentmatchtheiroriginalpredictions?Howdotheresultscomparefordifferentsearchengines?Discusspossiblereasonsforthedifferencesbetweentheirpredictionsandactualresults,andbetweenthedifferentsearchengines.

Answerswillvary,butcharacteristicssuchastheeasilyvisiblesedimentarycharacteroftherocks(clearbedding),theabundanceoffossils,actionofthelocaltides,heightofthecliffs,shouldemerge.

5.3.6 EldonGeorgehasknowntheareasincehewasachild,andhiskeeninterestinrocks,mineralsandfossilsstemsfromhishavingincurredanarminjurythatdidnothealcompletely.Thiskepthimawayfromtheactivitiesmostofthelocalboysengagedinwhilehewasyoung.Hehasbeencollectingfordecades,andhashadthetimetospendovertheyearswiththisfossil-richarea.Eldonhasparticularknowledgeofthecrocodile-likeorganisms,andrecognizesthedinosaurfootprintswithaneyeasgoodasthatofanypalaeontologist.PerhapsthegreatestcontributionhemakesisthroughdiscussionswithvisitorstotheareapromotingtheimportanceofunderstandingancientlifeonEarth.

5.3.7 Thegeologicandscientificinterestiswiththeageoftherocksthatcontainthefossils.OnemajorextinctionepisodeoccurredatthetransitionfromtheTriassictotheJurassicperiods.ParrsboroBeachhasrocksthatdatepreciselytothistimeboundary.Therefore,the“richtreasure”isallaboutunderstandingwhatsortsofanimalsdidanddidn’tsurvivetheextinctionevent.TheParrsbororockscontainthefossilremainsoftheanimalsthatrepopulatedtheplanetfollowingtheextinctionthateliminatedmorethanhalfoftheworld’sspecies(accordingtothefossilevidence).Thesmall,mammal-sizedreptilesfoundatParrsboroweretheprecursorstothegreatgiantreptilesthat“ruled”thepredatorworldintheJurassicPeriodthatfollowedsometimelater.

5.3.8 Dr.PaulOlsenandDr.JessicaWhitesidearetestinganideathatthereisaconnectionamongsuper-continentbreakup(Pangaeainthisinstance),volcanicactivity,andlarge-scaleextinctionevents.Theriftingapartoflargeblocksofcrustisaccompaniedby,orperhapsevendrivenby,significantperiodsofigneous(volcanic)activity.Theincreasedvolcanismmaythencausedramaticclimaticdisruptionwhichleavesvulnerableorganismsatriskduetolossofhabitat,scarcityoffood,lowerlevelsofsunlight,andevenglobalcooling.TheirrecentworkhasbeenunabletoestablishaclearconnectionbetweenthevolcanicoutpouringsintheNorthAtlanticregionattheendoftheTriassicPeriodandthetimingoftheextinctionevent.Moreworkneedsto

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bedonetotestthishypothesis.Dr.Whitesideusestheratiooftwostableisotopes(meaningnon-radioactive)ofcarbon–carbon-13andcarbon-12–asameansofdeterminingthetypeofatmosphericenvironmentthatorganismslivedinlongago.

Weusecarbonisotopedataforexactlythesamereasonthatweuseoxygenisotopedata–tofindoutfromwheretheatomsinaspecificobject(e.g.,ananimalorplant)arederivedandwhattheirhistoryhasbeen.Thehistoryofcarbonatomsinlivingorganismsinvolveshowtheorganismsobtainedthesecarbonatoms.Forplantsthismeanshowtheirphotosyntheticreactionsworked;foranimals,whattheyhavebeeneating.Carbonisotopicrecordsincarbonaterocksareofinteresttopaleo-ecologistsbecausetheyhelpunderstandthefunctioningofthecarboncycleduringearthhistory,andthroughthecarboncycle,thehistoryofthebiosphere.

WhatDr.Whitesideishopingtoderivefromthecarbonisotope“fingerprints”inthecarbonaterocksandfossilsoftheAtlasMountains(asseeninGeologicJourney)iswhetherthereisanyevidenceofadeviationfrom“normal”photosynthesisinplants,orsomesortofabigdisruptionintheglobalcarboncycle.Disruptionsinthecarboncyclecouldbeasignalofsomesortofglobalcatastrophethatwouldexplainthemassextinctionevent.

5.3.9 Humanity’sincreasingpopulationanddemandfornaturalresourcesmakesuspotentiallyanunsustainable,almostpredatory,speciesonthisplanet.ByvirtueofthelargeamountsofCO2weproducethroughburningfossilfuels,humansmayeventuallybecontributorstochangesintheworld’scarboncycling.ThatmakesusapotentialgeologicalforcethatcouldendupcontributingtoyetanotherlargeextinctioneventonplanetEarth.

5.3.11OnlineinformationabouttheendTriassicextinctionevent(especiallyteacherbackgroundorformotivatedstudents)canbefoundat:

• www.uky.edu/KGS/education/EndTriassic.htm

• en.wikipedia.org/wiki/Triassic-Jurassic_extinction_event

• palaeo.gly.bris.ac.uk/Palaeofiles/Triassic/triextict.htm

• www.space.com/scienceastronomy/planetearth/jersey_dinosaurs_020516-1.html

• www.space.com/scienceastronomy/planetearth/extinction_permian_000907.html