Plate Tectonics Exercise - geode | Google Earth for Onsite...
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Plate Tectonics Exercise Step 1: On your PC or laptop go to the web URL below: http://geode.net/pangaeaBreakup/ You should see the following webpage: Click the upper blue button to download the Pangaea Breakup KML file to use the animation in the Google Earth application (which needs to be installed on your computer). To download Google Earth for your computer, go here: https://www.google.com/earth/download/ge/agree.html Once you have everything installed and have opened the Pangaea Breakup.kml file in Google Earth, a virtual globe rendering of the supercontinent Pangaea (like the image to the right) should appear after a few minutes (this may take longer on an off-campus computer.)
Transcript of Plate Tectonics Exercise - geode | Google Earth for Onsite...
PlateTectonicsExercise Step1:OnyourPCorlaptopgotothewebURLbelow:
http://geode.net/pangaeaBreakup/
Youshouldseethefollowingwebpage:
ClicktheupperbluebuttontodownloadthePangaeaBreakupKMLfiletousetheanimationintheGoogleEarthapplication(whichneedstobeinstalledonyourcomputer).TodownloadGoogleEarthforyourcomputer,gohere:https://www.google.com/earth/download/ge/agree.htmlOnceyouhaveeverythinginstalledandhaveopenedthePangaeaBreakup.kmlfileinGoogleEarth,avirtualgloberenderingofthesupercontinentPangaea(liketheimagetotheright)shouldappearafterafewminutes(thismaytakelongeronanoff-campuscomputer.)
Step2:Atthispointyoushouldseesomethingliketheimageatthebottomofthepreviouspage.ThisisavirtualglobeanimationofthesupercontinentPangaeaanditssubsequentbreakupspanningthetimeperiodfrom200Ma(millionyearsago)tothepresent.SpendthenextseveralminutesexploringthevariousaspectsofthePangaeaBreakupinteractiveanimation.
Thingstonote:- OntheleftsideoftheGoogleEarthwindow,youwillseea“Places”
windowthathasthePangaeaBreakupfolderlistunderthe“TemporaryPlaces”folder.YouwillusetheselectionboxesforthefolderslistedunderthePangaeaBreakupheadingtocontrolwhatisshowninthemainGoogleEarthwindow
- Underneaththe“Places”windowyouwillseea“Layers”window.Makesuretodeselect(turnoff)the“PrimaryDatabase”,whichshouldbethetopitemintheLayerswindow
- NowlookingatthemainGoogleEarthwindow(thatshowsthevirtualglobe),youcanrotatethevirtualglobetoanydesiredviewpointbyclickingontheglobeandmovingyourmousewhileholdingdownthemousebutton
- ThetimeperiodinMa(millionsofyearsago)forthecurrently-displayedarrangementofcontinentsisshowninyellowattheupperrightofthescreen
- Intheupperrightcornerisaverticalscalebarthatyoucandragupanddowntozoominandoutofspecificlocations
- Youcanchangethegeologictimeperiodshownbyslidingthewhitetabonthebluebaratthetopleftcornerofthewindow
- Inthe“View”dropdownmenuatthetopofthescreenyoucantogglealatitudeandlongitudegridbyclicking“Grid”
- Continentscanbeselectedanddeselectedviacheckboxesbyeachcontinentnameinthe“Places”window
- Otherfeatures,suchasMountainBelts,HotSpots,FossilDistribution,etc.canbeshownusingthecheckboxesinthe“Features”menu
- ExploreautomatedanimationsofthebreakupofPangaeafromvariousviewpointsbyselectingalocationinthe“Tours”menu
OnceyouhavefamiliarizedyourselfwiththePangaeaBreakupinteractiveanimation,proceedwiththeexercisethatfollows.
Name(s) Date
PlateTectonicsExercise
Background–PlatetectonicsdescribestheEarth’scrustasbeingarigidexterior,whichisdividedintoseveralslabs,or“plates”,whicharelocatedabovetheconvectingmantleandmovethroughtime.DissipationofheatfromtheEarth’sinteriordrivesplatemovement.Theboundariesbetweenplatescanbeconvergent(collisional),divergent(extensional),orside-to-sidemovement(strike-sliportransformmovement)andtypicallyfeaturemountainranges.ThetheoryofplatetectonicswasinfluencedbyAlfredWegener’shypothesisofcontinentaldrift,introducedin1915.Wegenersuggestedthattherewasonceasinglelandmass,orsupercontinent,thathereferredtoas“Pangaea.”SomeoftheevidencethatWegenerusedincluded:theapparentjigsawfitofthecontinents,fossilevidence,evidenceofpastglaciations,andthecorrelationofancientmountainbeltsacrosscontinents.Wewillexplorethisevidenceforplatemovementinthisexercise.UsethePangaeaBreakupmodeltoanswerthefollowingquestions.JigsawfitoftheContinents–ThePangaeaBreakupmodelshowsthemovementoftectonicplatesoverthelast200millionyears.Itshows,indetail,themovementofplatesthatWegenerproposedin1915.Exploreplatemovement/continentaldriftbyansweringthequestionsbelow.1.WhenPangaeawasstillasupercontinent(200Ma),whichpresent-daycontinentwaspartiallylocatedattheNorthPole(HINT:TurnonGrid)?
a. Antarcticab. Australiac. Eurasiad. NorthAmerica
2.Approximatelyhowmanymillionsofyearsago(Ma)didpresent-dayIndiabreakawayfrompresentdayMadagascar?
a. 20Mab. 50Mac. 80Mad. 120Ma
3.From90Matothepresent,whichcontinent/landmasstravelledthegreatestdistance(HINT:TurnonGridandestimatedegreesoflatitudeorlongitude)?
a. Africab. Indiac. NorthAmericad. SouthAmerica
4.Intermsofitsgeographiclocation,whichmoderndaycontinentisclosesttowhereitwasat200Ma?
a. NorthAmericab. SouthAmericac. Antarcticad. Australia
MountainBelts–Thecorrelationofancientmountainbeltsacrossnowseparatedcontinentswasanotherpieceofevidencethatsupportedtheideaofcontinentaldrift.Select“MountainBelts”andexplorethisideabyansweringthequestionsbelow.5.WhichmountainbeltswereadjacenttoeachotherpriortothebreakupofPangaea(HINT:Zoominorclickonthegreenmountainsymbols)?
a. CascadeandMauritanian(westernAfrica)mountainsb. Ouachita(SENorthAmerica)andGreenlandmountainsc. GreenlandandCaledonian(westernEurope)mountainsd. MauritanianandSierraNevadamountains
6.Whatmountainbeltsonnow-separatedcontinentswerelikelyconnectedasasinglemountainbeltonthesupercontinentofPangaea?
a. TheAndesandtheRockiesb. TheAlpsandtheAtlas(Africa)Mountainsc. TheSredinnyRange(easternAsia)andtheSierraNevadaMountainsd. TheAustralianAlpsandtheTransantarcticMountains
7.AsectionoftheSouthernAppalachianMountainsarelocatedinVirginia(Select“Virginia”).WhichmountainbeltwasnexttotheVirginiaAppalachiansat200Ma?
a. TheAtlasMountainsb. TheCaledonianMountainsc. TheGreenlandMountainsd. TheMauritanianMountains
FossilEvidence–Thepresenceofthesamefossilspeciesinnowseparatedcontinentsisfurtherevidenceforcontinentaldrift.Select“Fossildistribution”toexplorethisideainthequestionsbelow.8.WhichfossilsarefoundinSouthernAfrica(HINT:Zoominorclickonthefossilsymbols)?
a. Cynognathusb. Lystrosaurusc. Mesosaurusd. Alloftheabove
9.Glossopterisisanancientfern-likefossilfoundonAntarctica.Whereelsecanthisfossilbefound?
a. Indiab. Australiac. SouthernAfricad. Alloftheabove
10.Mesosaurusisafresh-waterreptilefossilfoundoncontinentsinthesouthernhemisphere.Basedonthelocationsofthesefossils,whichcontinentswithMesosaurusfossilswerelikelyadjacenttoeachother?
a. AntarcticaandIndiab. AfricaandSouthAmericac. AustraliaandIndiad. NorthAmericaandEurope
GlacialEvidence–Paleozoicglaciationsthatcanbefoundatlocationsonseveralcontinentsareevidencethatthecontinentswereonceconnected.Select“Paleozoicglaciation”andexplorethisideabyansweringthequestionsbelow.11.WhichmoderndaycontinentdoesnotshowevidenceofPaleozoicglaciation?
a. Australiab. Africac. NorthAmericad. SouthAmerica
12.Glacialevidencelocatedneartheequatortodaysuggeststhatthosecontinentswereoncelocatedincolderregionsnearthepoles.Whichcontinentshaveglacialevidenceneartheequatortoday?
a. AustraliaandAntarcticab. AfricaandSouthAmericac. NorthAmericaandEurasiad. Alloftheabove
ModernPlateTectonicsPlateBoundaries–Thereare3basictypesofplateboundaries:Convergent–Whenplatescometogether.Oneplatewillbesubductedundertheother.Thisformsfeaturessuchasmountains,islandarcsystems,andoceantrenches.Divergent–Whenplatesmoveapart.Thiscreatesspreadingcentersthatshowupasseafloorspreadingzonesinoceaniccrust,andriftvalleysincontinentalcrust.Transform–Whenplatesslidepasteachother.Theyareverycommoninoceanswheretheyoffsetmid-oceanridges.TheycanalsoformplateboundariesliketheSanAndreasFaultinCalifornia.Select“Presentplateboundaries”andexploreplateboundariesbyansweringthequestionsbelow.Makesurethetimesliderissettothepresentday(0Ma).13.WhattypeofboundaryisfoundbetweentheSouthAmericanPlateandtheNazcaPlate?
a. Convergentb. Divergentc. Transformd. Undefined
14.WhatisthemainplateboundarytypefoundattheMid-AtlanticRidge?
a. Convergentb. Divergentc. Transformd. Undefined
15.Whattypeofpresent-daycollisionformedtheHimalayanMountainsattheboundarybetweentheIndianPlateandtheEurasianPlate?
a. Continent-continentcollisionb. Continent-oceancollisionc. Ocean-oceancollisiond. Undefined
16.Whattypeofpresent-daycollisionformedtheCaribbeanIslandsalongtheeasternboundaryoftheCaribbeanPlateandtheNorth/SouthAmericanPlates(HINT:deselectBlueBackgroundtoseetheCaribbeanIslands)?
a. Continent-continentcollisionb. Continent-oceancollisionc. Ocean-oceancollisiond. Undefined
17.Whereistheoldestoceancrust(oceanlithosphere)located(HINT:Select“Oceanlithosphereage”andlookforthepurplecoloredbands)?
a. ArcticOceanb. IndianOceanc. SouthernAtlanticOcean(belowtheequator)d. WesternPacificOcean(neartheAntimeridian)
Hotspots–Columnsofrisingmoltenmaterialfromdeepinthemantle,knownas“mantleplumes,”risetothesurfacewheretheenergyisreleasedvia“hotspot”volcanoes.Whenlong-livedmantleplumesencounteroceaniccrusttheycreatehotspotchains,duetothemovementofatectonicplateoverarelativelystationaryhotspot.AnexampleofthisistheHawaiianIslandchain.Whenmantleplumesencountercontinentalcrusttheycreatevolcaniccalderas,suchastheYellowstoneCaldera.Select“HotSpotVolcanos”andexplorehotspotsbyansweringthequestionsbelow.18.Whatistheageoftheoldestseamount(DetroitSeamount)intheHawaiianIslandchain(HINT:RunthetimesliderbackwardsuntiltheDetroitseamountisatthelocationoftheHawaiianmantleplume)?
a. 6Mab. 34Mac. 39Mad. 78Ma
19.WhatistheoldestvolcanicfeatureintheYellowstoneHotspotchain?
a. YellowstoneCalderab. WalcottTuffc. MesaFallsTuffd. McDermittCaldera
20.TheNinetyEastRidgehotspots(intheIndianOcean)initiatedwiththeKerguelenfloodbasaltplateaus(outlinedwithredpolygons)thateventuallyincludedBrokenRidge.WhendidthefirstKerguelenplateausstarttoform?
a. ~50Mab. ~80Mac. ~110Mad. ~140Ma
SelectedReferencesBird,P.,2003,Anupdateddigitalmodelofplateboundaries,Geochemistry,Geophysics,Geosystems,vol.4,1027,doi:10.1029/2001GC000252.Müller,R.D.,Roest,W.R.,Royer,J.-Y.,Gahagan,L.M.,Sclater,J.G.,1997,Digitalisochronsoftheworld'soceanfloor,JournalofGeophysicalResearch,vol.102,p.3211–3214.Müller,R.D.,Sdrolias,M.,Gaina,C.andRoest,W.R.,2008,Agespreadingratesandspreadingasymmetryoftheworld'soceancrust,Geochemistry,Geophysics,Geosystems,vol.9,Q04006,doi:10.1029/2007GC001743.Torsvik,T.H.,Steinberger,B.,Gurnis,M.andGaina,C.,2010,Platetectonicsandnetlithosphererotationoverthepast150My,EarthandPlanetaryScienceLetters,vol.291,p.106-112,doi:10.1016/j.epsl.2009.12.055.
