Geoheritage Pamphlet 2010.Cdr
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Department of OttawaGeologicalHistory EarthSciences (http://www.geoscape.nrcan.gc.ca/ottawa/index_e.php) TheoldestrocksintheregionarethePrecambrian metamorphicrocks,(mainlymarble,gneissandquartzite)and igneousintrusions,(includinggraniteandpegmatite)ofthe ExploreGeoheritageDay GatineauHillsandsomesmallareasofCarpandKanata. Theserocksarethedeeplyerodedrootsofancientmountains Sunday,October24,2010 thatwereonceastallasthepresent-dayHimalayas.Between 1.2and1.0billionyearsago,sedimentaryandvolcanicrocks, 10:00amto3:00pm* originallydepositedalongthemarginofancientNorth America, weredeformed,metamorphosed,andintrudedbymagmaasa resultofcollisionwithanothercontinent. Thiscollisionceased Comejoinourvolunteersfrom about1billionyearsagoandthemountainsbegantobeslowly erodedandwornaway.Duringthefollowing~100million CarletonUniversity’sDepartment years,wehavenorockrecord,probablybecauserockwas ofEarthSciencesandthe beingremovedbyerosionratherthanbeingdeposited. OttawaGatineauGeoheritage InthePaleozoic,between510and440millionyearsago,a warmtropicalseafloodedtheregion.(Wewerenearthe Projectatareaparks,heritage equatorthen!) TheoldestPaleozoicrockfoundintheareais sitesandgreenspacesandlearn Cambrianinage,(theNepeansandstone)andrepresentsan ancientbeach.IntheOrdovician,anoceanmovedonshore howgeologicalprocesseshave andcoveredthisbeachsothatlimestone(reefs)andshale (deepseasediment)weredepositedontopofthesandstones. shapedthelocallandscapeand Thisoceanadvancedandretreatedcreatingathicklayerof providedresourcesforouruse. sedimentaryrock.Fossilremainsoftrilobites,cephalopods, crinoids,corals,snails,andothershelledanimalsthatlivedin Inthelast2billionyears theancientcoralreefscanbefoundbythethousandsinthe theOttawaValleyhas shaleandlimestonelayersinthearea. ChamplainLookout,Gatineau Thereisnorecordofwhathappenedinthefollowing~400 beenahugemountain ChamplainBridgeStromatolites millionyears,asthereisnolocalrockofthisagerange. Perhapsnorockwasdeposited,orperhapsitwas,andthen chain,atropicalbeach, BrebeufPark,Gatineau waserodedaway. habitatforlargewhales, OttawaBuildingStoneWalkingTour About175millionyearsago,intheMesozoic,theOttawa- HogsBackPark,Ottawa Bonnecheregrabenformedwhenthelandsurfacedropped andburiedunder2kmof BillingsEstate,Ottawa, RandyBosswell downwardbetweenthetwomajorfaultzoneswhichformthe boundariesoftheOttawaValley. Theseancientfaultshave ice...Wheredotherocks and fossilactivities beenreactivatedovertime,andareoccasionallyactivetoday, inyourbackyardfitin? CarpRidgeHike,Kanata releasingcrustalstressintheformofearthquakes. ErskineJohnstonPublicSchool,Kanata DuringtheQuaternary,greaticesheets,sometimes2kmthick advancedandretreatedseveraltimesoverthenorthernhalfof MerBleueBog,Orleans North America,finallyretreating~12,000yearsago . Theloose sedimentsthatblanketbedrockinmuchoftheOttawa- Gatineauareawereleftbehindastheseglaciersmeltedatthe endoftheIce Age. http://www.geoscape.nrcan.gc.ca/ottawa/index_e.php *unlessotherwisenoted DowntownOttawaBuildingStone ChamplainLookout,GatineauPark, BillingsEstate,Ottawa (*opens11:00am) WalkingTour (*begins10:30am) Quebec On Riverside Drive turn onto Pleasant Park Drive, and ThebuildingsofOttawa'sdowntowncoreprovidea right again at Cabot, following the signs to the FromOttawa,driveacrossChamplainBridge,right museum at the end of the road. Jounalist Randy fascinatinglookatstonefromquarriesinOntario, onto Alexandre TachéandleftontoPromenadedela Boswell will speak about Elkanah Billings, the first Quebec,ManitobaandtheeasternUS.Wewill GatineauParkwayintoGatineauPark.Followthesigns Paleontologist with the Geological Survey of Canada, beginatParliamentHill’sCentennialFlameat and his contribution to our knowledge of ancient life. toChamplainLookout~20kmfrom Alexandre Taché. You will also find a display of some of the 1000 new 10:30am.SiteswillalsoincludetheNationalWar Theretainingwallofthelookoutisbuiltfrom species of fossils described by Elkanah including the Memorial,ConfederationSquare,CityHalland Precambrianrockscommonintheparkandthe unique and important Ediacaran fauna from LisgarCollegiate. Newfoundland. You will also find volunteers who will ChamplainBridgeStromatolites, informationplaquesprovideanoverviewofthe help you to make “fossil” impressions to take home geologicalhistoryoftheNationalCapital Area. and learn the special conditions under which fossils Gatineau,Quebec Volunteerswillbeonhandtotalkabouttheregional are preserved and found. FromOttawa,driveacrossChamplainBridgeand geologythathasshapedthelandscapeasseenfrom W.ErskineJohnstonPublic turnleftatthefirststoplightsontheGatineauside thislocation,aswellasthegeologicalhistoryof School,Kanata oftheBridge.FollowRueLucerneabout100mfrom GatineauPark. DrivewestonQueensway/417pastMoodieDrive. thelights,andturnleftagainintoSamuelde HogsBackPark,Ottawa TakeMarchRd.exittoKanata. Atlights,continue Champlainparkinglot.Walkafewstepsriverwardto HogsBackParkislocatedonthenorthsideofHogs straightontoCampeauDr.,turningrighton Teron thebikepath. Turnleftonthispavedpathandwalk Rd.,leftonBeaverbrook,thenrightonVarleyDr. BackDrivebetweenRiversideandColonelByDrive. FollowthiscurvingroadtoW.ErskineJohnston halfwaybacktowardChamplainBridge. Alongthe FromCarleton'scampuswalksouthalongthecanalfor PublicSchool.Parkinaspotneartheplayground river,youwillseeapavementofcircular,mounded 10minutesuntilyoureachHog'sBackRoad. Thefalls structures. Therocksintheschool’sbackyardare structurescalledstromatolites,formed 450million mainlymetamorphicrockswithsomeigneous areontheleft. TheserocksarefromtheCambrianand intrusions. TheyarepartoftheGrenvilleProvince yearsagoduringtheOrdovicianEra, whenmatsof OrdovicianErasandwereformedinatropicalshallow oftheCanadianShield,andaremorethan1billion cyanobacterialivinginshallowwarmwaterbuilt waterenvironment. Youcanseefossils,glacialstriae, yearsold. Thesebasementrocksareamongthe domedstructuresbytrappingsedimentgrainsinto oldestintheNationalCapital Area,andarea sedimentarystructuresandalsohowrockscanbe beautifulexampleofhowrockscanbefoldedand layers.StromatoliteswerecommonintheEarly foldedandbrokenupbyfaults. deformedinsideamountainbelt. Therounded Paleozoicastherewerenosnailstoeatthealgae; CarpRidgeHike,Morgan’s shapesoftheoutcropsandthegroovesonsurfaces nowstromatolitesonly forminveryrestricted (*begins12noon) aretheresultofglaciersmovingoverthesurface Grant,Kanata duringthelastIce Age. environments,themostfamousbeinginSharkBay, TakeHWY 417toMarchRoadnorth,andturnleftonto Australiawherethewateristoosaltyforsnailsor KlondikeRoad.Followthisroadtotheendandpark MerBleueBog,Orleans otheralgaepredatorstosurvive. 12 Take the 417 east to Innes Road exit, turning left/east onSecondLineRoad. Thehikewillstarthereat towards Orleans. Turn right on Anderson Road and BrebeufPark,Gatineau,Quebec noon. Thetrailwilltakeyouovermetamorphicand continue south on Anderson to the top of the second Frompreviousstop,turnrightontoRueLucerneand igneousrocksofthePrecambrianGrenvilleProvinceof hill; turn left onto Ridge Road. At the end you will find the board walk interpretive trail. This important turnrightatRueBegin.Gototheendofthestreet. theCanadianShieldandtheoverlyingPaleozoic ThemonumentrepresentsJesuitmartyrBrebeuf. wetland is a remnant of the Champlain Sea formed NepeanSandstone. Theserockshavebeenexposed during the retreat of Glaciers some 9500 years ago. Parkinadesignatedareaandwalkdowntothe byfaultingalongthesouthernmarginoftheOttawa This type of ecosystem is commonly found in the boreal forests of northern Canada. river.Ordovicianlimestoneiswellexposedalong BonnechereGrabensystem. theshorelinewithabundantcorals,cephalopods, The new website for the Ottawa Gatineau Geoheritage Project will be coming on- gastropods,mollusks,brachiopods,bryozoa,trace line in November. Tolearn more about the Project and find more information about Formoreinformationvisitwww.earthsci.carleton.ca interesting geological sites in the National Capital area, fossilsandfragmentsoftrilobites.* googleOttawa Gatineau Geoheritage Project in November!.