Produce a module summary on Canadian Shield region. This summary should highlight the major processes and landforms found in each region, and can be used as a review tool for the final exam. This sum

Page%|%1%%%MODULE'5:'CANADIAN'SHIELD'UNIT'1:'GEOLOGY'AND'TOPOGRAPHY'Slide%1:%Welcome%back%to%GEOG%3760%Canada’s%Natural%Environments%and%Landforms.%%I%hope%you%had%a%pleasurable%and%relaxing%break!%%In%this%fifth%module%of%the%course,%we%are%going%to%move%east%and%discuss%the%features%of%the%Canadian%Shield%physiographic%region.%%As%with%all%modules%we%will%begin%this%unit%by%discussing%the%geology%and%topography%found%within%this%region.%%%Slide%2:%The%Canadian%Shield%encompasses%most%of%central%and%eastern%Canada,%including%parts%of%the%Northwest%Territories%and%Nunavut,%northern%Alberta,%Saskatchewan%and%Manitoba,%most%of%Ontario%and%Quebec,%as%well%as%Labrador.%%The%pink%area%on%the%map%of%the%physiographic%regions%represents%the%spatial%extent%of%the%Canadian%Shield%region.%This%region%is%also%known%as%the%Precambrian%Shield%or%Laurentian%Plateau.%%%%Slide%3:%In%Canada,%the%Canadian%Shield%covers%approximately%50%%of%the%land%mass%or%over%4.8%million%square%kilometers.%%Like%some%of%the%other%physiographic%regions%we%are%discussing%in%this%class,%this%region%is%not%solely%restricted%to%Canada,%but%extends%southward%into%the%northern%United%States.%%The%Adirondack%Mountains%of%New%York%state,%as%well%as%the%northern%sections%of%Michigan,%Wisconsin%and%Minnesota%are%also%part%of%the%Canadian%Shield.%%%Most%of%Greenland%is%also%composed%of%Canadian%Shield%rocks.%%Including%the%United%States%and%Greenland,%the%Canadian%Shield%covers%almost%8%million%square%kilometers.%As%you%may%have%noticed%in%the%previous%slide,%this%region%has%a%UZshaped%or%horseZshoe%pattern,%centered%on%Hudson%Bay.%%In%terms%of%elevation,%it%is%also%saucerZshaped,%resembling%a%soup%plate.%%On%the%south,%east%and%north%sides,%the%land%of%the%Canadian%Shield%is%elevated%reaching%over%600%meters.%%In%the%northeastern%section%(i.e.%in%northern%Labrador),%the%Earth’s%crust%rises%to%elevations%greater%than%1500%meters.%%This%creates%a%rim%(similar%to%a%rim%on%a%soup%plate).%%%%%%Slide%4:%The%Canadian%Shield%is%part%of%an%ancient%continent%known%as%Arctica.%%This%supercontinent%was%formed%approximately%2.5%billion%years%ago%during%the%Neoarchean%era.%%Over%time%(due%to%the%process%of%plate%tectonics%and%continental%drift)%Arctica%broke%up%into%what%is%now%called%North%America,%Greenland,%Scotland,%Siberia%and%Antarctica.%%In%the%supplementary%information%for%this%unit,%I%have%included%more%information%on%this%supercontinent.%%%%% Page%|%2%%%Slide%5:%This%region%is%the%oldest%part%of%the%North%American%plate,%over%2%billion%years%ago.%%It%was%also%the%first%part%of%North%America%to%be%permanently%raised%above%sea%level.%%How%do%we%know%this?%%We%can%determine%the%age%of%the%Canadian%Shield%by%dating%bacteria%and%algae%fossils%present%in%the%rock.%%This%age%compared%to%similar%dating%methods%in%the%other%physiographic%regions%draws%us%to%the%conclusion%that%it%must%have%been%the%first%region%of%the%North%American%craton%to%be%exposed.%%A%craton%is%a%large%stable%section%of%the%Earth’s%crust%forming%the%center%of%the%North%American%continent.%%Since%that%time,%the%Canadian%Shield%has%undergone%a%number%of%different%tectonic%forces%(for%instance%folding%and%faulting)%and%weathering%processes%(such%as%glacial%and%fluvial%erosion%and%deposition)%that%have%not%only%changed%the%initial%environment,%but%also%created%the%features%we%will%discuss%further%on%in%this%unit%and%module.%During%the%last%few%million%years,%this%region%is%relatively%stable%with%little%tectonic%forces%due%to%plate%tectonics.%The%rocks%that%make%up%the%base%of%this%region%are%mostly%metamorphic%in%type%and%were%formed%during%Precambrian%Era%and%dated%between%4.5%billion%and%540%million%years%ago.%%These%rocks%also%have%a%characteristic%crystal%structure.%%At%the%microscopic%level,%the%atoms%or%molecules%are%arranged%in%an%ordered%pattern%in%all%three%dimensions.%%This%gives%the%rocks%a%very%homogenous%appearance.%%The%high%pressure%and%temperature%at%the%time%of%formation%(due%to%the%fact%that%they%were%produced%in%a%young%Earth%environment%with%numerous%volcanic%activity%occurring)%has%resulted%in%this%structure%and%type.%%It%has%also%resulted%in%substantial%deposits%of%various%minerals,%which%will%be%discussed%in%the%last%unit%of%this%module.%%Slide%6:%The%Canadian%Shield%can%be%divided%into%five%smaller%physiographic%provinces.%%The%first%one%we%will%discuss%is%the%Laurentian%Upland.%%This%province%is%located%in%the%southern%portion%of%the%shield%in%the%province%of%Quebec%(as%shown%on%the%figure%on%this%slide)%and%extents%from%the%Laurentian%Mountains%in%the%west%into%the%Ontario%Valley%and%the%Opeongo%Hills%in%the%east.%%The%Laurentian%Upland%is%composed%primarily%of%Precambrian%igneous,%sedimentary%and%metamorophic%rocks%that%are%1%to%1.7%billion%years%old.%%These%rocks%have%been%faulted%and%uplifted%and%over%time%have%undergone%significant%erosion.%%These%processes%have%resulted%in%rolling%or%mountainous%peneplain%that%covers%most%of%this%province.%%A%peneplain%is%a%gently%undulating%plain%that%has%been%produced%primarily%by%fluvial%erosion%during%extensive%periods%of%tectonic%stability.%%A%number%of%hills%are%located%in%this%region%(including%Mont%Sir%Wilfrid,%Mont%Tremblant%and%Mont%SainteZAnne)%with%elevations%in%excess%of%1000%meters.%%The%remaining%area%is%river%valley%or%basins%formed%by%lake%processes%(or%lacustrine%basins).%%%% Page%|%3%%%Slide%7:%The%second%physiographic%province%that%makes%up%the%Canadian%Shield%is%the%Davis%Highland.%%The%location%of%this%province%is%shown%in%the%figure%on%this%slide%and%is%found%in%the%Arctic%region%and%Labrador.%%High%plateaus%with%an%elevation%of%over%700%meters%characterize%the%Davis%Highlands.%%Igneous%and%metamorphic%rocks%make%up%this%province.%%The%plateau%has%been%incised%by%northeastZtrending%fjords%and%valleys,%creating%steep%cliff%faces%over%1000%meters%from%sea%level.%%Valley%glaciers%are%still%found%in%large%sections%of%this%province,%primarily%on%Baffin%Bay%in%the%northern%portion%of%the%Shield.%%A%plain,%known%as%the%Coastal%Foreland%can%also%be%found%in%this%province.%%This%section%is%characterized%by%flat%to%hilly%topography%with%an%elevation%over%320%meters.%%%%%%%%%%%%%Slide%8:%The%Kazan%Upland%is%the%province%to%the%west%of%Hudson%Bay%(as%shown%in%the%figure%on%this%slide).%%It%covers%an%area%that%includes%the%northern%portions%of%the%provinces%of%Manitoba%and%Saskatchewan,%as%well%as%the%southern%areas%of%the%Northwest%Territories%and%Nunavut.%%As%with%the%other%provinces,%the%rocks%of%the%Kazan%Upland%are%Precambrian%in%origin%and%consist%of%metamorphic%rocks%(such%as%gneiss%or%quartzite)%or%igneous%rock%(such%as%granite).%Greenstone%(such%as%that%found%near%Flin%Flon%in%northern%Manitoba)%is%a%prominent%rock%feature%found%in%this%area.%%These%rock%structures%tend%to%be%oriented%in%a%northerly%or%northZeasterly%direction,%as%a%result%of%folding%and%faulting%that%occurred%after%formation.%%The%topography%is%again%characterized%by%subdued%relief%with%rolling%hills%that%range%in%altitude%from%220%to%400%meters.%%This%is%due%to%erosion%occurring%over%a%period%of%hundreds%of%millions%of%years.%%The%bedrock%is%covered%with%patches%of%sediment%deposited%by%glacial%deposition%(for%instance%outwash%or%moraine%deposits),%as%well%as%fluvial%or%lacustrine%origin.%Between%the%low%hills%and%ridges,%one%can%find%lakes,%swamps%or%muskegs.%%%Slide%9:%The%largest%province%found%in%the%Canadian%Shield%(in%terms%of%area)%is%known%as%the%James%province.%%As%you%can%see%in%the%figure%on%this%slide,%this%province%extends%from%northern%Manitoba,%through%Ontario%into%Northern%Quebec.%%Like%the%Kazan%Upland%province,%the%James%province%is%composed%primarily%of%igneous%and%metamorphic%rock,%with%alternating%layers%of%gneiss%and%greenstone.%%%%%% Page%|%4%%%Slide%10:%The%final%province%in%the%Canadian%Shield%is%the%Hudson%Bay%Lowlands%(shown%on%the%figure%on%the%slide).%%Unlike%the%previous%provinces%discussed%in%this%module,%this%province%is%considered%lowland%–%an%area%of%land%that%is%low%in%relation%to%the%surrounding%country%and%is%at%a%low%level.%%Only%40%%of%this%province%is%found%on%land,%the%remaining%60%%lies%beneath%Hudson%and%James%bays.%%The%Hudson%Bay%lowlands%are%underlain%by%flatZlying%carbonates%and%sandstones%formed%during%the%Paleozoic%era,%and%in%the%southern%sections%by%clastic%rocks%formed%during%the%Mesozoic%era.%%Another%difference%between%this%province%and%the%others%is%that%the%bedrock%terrain%in%the%Hudson%Bay%Lowland%is%completely%covered%by%a%layer%of%sediments%deposited%by%glacial%and%marine%processes%following%the%last%glacial%period.%%The%inland%portion%of%the%lowlands%coincides%approximately%with%the%highest%level%of%marine%flooding%that%occurred%after%the%disappearance%of%glacial%ice%from%Hudson%Bay%around%7500%years%ago.%%Closer%to%the%coast,%vast%level%plains%of%muskeg%with%thick%peat%accumulations%are%present%due%to%a%thick%marine%layer%of%sediment.%%Uniform,%gentle%offshore%slopes%of%approximately%0.5%meters%per%kilometers%characterize%the%southwestern%coasts.%%Slide%11:%I%would%like%to%shift%our%attention%now%to%some%topographic%features%that%are%found%within%the%Canadian%Shield%region.%%As%mentioned%earlier%in%this%unit,%the%topography%of%the%Canadian%Shield%was%once%very%rugged,%but%over%time%due%to%tectonic%and%more%importantly%weathering%processes,%the%topography%has%become%more%subdued.%%However%some%relief%can%be%found%in%this%vast%region,%for%instance%the%Torngat%and%Laurentian%Mountain%Ranges.%%These%mountain%ranges%are%some%of%the%oldest%in%the%world,%consisting%of%rocks%deposited%over%540%million%years%ago%and%are%part%of%the%Laurentian%Uplands.%The%Torngat%Mountains%are%a%range%found%on%the%Labrador%Peninsula%and%are%part%of%the%Torngat%Mountains%National%Park%(which%will%be%discussed%in%a%later%unit%within%this%module).%%The%highest%point%in%this%range%is%Mount%Caubvick%at%an%elevation%of%over%1,650%meters.%%The%Laurentian%Mountains%are%found%in%southern%Quebec%and%mark%the%boundary%for%the%Laurentian%Upland%province%discussed%in%a%previous%slide%in%this%module.%%The%highest%point%rises%to%an%elevation%of%just%over%1,160%meters%at%Mont%Raoul%Blanchard.%The%Adirondack%Mountains%in%New%York%State%are%an%extension%of%this%mountain%range.%%The%Laurentian%Mountains%were%created%during%the%Grenville%orogeny%or%mountain%building%event%that%occurred%more%than%1%billion%years%ago.%%Both%of%these%mountain%ranges%are%fairly%low%compared%to%the%mountains%of%the%Western%Cordillera%(with%elevations%more%than%2000%meters).%Another%common%topographic%feature%found%in%this%physiographic%region%is%a%monadnock.%%This%is%an%isolated%hill%or%ridge%that%is%composed%of%erosionZresistant%rock.%%A%monadnock%will%typically%be%found%rising%over%a%peneplain.%%%%%% Page%|%5%%%Slide%12:%Due%to%its%long%history%and%formation%billions%of%years%ago,%volcanic%belts%can%be%found%in%the%Canadian%Shield,%even%though%it%is%currently%located%away%from%any%plate%boundaries.%%Originally,%the%Shield%was%an%area%of%very%large%mountains%(probably%in%excess%of%10,000%meters%in%elevation)%with%volcanic%activity.%%%It%is%thought%that%over%150%volcanic%belts%occupy%this%region.%%These%belts%range%in%age%from%600%to%1,200%million%years%old,%and%over%time%have%deformed%due%to%tectonic%processes%and%eroded%due%to%glacial%and%fluvial%processes%to%nearly%flat%plains%found%currently%throughout%the%Canadian%Shield.%%Many%of%the%major%ore%deposits%that%will%be%discussed%in%a%subsequent%unit%are%associated%with%the%volcanic%belts.%One%main%topographic%feature%currently%found%in%the%Canadian%Shield%related%to%these%volcanic%belts%is%the%Blake%River%Megacaldera%Complex.%%This%caldera%complex%is%approximately%2.7%million%years%old%and%is%though%to%consist%of%many%overlapping%calderas%that%range%in%both%size%and%age.%%It%can%be%found%along%the%OntarioZQuebec%border,%covering%an%area%of%over%3000%square%kilometers%(similar%in%scale%to%the%Yellowstone%Caldera%in%Wyoming).%%Research%has%suggested%that%this%location%underwent%three%stages%of%major%volcanic%activity%forming%three%separate%but%nested%calderas:%Misema%caldera%that%was%40%to%80%kilometers%in%diameter%and%formed%approximately%2.7%billion%years%ago;%New%Senator%caldera%that%was%15Z30%kilometers%in%diameter%and%formed%a%few%million%years%later;%and%the%Noranda%Caldera%formed%a%few%million%years%later%than%the%previous%caldera.%%%%Slide%13:%An%additional%striking%topographic%feature%located%in%the%Canadian%Shield%physiographic%region%area%the%Sutton%Ridges.%%These%are%a%striking%feature%because%they%are%ridges%found%in%the%otherwise%largely%flat%Hudson%Bay%Lowlands.%%The%Sutton%Ridges%are%a%series%of%50%kilometers%long,%120%meters%high%ridges%located%south%of%Cape%Henrietta%Maria%in%Ontario%in%the%Hudson%Bay%Lowlands%(Cape%Henrietta%Maria%is%located%at%the%northwestern%tip%of%James%Bay,%where%it%meets%Hudson%Bay).%The%Sutton%Ridges%are%a%series%of%Precambrian%granitic%outcrops%that%curve%in%a%southeasterly%tending%arc%concave%to%the%northeast.%%These%ridges%are%known%as%cuestas,%long,%low%ridges%with%a%gentle%slope%on%one%side%and%a%relatively%steep%face%or%escarpment%on%the%other%side.%%The%northZfacing%slopes%of%the%ridges%dip%2%to%5%degrees%to%the%north,%while%steep%escarpments%prevail%along%the%southern%edge%of%the%ridges.%%%% Page%|%6%%%Slide%14:%The%final%features%I%would%like%to%focus%on%are%the%Archean%terranes.%%Unlike%the%other%features%discussed%in%this%module,%the%Archean%terranes%are%not%a%specific%landform.%%A%terrane%is%defined%as%a%piece%of%crustal%material%that%has%been%broken%off%from%or%formed%onto%one%tectonic%plate%and%accreted%to%the%crust%of%another%plate.%%The%Canadian%Shield%is%a%collage%of%a%number%of%Archean%terranes%that%were%progressively%amalgamated%between%2.45%and%1.24%billion%years%ago.%%The%majority%of%accretion%of%these%terranes%occurred%during%the%TransZHudson%Orogeny%or%major%mountain%building%event%that%occurred%almost%2%billion%years%ago.%%This%accretion%is%the%major%episode%in%geological%history%to%form%the%Canadian%Shield%and%thus%the%Archean%terranes%are%the%building%blocks%for%this%physiographic%region.%%%%Slide%15:%This%concludes%the%unit%on%geology%and%topography%for%the%Canadian%Shield%region.%%You%should%review%the%supplementary%information%that%corresponds%to%this%unit%and%read%the%readings%listed.%%In%the%next%section%we%will%discuss%the%climate%and%glaciers%found%in%this%physiographic%region.%%