Describe the differences and relation between the lithosphere and asthenosphere.

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Describe the differences Describe the differences and relation between the and relation between the lithosphere and lithosphere and asthenosphere. asthenosphere.

Transcript of Describe the differences and relation between the lithosphere and asthenosphere.

Describe the differences and Describe the differences and relation between the relation between the

lithosphere and lithosphere and asthenosphere.asthenosphere.

Name the three types of Name the three types of plate boundaries and the plate boundaries and the general characteristic of general characteristic of

plate movement along each plate movement along each plate boundary.plate boundary.

What is the magnetic field What is the magnetic field and how is it formed?and how is it formed?

Plate BoundariesPlate Boundaries

ConvergentConvergentDivergentDivergentTransformTransform

Plate TectonicsPlate Tectonics

Explains the configuration of topographic Explains the configuration of topographic features of the Earth- mountains, valleys, features of the Earth- mountains, valleys, volcanoes, islands, oceanic trenches, volcanoes, islands, oceanic trenches, faultsfaults

Tectonic platesTectonic plates Are composed of the Are composed of the lithospherelithosphere Move as a coherent massMove as a coherent mass May contain oceanic crust and May contain oceanic crust and

continental crustcontinental crust

Direction of MovementDirection of Movement

Perpendicular to mid-oceanic ridgesPerpendicular to mid-oceanic ridges

Plate BoundariesPlate Boundaries

ConcentratiConcentration of stored on of stored energy and energy and ultimately ultimately release of release of energyenergy Production Production

of hazardsof hazards

Tectonic Map: locate plate Tectonic Map: locate plate boundaries by symbolboundaries by symbol

Convergent Plate BoundaryConvergent Plate Boundary

Magmatic arcMagmatic arc Oceanic crust subducts under Oceanic crust subducts under

continental crustcontinental crust Melting occurs at about 100 milesMelting occurs at about 100 miles Hot more buoyant material risesHot more buoyant material rises

Volcanic ArcVolcanic Arc

Oceanic and Oceanic and continental crustcontinental crust

Cascade Range; Cascade Range; Andes; AlaskaAndes; Alaska

Characteristics: Characteristics: large volcanoes; large volcanoes; subduction zone, subduction zone, trench, oceanic crust trench, oceanic crust subducts under subducts under continental crustcontinental crust

Convergent Convergent Plate Plate

BoundaryBoundary Map and cross-Map and cross-

section views of section views of the subduction the subduction zonezone

The oceanic Juan The oceanic Juan de Fuca plate de Fuca plate subducts under subducts under the continental the continental North American North American PlatePlate

  

Convergent Plate BoundaryConvergent Plate Boundary

Two oceanic crustsTwo oceanic crusts Oceanic crust subducts under Oceanic crust subducts under

opposing oceanic crustopposing oceanic crust Oldest oceanic crust subductsOldest oceanic crust subducts

Island ArcIsland Arc

Japan, Indonesia, Philippines, Caribbean, Japan, Indonesia, Philippines, Caribbean, Aleutian IslandsAleutian Islands

Convergent Plate BoundaryConvergent Plate Boundary

Earthquakes trace Earthquakes trace the subducting slab the subducting slab to about 500 miles to about 500 miles or 650 kilometersor 650 kilometers

Gold dots represent earthquake hypocenters

Convergent Plate Convergent Plate BoundariesBoundaries

Two continental crustsTwo continental crusts Neither subduct due to buoyancy of crustsNeither subduct due to buoyancy of crusts Mountains formMountains form

IndiaIndia collided collided with Asia with Asia about 40 about 40 million years million years agoago

Mt. Everest, Mt. Everest, 29,000 feet29,000 feet

Divergent Plate BoundaryDivergent Plate Boundary Two plates move apartTwo plates move apart Run through ocean basinsRun through ocean basins

Divergent Plate BoundariesDivergent Plate Boundaries

Mid-oceanic ridges, transform faults and rift valleys, and the formation of the ocean floor are characteristics associated with divergent plate boundaries.

Transform Plate BoundaryTransform Plate Boundary

TransformTransform Plate Boundary Plate Boundary

The tectonic plate The tectonic plate pass by each otherpass by each other

Connect other Connect other plate boundariesplate boundaries

San Andreas FaultSan Andreas Fault

Extension-“Pre-divergent Extension-“Pre-divergent Boundary”Boundary”

Continental crust begins to stretch due to tensional stress.

Basin and RangeBasin and Range Continental crust Continental crust

begins to stretch begins to stretch due to convection due to convection within the within the asthenosphereasthenosphere

A series of A series of mountains and mountains and valleys developvalleys develop

Long Valley Long Valley Caldera is located Caldera is located on the western on the western most portion.most portion.

East Africa Rift ZoneEast Africa Rift Zone An area of An area of

extensionextension Continental Continental

crust is crust is beginning to beginning to pull-apart pull-apart forming a rift forming a rift valleyvalley

HotHot SpotsSpots

Stationary plumes of hot material that Stationary plumes of hot material that initiate at the core/mantle interfaceinitiate at the core/mantle interface

Hawaii: the plume is beneath oceanic crustHawaii: the plume is beneath oceanic crust

Hot SpotsHot Spots

Yellowstone is associated with a hot Yellowstone is associated with a hot spot under continental crustspot under continental crust

Plate TectonicsPlate Tectonics

The The theory theory of plate tectonics is based on of plate tectonics is based on the evaluation of scientific evidence and the evaluation of scientific evidence and observation- observation- The Scientific MethodThe Scientific Method

ContinentalContinental Drift hypothesis Drift hypothesis Seafloor Spreading hypothesisSeafloor Spreading hypothesis

..

Sketch a cross section of a Sketch a cross section of a divergent plate boundary.divergent plate boundary.

Label with the following terms: Label with the following terms: rift valley; rift valley; oceanic ridge; oceanic ridge; oceanic crust; oceanic crust; location of melting and volcanism; location of melting and volcanism; and arrows indicating direction of plate and arrows indicating direction of plate

movement movement

Sketch a cross-section of a Sketch a cross-section of a convergent plate boundary that convergent plate boundary that

contains an oceanic crust.contains an oceanic crust.

Label with the following terms:Label with the following terms: Subduction zoneSubduction zone TrenchTrench Area of meltingArea of melting Area of volcanismArea of volcanism Arrows indicating direction of plate Arrows indicating direction of plate

movementmovement

Name the landform Name the landform associated with oceanic associated with oceanic crust subducting under crust subducting under

continental crust. Oceanic continental crust. Oceanic crust?crust?