03.05.a1 ocean-ocean convergent boundary one plate moves down = subduction two oceanic plates move...
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03.05.a1
Ocean-Ocean Convergent BoundaryOcean-Ocean Convergent Boundary
One plate moves One plate moves down = down = subductionsubduction
Two oceanic plates Two oceanic plates move toward one move toward one anotheranother
Trench and island arcTrench and island arc
03.05.a1
Sketch ocean-ocean convergence, labeling the Sketch ocean-ocean convergence, labeling the processes in your own wordsprocesses in your own words
Slab releases waterSlab releases water
Eruptions form volcanic Eruptions form volcanic island arcisland arc
Water causes Water causes melting of mantlemelting of mantle
Accretionary Accretionary prismprism
Features and Processes in Ocean-Ocean ConvergenceFeatures and Processes in Ocean-Ocean Convergence
TrenchTrench
03.05.b1
Ocean-Continent Convergent BoundaryOcean-Continent Convergent Boundary
Sketch ocean-continent convergence, labeling the Sketch ocean-continent convergence, labeling the processes in your own wordsprocesses in your own words
Oceanic plate subducted Oceanic plate subducted beneath continentbeneath continent
Oceanic and continental Oceanic and continental plate convergeplate converge
Overlying mantle Overlying mantle meltedmelted
Volcanoes and squeezing Volcanoes and squeezing form mountain beltform mountain belt
TrenchTrench
03.05.c1
Observe the distribution of volcanoes around the Pacific Ring Observe the distribution of volcanoes around the Pacific Ring of Fire of Fire
What doWhat doyou thinkyou thinkcould could explain explain the the overall overall pattern?pattern?
Pacific Ring of FirePacific Ring of Fire
03.05.c2
Subduction beneath Subduction beneath oceanic plates = island oceanic plates = island arcs (e.g., Japan)arcs (e.g., Japan)
Oceanic plates subducted Oceanic plates subducted on both sideson both sides
Subduction beneath continental Subduction beneath continental plates = mountain belts with plates = mountain belts with volcanoes (e.g., Andes)volcanoes (e.g., Andes)
Explain the Pacific Ring of Fire, including why Explain the Pacific Ring of Fire, including why the west and east sides are differentthe west and east sides are different
Spreading in East Spreading in East Pacific RisePacific Rise
03.05.d
Continent-Continent Continent-Continent ConvergenceConvergence
Subduction Subduction brings continents brings continents closercloser
Subduction Subduction of oceanic of oceanic part of platepart of plate
Continents Continents collidecollide
Two continents collideTwo continents collide
03.05.d3
Sketch a continental collision, labeling the Sketch a continental collision, labeling the processes in your own wordsprocesses in your own words
Pieces sliced offPieces sliced off
Continental collision = wide zone of deformationContinental collision = wide zone of deformation
Continental plate Continental plate buoyant, so buoyant, so subduction endssubduction ends
Few volcanoesFew volcanoes
Thick crust = high elevationThick crust = high elevation
03.06.a1
Transform BoundaryTransform Boundary
Observe how these two “plates” are moving Observe how these two “plates” are moving past each otherpast each other
Transforms Transforms link other link other types of plate types of plate boundariesboundaries
Plates move Plates move horizontally horizontally
past one past one another on another on
transform transform boundariesboundaries
Transforms link Transforms link spreading segments spreading segments in mid-ocean ridgesin mid-ocean ridges
03.06.a2
Observe the pattern of the Mid-Atlantic RidgeObserve the pattern of the Mid-Atlantic Ridge
Transforms link Transforms link spreading spreading segmentssegments
Spreading Spreading segmentssegments
Sketch a transform boundary, labeling the Sketch a transform boundary, labeling the processes in your own wordsprocesses in your own words
03.06.b1
Observe plate boundaries near the west coast of Observe plate boundaries near the west coast of North America (green lines are transform boundaries)North America (green lines are transform boundaries)
03.07.a1
What Moves the Plates?What Moves the Plates?
Ridge pushRidge push
Slab pullSlab pull Other forces, such as Other forces, such as convection in mantleconvection in mantle
03.07.b1
Rates of Relative Plate MovementRates of Relative Plate Movement
Which plate boundaries have the fastest rates?Which plate boundaries have the fastest rates?
Some move faster than othersSome move faster than othersPlates move cm/yearPlates move cm/year
03.07.d1
Geometry of Plate BoundariesGeometry of Plate Boundaries
Observe how the motion of these two plates varies as the Observe how the motion of these two plates varies as the boundary changes orientationboundary changes orientation
Transform Transform boundaries link boundaries link other types of plate other types of plate boundaries, like two boundaries, like two spreading centers spreading centers or a spreading or a spreading center with a center with a subduction zonesubduction zone
As boundary changes As boundary changes orientation, plates orientation, plates move horizontally past move horizontally past one anotherone another
Spreading along Spreading along this orientation this orientation
03.07.d1
Geometry of Plate Boundaries IIGeometry of Plate Boundaries II
Observe how the motion between the North American and Observe how the motion between the North American and Pacific plates varies as the boundary changes orientationPacific plates varies as the boundary changes orientation
Transform boundary here Transform boundary here (Queen Charlotte fault), with (Queen Charlotte fault), with plates moving horizontally plates moving horizontally past one anotherpast one another
As boundary bends, As boundary bends, becomes convergent becomes convergent (Pacific plate subducted (Pacific plate subducted beneath NA)beneath NA)
03.08.a1
Sediment thickens away Sediment thickens away from ridge (had more from ridge (had more time to accumulate)time to accumulate)
Volcanic rocks in Volcanic rocks in crust youngest near crust youngest near ridge (just formed)ridge (just formed)
Test of Plate Tectonics Is Age of Seafloor Test of Plate Tectonics Is Age of Seafloor and Thickness of Sedimentand Thickness of Sediment
Drill Drill corescores
SedimentSediment
Volcanic rocksVolcanic rocks
Formation of Linear Island Formation of Linear Island and Seamount Chainsand Seamount Chains
Plate moves over a hot spotPlate moves over a hot spot
Lines of islands and Lines of islands and seamounts (e.g., Hawaii)seamounts (e.g., Hawaii)
Volcano Volcano forms over forms over a hot spota hot spot
Volcanoes become inactive as Volcanoes become inactive as area moves away from hot spotarea moves away from hot spot
Plate subsides Plate subsides as cools, so as cools, so islands become islands become seamountsseamounts
03.08.c
03.09.a1
Why is South America LopsidedWhy is South America LopsidedObserve the Observe the features features around South around South AmericaAmerica
Envision a Envision a cross section cross section from west of from west of
South South America America
to the Mid-to the Mid-Atlantic Atlantic
RidgeRidge
03.09.b1
Compare this cross section with the Compare this cross section with the one you envisionedone you envisioned
Eastern edge of Eastern edge of continent not a continent not a plate boundary plate boundary (passive margin)(passive margin)
Spreading along Spreading along mid-ocean ridgemid-ocean ridge
Subduction beneath Subduction beneath western edgewestern edge
Andes (mountains and Andes (mountains and volcanoes) over subduction volcanoes) over subduction zone, with trench offshorezone, with trench offshore
03.09.c
Evolution of Evolution of South AmericaSouth America
Observe the Observe the evolution of evolution of South America, South America, beginning with beginning with continental rifting continental rifting away from South away from South AmericaAmerica
Middle Middle MesozoicMesozoic(140 m.y ago)(140 m.y ago)
Late Late MesozoicMesozoic(100 m.y ago)(100 m.y ago)
PresentPresent
03.10.a1
Investigation: Where is the Safest Place to LiveInvestigation: Where is the Safest Place to Live
Identify possible plate boundaries in this area and indicate Identify possible plate boundaries in this area and indicate whether the boundary is divergent, convergent, or transformwhether the boundary is divergent, convergent, or transform
Continent Continent AA
Continent Continent BB
Identify where you would get earthquakes and volcanoes, Identify where you would get earthquakes and volcanoes, and then determine where it is safest to liveand then determine where it is safest to live
03.10.a
Sketch the geometry of the plates in the subsurface, using Sketch the geometry of the plates in the subsurface, using figures in the textbook as a guide to the geometries of the figures in the textbook as a guide to the geometries of the plates and thickness of the lithosphere, oceanic crust, and plates and thickness of the lithosphere, oceanic crust, and continental crustcontinental crust