Download Landforms depend on types of crust that meet

Plate Tectonics
8-3.6 Explain how the theory
of plate tectonics accounts for
the motion of the lithospheric
plates, the geologic activities
at the plate boundaries, & the
changes in the landform areas
over geologic time.
Continental Drift EQ 8-3.6 :
Justify the hypothesis of
continental drift based on
Earth’s evidences.
Continental Drift
• What is continental• The hypothesis that continents
drift?
have slowly moved to their current
locations. Plates were once one
large landmass called Pangaea.
• large sections of Earth’s crust
• What are
lithospheric plates?
•
Very
slowly-about
1-10
cm
per
• How fast do plates
year
move?
(see G.O.) Evidences
• What are
• 1. fossil evidence: same
evidences of
fossil found on multiple
continental drift? continents
• 2. climate clues: tropical
plants were found in cold
Antarctica & glacial deposits
found in Africa
• 3. rock clues: similar rock
structures found on different
continents
• 4. Pangaea: continents fit
together like puzzle pieces
Plate Tectonics EQ 8-3.6 :
How does the theory of
plate tectonics account for
the changes in the
landform regions over
time?
Plate Tectonics
• What is the theory of • An explanation of how many of
Earth’s features form
plate tectonics?
• What are convection • The heating, rising, cooling &
sinking of magma within the
currents?
asthenosphere, caused by
uneven heating
• They make the lithospheric
• How do “ccs” play a
plates move, changing the
role in plate tectonics?
sizes, shapes & positions of
Earth’s continents and oceans
Plate Boundary EQ 8-3.6:
• Explain how the Earth’s lithospheric plates
move at the three types of plate
boundaries, and discuss how this
movement creates different types of
landforms or events at each.
Convergent Boundary
• Two plates colliding • Landforms depend on types
of crust that meet
• Mountain ranges:
• 2 continental plates
converge; both plates buckle
& push up
• more dense oceanic plate
• Subduction zones:
slides under less dense
continental plate (or another
oceanic plate) & some crust
is destroyed (melted)
Divergent Boundary
• Two plates moving • Most located along midapart
ocean ridges
• Sea floor spreading • occurs at these ridges when
new floor (crust) forms
because magma rises up &
spreads apart on both sides
of the ridge (right & left)
pushing away old material
(crust or rock) & hardening
to become new crust
Transform Boundary
• two plates sliding • earthquakes
past each other
frequently occur
Plate Boundary Drawings
• Landforms depend on types of crust that
meet
• Crust is destroyed (melted)
• occurs at these ridges when new floor (crust)
forms because magma rises up & spreads
apart on both sides of the ridge (right & left)
pushing away old material (crust or rock) &
hardening to become new crust