Plate Tectonics
7th Grade Science
Lesson 1
 Earthquake- vibrations in the earth caused by
sudden release of energy, as a result of the
movement of rocks along a fault
 Seismologist- scientist who studies earthquakes
Lesson 2
 Earthquake Waves
 P-Wave: primary wave, first and compressional
(back and forth)
 S-Wave: secondary, second and moves at right
angles, much rougher
 Surface Waves: Elliptical and back and forth on
surface of earth, most destructive
Lesson 3
 Seismogram- paper that records earthquake
 Seismograph- device that measures an earthquake’s
intensity
 Epicenter – imaginary point on earth that sits on top of
the focus
 Focus – where the earthquake begins inside the earth
Earthquake Diagram
Lesson 4
 Plate Boundary-pieces of broken lithosphere meet, 3 types
Convergent (collide), Divergent (divide) and transform (slide)
 Ring of Fire-encircles the Pacific Ocean, an area of volcanic
and earthquake activity
 Magnitude- measure of total amount of energy released in an
earthquake, each interval 32 times more energy is released
 Intensity- measure of damage done during an earthquake
Lessons 1-4 Challenge
Words
 Liquefaction: strength and stiffness of soil is
reduced by earthquake shaking, occurs in saturated
soils and allows soil particles to move (think of
liquid vs. solid)
 Lithosphere: crust and uppermost mantle, where
earthquakes occur
 Subduction Zone: 2 lithospheric plates come
together
Lesson 5
 Parts of the Earth (inside to outside)-think of our
apple
 Inner Core/like the seeds of an apple
 Outer Core/pocket that holds the seeds
 Mantle/meaty part of the apple-what you eat
 Lithosphere/bite out of the apple-upp.mantle/crust
or a plate
 Crust/skin of the apple
Lesson 6
 Lithosphere: Cool, solid outer shell of earth which is made of
Crust and Upper Mantle and makes up our plates
 Asthenosphere: layer of mantle directly below the lithosphere
and allows the lithosphere to move.
 Mid-Ocean Ridge: A mountainlike landform that develops when
plates separate and new ocean lithosphere forms
 Subduction: The movement of a tectonic plate beneath another
plate Ex. Oceanic lithosphere is more dense and subducts
beneath the Continental lithosphere
 Seafloor Spreading: Mid-Ocean Ridge where magma is is being
pushed out of the crust creating new rock Ex. A Divergent
Boundary like in the Atlantic Ocean between N.America and
Europe/Asia
Lesson 7
 Brittle: describes objects that break easily when force is
applied to them
 Ductile: describes objects that bend, stretch, or flow
when a force is applied to them
 Fault: a fracture in bedrock, along which blocks of rock
on opposite sides of the fracture move Ex. San Andreas
Fault, California
 Plate Tectonics: Theory that lithosphere is broken into
segments/plates that float on the asthenosphere and is
associated with earthquakes, and volcanic activity.