Introduction to Tectonic Plates Pictures of

“Tectonic Plates”

Pictures of “Tectonic Plates”

Seismographs Data

▪During the 1950s and 1960s,

scientists set up seismograph

networks to see if enemy nations

were testing atomic bombs.

▪The seismograph also recorded all of

the earthquakes around the planet.

Seismograph Data

▪It turns out that earthquake

epicenters outline the plates.

▪Earthquakes occur

everywhere plates come

into contact with each

other.

Earthquakes around the

worldVolcanoes

▪A vast number of volcanoes

from around the world are

also located where plates

meet.

Tectonic Plates

▪Tectonic plates are able to move because the Earth’s

lithosphere has a higher

strength and lower density than the underlying

asthenosphere.What are “Plates?”

The Earth’s Plates are a lot like the cracked shell of a hard boiled egg.

Earth’s LITHOSPHERE, its solid outer shell, is broken into pieces separated

by jagged cracks.

Tectonic Plates

▪A single plate can be made of all oceanic lithosphere or all continental

lithosphere, but nearly all plates are made of a combination of both.

How Plates Move

Theory of Plate Tectonics:

Pieces of Earth’s Lithosphere are

in slow, constant motion, driven

by convection currents in the

mantle.

This theory explains:

• The Formation,

• The Movement,

• And Subduction of Earth’s Plates

How the Plates Move

▪ The movement of

convection currents in the

mantle is the major force that

causes plate motion.

Plate Movement

▪No plate can budge without affecting the other plates

surrounding it.

▪As the plates move, they collide, pull apart, or grind past each

other.

▪This movement produces changes to Earth’s surface and can include volcanoes, mountain ranges, and

deep-sea trenches.

Energy

▪The movement of the plates also transfers energy from Earth’s interior to the surface.

▪Earthquakes transfer

MECHANICAL energy (energy that moves objects)

▪And volcanoes transfer HEAT energy and MECHANICAL

energy to the surface.

Hot Cocoa Plate Tectonics

Volcanoes

Predict—Observe—

Explain

Earthquakes