Earthquakes and Tectonic plates review

Focus

What is the location where the "break" actually happens inside of the earth? Where the earthquake originates.

Seismogram

The record of an earthquake's seismic waves production by a seismograph. (The print out from the machine.)

S Waves

Also called SECONDARY WAVES

tension

stress that pulls rocks apart in opposite directions

Convergent boundary

tectonic plates that collide

faults

The cracks in the Earth's crust along which movements that create earthquakes take place

P Wave

A type of seismic wave that compresses and expands the ground. Move the fastest. Become Surface waves when they reach Earth's surface.

What do scientists use to study the shaking motion of earths crust?

Seismographs

epicenter

The surface location directly overhead of the focus of an earthquake

Which two waves are considered body waves in an earthquake?

P and S waves

Divergent boundary

tectonic plates that divide

Which word best describes the force acting on crustal rocks?

Stress

Seismograph

An instrument that records and measures an earthquake's seismic waves.

Ring of Fire

This feature marks the boundaries of the Pacific plate, where earthquakes and volcanoes are common

Mercalli Scale

Measures the intensity of seismic activity.

Focus

The point inside the Earth where the earthquake begins.

Triangulation

Using three distances waves travel to pinpoint the epicenter of an earthquake.

Transform boundary

tectonic plates that slide past each other

Surface Waves

Seismic waves that are the most destructive

Epicenter

The point on the Earth's surface (continental or oceanic) directly about an earthquakes starting point

Richter scale

A numerical scale used to measure an earthquake's magnitude.

An undersea mountain chain where new ocean floor is produced.

mid-ocean ridge

ocean trench

a long, narrow trench in oceanic crust usually lying above a subduction zone

Theory of Plate Tectonics

scientific theory that explains how volcano formation, earthquakes, mountain formation, and the changing positions of continents is caused by the movements of lithospheric plates

P waves

The fastest wave/arrive first

lithosphere

outermost layer of the Earth containing the crust and uppermost rigid part of the mantle

earthquake

Sudden violent shaking of the earth's ground caused by movement of the crust

Who created the theory of Continental Drift

Alfred Wegner

Earthquake

The shaking and trembling that results from movement of rock beneath Earth's surface.

Circular currents in the mantle caused by heat given off by the core of the Earth.

convection currents

A deep depression on the sea floor caused by the subduction of one plate under another.

trench

Which Is NOT An Evidence Of Continental Drift

Artic fits with antartica

What Occurs At A Convergent boundary

Deep Trenches

seafloor spreading

process that occurs at mid-ocean ridges where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge

Volcano

A vent or fissure in the Earth's surface through which magma and gases are expelled

What Occurs At A Transform Boundary

Earth Quakes

fault

a crack in the Earth's crust along which rocks have shifted

Pangaea

a famous supercontinent that existed about 225 million years ago and has since broken up

Archimedes Principle

Objects displace their weight in fluids

A plate boundary where two plates move away from each other. (Divide)

Divergent Boundary

subduction

process where one tectonic plate moves under another tectonic plate and sinks into the mantle as they converge

The less dense and thicker of the two plate types.

continental crust

D = M / V

Formula for density

The folding of rock upward due to the stress between converging plates

uplift

Mount Everest

tallest mountain in the world

mid-ocean ridge

underwater mountain chain formed as tectonic plates spread apart; wraps around the globe like the seam of a baseball

A break in the Earth's crust where masses of rock slip past each other.

fault

A mid-ocean ridge might be found at this type of plate boundary.

Divergent

supercontinent

a large landmass formed by the convergence of multiple continents

What Boundary Is This

Convergent Boundary

What Occurs At A Divergent Boundary

Mid Ocean Ridges

When two continental plates pull apart a ___ forms.

rift valley

The observation that the continents fit together like puzzle pieces, and may once have been connected, led Alfred Wegener to propose a theory called _

continental drift.

continental drift

idea proposed by Alfred Wegener that the continents move; explained why the same fossils and rock formations were found on now widely-separated continents

subduction zone

a boundary where two plates converge, and because of differences in density, one dives beneath the other

The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.

plate tectonics

Who Created The Theory Sea Floor Spreading

Harry Hess

Density

Amount of mass within a given volume.

What Boundary Is This

Divergent Boundary

plate boundary

The region where two tectonic plates are in contact

The denser and thinner of the two plate types.

oceanic crust

magnetic reversal

a change in Earth's magnetic field such that the positions of magnetic north and magnetic south are interchanged

In which location would you most likely find volcanoes?

along mid-ocean ridges and where a plate is subducted

What Boundary Is This

Transform Boundary

What Is NOT An Evidence Of Sea Floor Spreading

Volcano studies

A major volcanic belt known as ___ circles the Pacific Ocean

the Ring of Fire

Hot spots are _ areas in Earth's mantly.

stationary

A string of islands known as a(n) can form from the collision of two oceanic plates.

island arc

Mountains that are formed by volcanoes along a coastline occur at a(n) plate boundary.

converging

The transfer of heat by movement of currents within a fluid.

convection

Hawaii is forming at a ____.

hot spot

Which layer of the Earth is liquid?

Outer core

Which seismic wave cannot travel through liquid?

S

The inner core is ___.

solid

Before lava reaches the surface, the molten material is called

magma

Volcanoes that form along a mid-ocean ridge occur at a(n) diverging plate boundary.

True