Science Unit 3 Earthquake and plate tectonics

What is the Focus

The point where the earthquake originated

What is the epicenter

the point on the surface above the focus

What is released in an earthquake

siesmic waves

What do body waves travel through

the ground

Which wave is the fastest

P waves

What is the movement of P waves

push and pull

which waves are compression waves

p waves

Which is faster P or S waves

P waves

What is the particle movement of S waves

perpindicular (right angles)

What stops S waves

the outer core (liquid)

What happens when P waves go through the core

refracted (change in density)

Where do surface waves travel

along surface

Movement of Surface waves

circular

Slowest and most destructive wave

surface wave

Where do eathquakes occur

along faults

fault

a break where movement has occured

How do we find an earthquake

analyze multiple siesmograms, measuring the difference in P and S wave arrival time, convert the time into a distance using a chart, and locate position

Landslide

Large movement of soil

Tsunami

Eathquake under the water that causes a big wave

Ground liquifacation

saturated soil destabalizes during siesmic shaking

Elastic rebound Hypothesis

Eathquakes occur when forces act on a fault and motion is blocked. As energy builds up energy rock deforms. Edventually the strength of the earthquake is overcome, displacement occurs and elastic energy is released.

5 layers of the earth based on physical characteristics

Lithosphere, asthenosphere, lower mantle, outer core, inner core

3 layers of the earth based on chemical composition

crust, mantle, and core

What is the lithopshere

crust and upper mantle, tectonic plates

What is the special property of the asthenosphere

It is easily deformed, also has convection currents

physical property of the lower mantle

rigid due to pressure

Physical property of outer core

liquid, also creates earths magnetic field

physical property of the inner core

solid due to pressure

Moho Boundry

Boundry between crust and mantle

Matle layer is

largest and rocky

Crust is made up of what

Oceanic and Continental

What is the core made of

iron and nickel

Vibratation of earth caused by rapid release of energy in the lithosphere

eathquake

Can rock bend

yes

aftershock

small eathquake after a big earthquake

What records siesmic waves

siesmograph

What is a record of siesmic waves

siesmogram

Outdated system of measuring eathquakes

Richter scale

Modern system of measuring earthquakes

Moment magnitude

How many station do we need to find an earthquake

3+

How do we know the outer core is liquid

S waves cannot travel through creating the S wave shadow zone

Pangea

name of most recent super continent

3 main evidence of contiental drift

fossils, rock types, and traces of glaciers

what caused criticism for continental drift

Alfred Wagner couldn’t explain why continents drifted

sonar

sound waves to calculate distance from an object

Mid-ocean ridge

What is a long chain of mountains that extends the length of the ocean? It is also one of the longest feature on Earth's surface?

rift valley

central valley of mid ocean ridge

subduction

process of ocean floor sinking beneath a deep ocean trench

As new oceanic crust is created what happens to the old

moves outwards

what is evidence for sea floor spreading

paleomagnetism, earthquake patterns, and age of ocean floor