CRCT QuestionPrimary seismic waves

a. Are slower than secondaryb. Are the result of shearing

forcesc. Can travel through solids,

liquids and gasesd. Causes Earth’s to roll up and

down*Please have Tier 1 Out

When is tier 2 Earthquakes due?

When is the vocabulary sheet due?

Part 1: Deformation

http://www.youtube.com/watch?v=DppbibMhAXU

Flashcards

Quiz the person sitting next to you,

then switch!!!

Focus vs. Epicenter

Focus is in the point beneath the earth surface where the

rock breaks. Epicenter is above it.

The Epicenter is

the point beneath the earth where

the rock breaks. The

focus is above it.

Organizing! Organize the following phrases into the three major types of stress!

Shearing, Tension, and shearing

Squeezes the rocks of the crust Pushes in opposite direction Pulls the rocks Decreases volume Increases volume Increases density Decreases density Tear and twist

Candy Toss

Question

When plates slide past one another this is what type of boundary?

Answers

Transform

Question

When plates collide this is what type of boundary?

Answers

Convergent

Question

What happens to a rock if it’s undergoing shearing?

Answers

Bends and breaks

Question

What is it called when that Earth BENDS?

Answers

Folding

Question

Squeezing an object describes what kind of stress?

Answers

Compression

Question

Before Lava hits it is called:

Answers

Magma

Question

A volcanic belt that circles the Pacific Ocean is called:

Answers

Ring of Fire

Coffee Talk

All you need to know aboutEarthquakes

Today: seismic waves

II. Seismic Waves-Also known as Earthquake Waves

Seismic Metaphor

Seismic waves ripple like when you throw a stone into a lake or pond

Snap Your Fingers and observe what is happening.

When you snap your fingers, imagine that each finger is a big chunk of rock deep inside the earth's surface. Like your fingers, one rock mass is forced

against another.

Extra: Seismic WavesDeep inside the earth, rocks are constantly

being pressured to move until the strain is so great

the rocks can no longer bear the tension.

Suddenly, there is a movement that releases all the energy--some of which has been building

up for years. This released energy travels

through rocks in the form of vibrations called

seismic waves.

Blue primary waves followed by red secondary waves move outwardin concentric circles from the epicenter of an earthquake off British Columbia and Washington State.

Three Seismic Waves

The energy of all three types of waves is passed from one rock particle to another in the same way one domino hits another and then another in a line of falling dominoes.

These seismic waves cause back-and-forth, side-to-side, and up-and-down motions in the earth. These motions are what people sense during a earthquake.

a. Primary Waves

▪Fastest waves▪P waves▪Moves through solids, liquids, and gases▪Speeds up in denser material▪Push and pull waves

What it Looks like!

Primary waves travel the fastest. P-waves are the first waves to reach the Earth's surface after an earthquake.

b. Secondary Waves

▪S waves▪Slower than P waves▪Travels through solids but not liquids and gases▪Speeds up in denser material▪Movement is side to side

What it Looks Like!

Modeling P and S Waves

I need 10 volunteers! S waves: do "the wave" as they

would in a football stadium, raising their arms and lowering them as the next person raises his or hers.

P Waves: gently grip each other's shoulders and having one pull or push the next person in line.

C. Surface Waves

▪L waves (*think Land)▪Slowest waves▪Originates at the epicenter▪Creates the wave movements on the Earth’s surface▪Causes the most damage

Let’s watch it!

Review #1

Match the following into three separate categories: P, S, L waves

Slowest Fastest Primary Surface Secondary Causes the most damage Travels through solids, liquids, and

gases

Measuring Seismic Waves

III. Seismograph – a. is an instrument that detects

and measures seismic b. Waves *typo in spacing!c. Seismologist – scientists who

study earthquakes, can determine the strength of them

Seismograph

This is an image of a seismograph, an instrument used to record the energy released by an earthquake. When the needle is moved by the motion of the earth, it leaves a wavy line.

When you look at a seismogram, there will be wiggly lines all across it. These are all the seismic waves

that the seismograph has recorded.

Seismogram

The Surface waves are the other, larger waves markedon this seismogram. Surface waves travel slower than

S waves (which are slower than P waves) so they arrive at the seismograph after the S waves.

Surface Waves Arrive Last

Add to Notes

I. Measuring Earthquakes

There are at least 20 different types of measures

3 of them are the Mercalli scale, Richter scale, and the Moment Magnitude scale

Magnitude is a measurement of earthquake strength based on seismic waves and movement along faults

a. The Mercalli Scalerate earthquakes according to their intensity

The intensity of an earthquake is the strength of ground motion in a given place

Is not a precise measurement

But, the 12 steps explain the damage given to people, land surface, and buildings • The Mercalli scale uses Roman

numerals to rank earthquakes by how much damage they cause

B. The Richter Scaleis a rating of the size of seismic waves as measured by a particular type of mechanical seismograph

All over the world, geologists used this for about 50 years

Electric seismographs eventually replaced the mechanical ones used in this scale

Provides accurate measurements for small, nearby earthquakes

Does not work for big, far ones

Locating the Epicenter Since the P waves

travel faster than the S waves, scientists can use the difference in arrival times to see how far away the earthquake occurred.

It does not tell the direction however.

Determining Direction One station can

only learn how far away the quake occurred.

They would draw a circle at that radius.

If three stations combine their data, the quake occurred where the three circles overlap.

How Earthquakes Cause Damage

The severe shaking provided by seismic waves can damage or destroy buildings and bridges, topple utility poles, and damage gas and water mains With their side to side, up and down movement, S waves can damage or destroy buildings, bridges, and fracture gas mains.

Review #2

What is the measurement of an

earthquakes strength?

Tier 2 Options

Option 1: Create a radio announcement for an earthquake warning

Option 2: Letter to the editor

Brainstorm

Help give yourself an outline

Make sure you have incorporated the vocabulary

Tier 2 Earthquakes Rubric

Part 1: Vocabulary (9 points each) Did you accurately communicate the following vocabulary

1. Focus2. Epicenter3. Stress (Tension, shearing, compression)4. Seismic waves (P waves, s waves, surface waves)5. Plate Boundaries6. Faulting7. Folding8. Seismograph9. Richter Scale 10. Plate tectonics

Part 2: Presentation (10 points) Is your project neat, legible, creative, and organized