VOLCANO MODULE

PLATES TECTONICS - STUDY GUIDE QUESTIONS & PLATES QUIZ

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PLATE TECTONICS - VIDEO


Write the 10 questions & answers on notebook paper.

• Use notes as needed
• Ask for handout to help with questions
• Title page:  PLATE TECTONICS
• Watch the video & do the INTERACTIVE before answering questions
• PLATE TECTONICS- video #3
• PLATES INTERACTIVE - interactive #4 (click on heavy black line)
• DUE:  Friday, 5/13

1. Do plates move horizontally, vertically, or both?


2. What do plates float on?


3. What type of rock are oceanic plates made of?


4. What type of rock are continental plates made of?


5. What is the name of the are where the crust goes back down into the Earth?


6. What is the process of new crust formation called?


7. When two continental plates collide, what types of mountains are formed?


8. What is the name of the supercontinent that existed about 200 million through 100 million years ago?

9. Who first stated the theory of continental drift?


10. Name a fossil that was found on different continents and was used to support the theory of continental drift.


To complete the quiz - circle the correct answer.  (get hand out)
TITLE:       PLATES QUIZ #1
DUE:  Friday, 5/13

LIQUEFACTION FROM AN EARTHQUAKE

LIQUEFACTION

Liquefaction is the process of loose soil acting like a liquid during an earthquake.

Most of the time, buildings and homes are built upon solid bedrock.  However, building also happens on what seems like solid ground.  But underneath a solid layer of compact sediment, there is lurking a loose layer of sandy soil or soil that has been saturated with water.  During the shaking of a powerful earthquake, this loose soil will act like quicksand.  When liquefaction occurs, the homes and buildings atop this soil can sink or fall over when their foundations loosen or break apart.  The surface of the ground will become very uneven and unstable.  Crevices and gaps open up.  Roads and sidewalks break into pieces and become hazardous.

These are not the only effects of liquefaction.  Loose, sandy soil, or the water saturated soil underneath the compact layer of sediment can make its way up to the surface.  The columns of rising sandy soil are called sand dikes.  When the sand emerges on the surface it is called a sand boil.  The results of this liquefaction phenomenon are often seen after high magnitude earthquakes.  Street pavement will break apart, and sand boils can be seen on roadways and other areas.  Sewer channels underneath streets can rise up during liquefaction.  As a result, the manhole cover you see everyday on your way to school could be several inches to a couple of feet higher than the surface of the road.  This is a common side effect of liquefaction.  Other underground structures can break also; important things like gas and water lines.

Video #1



SOIL LIQUEFACTION EFFECTS

Click on the INTERACTIVE MAP to view current earthquakes & volcanoes

WHAT IS A SEISMOGRAPH?

WHAT IS A SEISMOGRAPH?
Video #1

SEISMOGRAPH

Click on the link:
EARTHQUAKE SCIENTIST

EARTHQUAKES

Earthquakes are the breaking and cracking of the rocks inside the continental plates. The breaks happen after stress has built up in the surrounding area. There are usually very few or no quakes when the plates move slowly. When there is a fast movement of the plate, there is a snap (like breaking a cracker).     

 BASIC EARTHQUAKE FACTS #1    (study jams)
Earthquakes occur when vast plates, or rocks, within the Earth suddenly break or shift under stress, sending shock waves rippling.·                    

Sudden movement along the fault causes the ground to shake.·                    

 Most earthquakes occur along fractures in the Earth's crust called faults. ·                      

Intraplate quakes occur far from plate edges and happen when stress builds up and the Earth's crust is stretched or squeezed together until it rips.·                    

 There are several different types of faults. Each can be a few inches or many hundreds of miles long. They can be horizontal, vertical, or at an angle.                      

Earthquake waves are measured on sensitive instruments called seismographs.·                      
The Richter scale assigns quakes a number based on the power of its seismic waves.·                     

 Thousands of quakes occur every day around the globe, most of them too weak to be felt.·                      

Every year about 10,000 people, on average, die as a result of earthquakes. 

Where Do Earthquakes Happen?

Earthquakes occur all the time all over the world, both along plate edges and along faults.

Most earthquakes happen within the ‘Ring of Fire’ around the Pacific Ocean. Alaska experiences a 7.0 earthquake at least once a year. California gets about 10,000 quakes a year, but most are unnoticed except by the seismograph machines.

It is thought that there are as many as 500,000 earthquakes every year, although only 100,000 can be felt at all and only about 100 of those actually cause any damage.

All around the world people are using their better understanding of earthquakes to design safer buildings and transport systems so, although we can’t do anything to stop the Earth shaking, we can minimize the damage caused.

Along Plate Edges

Most earthquakes occur along the edge of the oceanic and continental plates. The earth's crust (the outer layer of the planet) is made up of several pieces, called plates. The plates under the oceans are called oceanic plates and the rest are continental plates. The plates are moved around by the motion of a deeper part of the earth (the mantle) that lies underneath the crust. These plates are always bumping into each other, pulling away from each other, or past each other. The plates usually move at about the same speed that your fingernails grow. Earthquakes usually occur where two plates are running into each other or sliding past each other.

Earthquakes can also occur far from the edges of plates, along faults. Faults are cracks in the earth where sections of a plate (or two plates) are moving in different directions. Faults are caused by all that bumping and sliding the plates do. They are more common near the edges of the plates.

Why Do Earthquakes Happen?

Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly; the rocks catch on each other. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs. During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they get stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus (on top of the ground) is called the epicenter of the earthquake.

Earthquake-like seismic waves can also be caused by explosions underground. These explosions may be set off to break rock while making tunnels for roads, railroads, subways, or mines. These explosions, however, don't cause very strong seismic waves. You may not even feel them. Sometimes seismic waves occur when the roof or walls of a mine collapse. These can sometimes be felt by people near the mine. The largest underground explosions, from tests of nuclear warheads (bombs), can create seismic waves very much like large earthquakes. This fact has been exploited as a means to enforce the global nuclear test ban, because no nuclear warhead can be detonated on earth without producing such seismic waves.

More than buildings collapse when an earthquake hits. The land itself is totally changed. You can see scars across the landscape. Those scars appear when one block of land has moved compared to another. Roads often change their placement. They either become uneven or just crack. Streams can also change course. Sometimes rocks can fall and block the stream. Other times, the land is even lowered in certain areas. When it's lower, it's easier for the water to flow in the new direction.

Changes also happen on larger scales. Fault valleys and troughs can be created. These areas have large amounts of fracturing (the fracture zone is large). After the land has opened up, weather begins to act on the area and erosion follows. Slowly, new valleys are created.
 

Waves Across The Land
You might think, "If it only happens in one place, why can you feel them hundreds of miles away?" The crack happens where the quake starts. Ripples then move out in waves across the plate. Those waves are called seismic waves. Those waves shake everyone up within a specific area. 

When scientists analyze an earthquake they look at several parts. They find out where the focus is. The focus is the exact point where the earthquake started. It is usually many miles/kilometers below the surface of the Earth. Scientists also look to see where the epicenter was. The epicenter is the point on the surface directly above the focus. When you think about the epicenter, try to remember there is actually a crack in the crust many kilometers below. 

Elastic Rebound Theory

Here we have a landscape with a road, a fence, and a line of trees crossing a fault. As the crust moves, the rocks adjacent to the fault are deformed out of shape (in reality the deformation is spread across many kilometers - if it were this obvious, earthquake prediction would be easy). Eventually the rocks are so stretched out of shape that they cannot bear the stress any longer. The fault slips, and the stage is set for the next cycle of strain buildup and release.

Epicenter and Focus

TYPE OF EARTHQUAKE WAVES

Primary Waves (P Waves)

•A type of seismic wave that compresses and expands the ground

•The first wave to arrive at an earthquake

Secondary Waves (S Waves)

Surface Waves

Several types, travel along the earth's surface or on layer boundaries in the earth. The slowest waves but the ones that do the damage in large earthquakes.

•A type of seismic wave that moves the ground up and down or side to side

How do scientists calculate how far a location is from the epicenter of an earthquake? 

Scientists calculate the difference between arrival times of the P waves and S waves

•The further away an earthquake is, the greater the time between the arrival of the P waves and the S waves

How are Earthquakes Measured? 

Richter Scale

MODIFIED MERCALLI SCALE INTERACTIVE #1 - click on the graphic

 

EARTHQUAKE WAVES

Identify the P & S waves, Focus

Seismic Waves in the Earth

Built For Quakes
After an earthquake, you can turn on the television and see all sorts of footage showing buildings that didn't quite survive. Buildings are built for up and down forces. If you jump on your floor a bunch of times your house will stay up. Earthquakes have forces that move side to side. Houses aren't built for that direction of energy. When the Earth moves side to side, the house can't wobble and it snaps. The walls collapse and roof falls in. Really tall skyscrapers are well designed for earthquakes. They are built to withstand strong winds. When strong winds happen, they can move side to side and sway if needed. 

EARTHQUAKE - INTERACTIVE #2

• complete the module to learn more about Earthquakes
• complete the Introduction & Simulation

SAVAGE EARTH Animated Graphics:  click on highlighted words & draw in your notes. Normal Fault Blind Thrust Fault Strike-Slip-Fault Dip-Slip Fault Mid-Ocean Ridge Subduction  Primary Wave Secondary Wave Surface Wave Tsunami Spread

WORDS TO KNOW:

focus

epicenter

amplification

divergent boundary

elastic rebound

foreshocks

liquefaction

normal fault

strike-slip fault
thrust fault

fault
focus
landslide
mantle
P  wave
ocean spreading ridge
Richter scale
ring of fire 
S  wave
seismic wave
strike slip
subduction
transform fault

Use the Earthquake glossary for terms & definitions

• some of terms may be explained in the notes, check the words in glossary

earthquake vocabulary glossary

PLATE TECTONICS

PLATE TECTONICS IN ACTION

The basic idea behind plate tectonics is that there are eight major plates on the surface of the Earth. There are also bunches of minor plates. The plates are like the skin of the planet. They constantly move around the planet. 

• When we say constantly moving, we're talking centimeters each year. You couldn't sit down and watch it happen. Or can you? You could watch it happen if you watched an earthquake. 

As new crust is created in a particular location on Earth, it forms what resembles giant plates. One side of the plate is where new crust is being created, while the other side is where older crust is being destroyed. 

PLATE TECTONICS - Interactive #1

Using modern equipment, scientists known as oceanographers have been able to measure and map out the ocean floor. What these scientists have discovered has helped explain how it is that continents are able to move around on the Earth’s crust.

Located deep beneath the waves on the ocean floor almost exactly halfway between the continents are raised areas known as ridges. These ridges are similar to under-water mountain ranges. At other locations we find extremely deep trenches, some reaching many thousands of feet in depth.

Many scientists believe that the ridges represent areas where new crust is being formed as hot magma escapes from the Earth’s core and spreads outward. As the seafloor spreads outward away from the area where magma is being released, the continents are carried across the sea, riding on top of the sima crust. 

As new crust is created, older crust submerges back into the mantle, being melted once again. It is believed that the deep ocean trenches are locations where crust is being lowered back into the Earth’s core.

The amount of time that it takes for crust to be created and later destroyed is approximately 100 million years. Thus, most crust has a lifetime of around 100 million years.

Because continents do not fall back into the Earth’s mantle, they survive much longer. Many parts of the continents we see today are almost as old as the Earth itself.

Geologists refer to this process as plate tectonics. As we study plate tectonics, a picture emerges of very old continents riding on top of much younger and ever moving plates. These plates move extremely slowly, at a rate of only about 10 cm per year.

PLATE TECTONICS

Type of Crust	Average Thickness	Average Age	Major Component
Continental Crust	20-80 kilometers	3 billion years	Granite
Oceanic Crust	10 kilometers	Generally 70 to 100 million years old	Basalt

The theory of plate tectonics (meaning "plate structure") was developed in the 1960's. This theory explains the movement of the Earth's plates (which has since been documented scientifically) and also explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and many other geologic phenomenon.

The plates are moving at a speed that has been estimated at 1 to 10 cm per year. Most of the Earth's seismic activity (volcanoes and earthquakes) occurs at the plate boundaries as they interact.

UPPER MANTLE
  - Lithosphere (Sial and Sima)
  - Asthenosphere (Molten Rock River)
  - Mesosphere
LOWER MANTLE
OUTER CORE (Liquid Iron and Nickel)
INNER CORE (Solid Iron Compounds)


The top layer of the Earth's surface is called the crust (it lies on top of the plates). Oceanic crust (the thin crust under the oceans) is thinner and denser than continental crust. 
Crust is constantly being created and destroyed; oceanic crust is more active than continental crust.

The CRUST

The Earth's Crust is like the skin of an apple. 

• It is very thin in comparison to the other three layers. The crust is only about 3-5 miles (8 kilometers) thick under the oceans(oceanic crust) and about 25 miles (32 kilometers) thick under the continents (continental crust). 
• The crust of the Earth is broken into many pieces called plates. The plates "float" on the soft, plastic mantle which is located below the crust. 
• These plates usually move along smoothly but sometimes they stick and build up pressure. The pressure builds and the rock bends until it snaps. When this occurs an Earthquake is the result!

Notice how thin the crust of the Earth is in comparison to the other layers. The seven continents and ocean plates basically float across the mantle which is composed of much hotter and denser material.

Under the crust is the rocky mantle, which is composed of silicon, oxygen, magnesium, iron, aluminum, and calcium. 

Think of the molten rock in the
• The upper mantle is rigid and is part of the lithosphere - These plates make up the top layer of the Earth 
• Directly under that layer is the asthenosphere.(together with the crust). The lower mantle flows slowly, at a rate of a few centimeters per year. The asthenosphere is a part of the upper mantle that exhibits plastic properties. It is located below the lithosphere (the crust and upper mantle), between about 100 and 250 kilometers deep. 
• It's a flowing area of molten rock. There is constant heat and radiation given off from the center of the Earth. That energy is what constantly heats the rocks and melts them. The tectonic plates are floating on top of the molten rock and moving around the planet. Think of it as ice floating at the top of your soda. When the continents and plates move it's called continental drift. 
• asthenosphere, not as rock, but as a liquid. It has currents and it flows just like any other liquid. When the floating plates spread apart, it's called a spreading center. 
• When they are moving together, it's called a subduction zone. 
• When they are forced together, it is called a zone of convergence. One of the plates usually moves under the other in a zone of convergence. As the plate moves down into the asthenosphere it begins to melt. The place where they meet has a crack or a trench. Some of the deepest parts of the oceans are these trenches. .

TYPES OF PLATE MOVEMENT: 

Divergence, Convergence, and Lateral Slipping

At the boundaries of the plates, various deformations occur as the plates interact; they separate from one another (seafloor spreading), collide (forming mountain ranges), slip past one another (subduction zones, in which plates undergo destruction and remelting), and slip laterally.

Divergent Plate Movement: Seafloor Spreading Seafloor spreading is the movement of two oceanic plates away from each other (at a divergent plate boundary), which results in the formation of new oceanic crust (from magma that comes from within the Earth's mantle) along a a mid-ocean ridge. Where the oceanic plates are moving away from each other is called a zone of divergence. Ocean floor spreading was first suggested by Harry Hess and Robert Dietz in the 1960's.

Convergent Plate Movement:When two plates collide (at a convergent plate boundary), some crust is destroyed in the impact and the plates become smaller. The results differ, depending upon what types of plates are involved.     Oceanic Plate and Continental Plate - When a thin, dense oceanic plate collides with a relatively light, thick continental plate, the oceanic plate is forced under the continental plate; this phenomenon is called subduction. Two Oceanic Plates - When two oceanic plates collide, one may be pushed under the other and magma from the mantle rises, forming volcanoes in the vicinity.       Two Continental Plates - When two continental plates collide, mountain ranges are created as the colliding crust is compressed and pushed upwards.

Lateral Slipping Plate Movement:When two plates move sideways against each other (at a transform plate boundary), there is a tremendous amount of friction which makes the movement jerky. The plates slip, then stick as the friction and pressure build up to incredible levels. When the pressure is released suddenly, and the plates suddenly jerk apart, this is an earthquake.

*******************************.

PLATE TECTONICS - LAUNCH INTERACTIVE #2

• complete the module 
• click on the following topics in the box on the left side of the module "DEEPER DISCOVERY",
• PLATE TECTONICS > INTERACTIVE
• BREAK UP OF PANGAEA
• PLATE BOUNDARIES
• PLATE MOVEMENTS
• PLATE TECTONICS QUIZ #2 - add score to study guide notebook paper page.

Scientific Evidence

How do we back up these ideas? Scientists have traveled all over the Earth and found evidence that supports the ideas of plate tectonics. First, they looked at the continents. Ever notice how Africa and South America look like they could fit together? Scientists did. They cut up a map, moved the continents close together, and came up with a huge landmass called Pangaea (one super-continent). 

Scientists also looked at the fossils (long-dead animal bones and plants) on the different continents. They found that fossils on Australia were similar to the ones in Southern Asia. They think the same plants once lived on the continents, but when they split apart, new plants developed. When they were digging, they also looked at the types of rocks. The West Coast of Africa has very similar rock formations to those on the East Coast of South America. They are too similar to be a coincidence. 

PLATE & EARTHQUAKE INTERACTIVE #3 

WORDS TO KNOW:

• oceanographers
• ridges
• lithosphere
• asthenosphere
• continental crust
• oceanic crust
• transform plate boundary
• plate tectonic
• seafloor spreading
• lateral slipping plate
• convergent plate
• subduction zones
• zone of divergence
• lateral slipping plate movement
• crust

PANGAEA

BREAK-UP OF PANGEA #1

Pangaea – Whole Land

Looking at a globe reveals coincidences that are difficult to ignore. The Eastern coast of South America seams to fit perfectly, almost like a puzzle, into the Western coast of Africa. At the same time, North America can be rotated slightly, and made to fit comfortably next to Europe, and Asia.

These clues have lead geologists and other scientists to examine the relationships of other clues. Ancient fossil records show that the same plants and animals lived along the Eastern coast of South America, as did along the Western coast of Africa, as did other plants and animals along the coasts of North America and Europe. 

With this over whelming evidence, it became clear that at some point many millions of years ago, these continents must have in fact been connected. 

Scientists now believe that about 250 million years ago, a supercontinent known as Pangaea existed. This supercontinent was made up of all the continents on Earth. Over time, these continents have broken apart, and slowly drifted away from one another. This drift continues today, so that the form the Earth takes today is not by any means the final shape of our Earth.


Complete the Module - PLATE TECTONICS #2


QUESTIONS -  

• write question & answer neatly on notebook paper - PANGEA QUESTIONS

1. What is Pangaea?
2. What caused Pangaea to break up?

WORDS TO KNOW:

• pangaea
• geologist

WIND - SCAVENGER HUNT

WIND SCAVENGER HUNT

• Use the websites to answer the following questions.
• DUE:  Thursday, April 24

WIND MOVEMENT  http://www.kidsgeo.com/geography-for-kids/0087-wind-movement.php

·        3 important factors affect the direction that wind blows? THE CORIOLIS EFFECT http://www.kidsgeo.com/geography-for-kids/0089-coriolis-effect.php ·        What is the coriolis effect? WIND FRICTION http://www.kidsgeo.com/geography-for-kids/0090-wind-friction-effect.php ·        What things interfere with wind, changing its direction & speed – give examples ·        Whre is the effect of friction important? WIND SPEED http://www.kidsgeo.com/geography-for-kids/0091-wind-speedt.php ·        Wind speed is primarily affected by? Explain TRADE WINDS  http://www.kidsgeo.com/geography-for-kids/0094-trade-winds.php ·        Which direction do winds in Northern Hemisphere move? ·        Which direction do winds in Southern Hemisphere move? ·        What are easterlies winds? WESTERLIES http://www.kidsgeo.com/geography-for-kids/0095-westerlies.php ·        What are westerlies wind? ·        What is the jet stream? POLAR EASTERLIES  http://education.nationalgeographic.com/education/encyclopedia/wind/?ar_a=1 ·        What are polar easterlies? SEA & LAND BREEZES  http://www.kidsgeo.com/geography-for-kids/0098-sea-land-breezes.php ·        How do sea & land breezes work?  Do day & nite differ? (DRAW) MOUNTAIN & VALLEY BREEZES  http://www.kidsgeo.com/geography-for-kids/0099-mountain-valley-breezes.php What are mountain & valley breezes?   Do day & nite differ?   (DRAW) WIND – HISTORY   http://kids.mtpe.hq.nasa.gov/archive/nino/global.html Answer the following questions: ·        What winds would Columbus have used to travel from Spain to the Caribbean? ·        Which winds would he have needed to return to Europe? ·        Would winds have favored European explorers seeking to travel east around the tip of Africa? ·        Wind is caused by? ·        What scale describes & classifies the different wind speeds is the? ·        Wind direction is measured by a? ·        Wind speed is measured with a ? ·        What are the narrow bands of strong winds called which move around the world between about six and twelve miles high? ·        High & low pressure try to reach? ANSWER QUIZ QUESTIONS  http://goo.gl/0O90Fq DRAW & LABEL – Windward & Leeward winds