tectonic plates week 2

I have also provided the teachers with some USEFUL and FUN activities that the children can do in relation to tectonic plates.

Activity 1. Snack Tectonics

Title: Snack Tectonics
Summary: Students create a tasty model that illustrates plate tectonic motions.
year level: 5-8
Time: 15 minutes prep time and 20-30 minutes class time
Student Learning Outcomes:
•Students learn how Earth’s tectonic plates (lithosphere) ride atop the slow flowing asthenosphere layer.
•Students understand how plates interact at their boundaries.
Lesson format: Hands-on activity
National Standards Addressed:
• 5-8: Content Standard A: Science as Inquiry
• 5-8: Content Standard D: Structure of the Earth System


MATERIALS:
For each student:
•One large cracker broken in half (i.e., two square crackers)
•Two 3-inch squares (approx.) of fruit roll up
•Cup of water
•Frosting
•Sheet of wax paper
•Plastic knife or spoon
•Directions overheads ( provided below)

DIRECTIONS:

1. Make the model
a.Give each student about a square foot= 929cm of wax paper and a large dollop of frosting. Instruct students to spread frosting into a layer about half a cm thick.
b.Tell students that the frosting in this model represents the asthenosphere, the viscous layer on which Earth’s plates ride. The plates in this model are represented by fruit roll up (oceanic crust which is thin and dense) and the crackers (continental crust which is thick but less dense).
2. Divergent plate boundary
a.Instruct students to place the two squares of fruit roll up (oceanic plates) onto the frosting right next to each other.
b.Press down slowly on the fruit roll ups (because they are dense and will sink a bit into the asthenosphere) as you slowly push them apart about half a cm.
c.Notice how the frosting is exposed and pushed up where the plates are separated? This is analogous to how magma comes to the surface where real plates are moving apart at divergent plate boundaries. Most divergent plates boundaries are located within oceanic crust. When plates begin to pull apart at continents, rift valleys are made, like the great rift valley in Africa, which can become the bottom of the sea floor if the plates continue to pull apart.
3. Continental-oceanic collision
a.Instruct students to remove one of the fruit roll ups from the frosting. (They can eat it if they wish!)
b.Tell students to place one of the cracker halves lightly onto the frosting asthenosphere next to the remaining fruit roll up piece. The cracker represents continental crust, which is thicker and less dense than oceanic crust (fruit roll up). It floats high on the asthenosphere so don't push it down.
c.Gently push the continent (cracker) towards the ocean plate (fruit roll up) until the two overlap and the cracker is on top. The oceanic plate is subducted below the continental one.
4. Continent-continent collision
a.Tell students that they will next model what happens when two continents collide. Have them remove both the cracker and fruit roll up from the frosting asthenosphere. (Students can eat or discard the fruit roll up.)
b.Place one edge of both crackers into the glass of water for just a few seconds.
c.Place the crackers onto the frosting with wet edges next to each other.
d.Slowly push the crackers towards each other.
e.Notice how the wet edges crumple? This is how mountains are made at convergent plate boundaries! When continents move towards each other there is nowhere for the rock to go but up!
5. Transform plate boundaries
a.Pick the two crackers up off the frosting and turn them around so that two dry edges are next to each other.
b.Push one cracker past the other to simulate a transform plate boundary like the San Andreas fault!
6. Final step: eat all remaining model materials (except, of course, wax paper and plastic utensils!)

ASSESSMENT:
Have students draw what each situation looks like in cross section (by looking at the edge of their model)

BACKGROUND INFORMATION:
The main force that shapes our planet’s surface over long amounts of time is the movement of Earth's outer layer by the process of plate tectonics.
The rigid outer layer of the Earth, called the lithosphere, is made of plates that fit together like a jigsaw puzzle. These plates are made of rock, but the rock is, in general, lightweight compared with the denser, fluid layer underneath. This allows the plates to "float" on top of the denser material. The fluid dense material is called asthenosphere and in this activity it is represented by the frosting. However, plates are not all the same. Plates made of continental crust are thicker but less dense than plates made of ocean crust, which are denser but thinner. In this activity, ocean plates are represented by fruit roll ups and continental crust is represented by graham crackers.
Movements deep within the Earth, which carry heat from the hot interior to the cooler surface, cause the plates to move very slowly on the surface, about 2 inches per year on average. There are several different hypotheses to explain exactly how these motions allow plates to move.
Interesting things happen at the edges of plates. At divergent plate boundaries, rift valleys and spreading ridges form as plates pull away from each other. At convergent plate boundaries, where plates are coming together, subduction zones form when an oceanic plate and a continental plate collide and mountains build when two continental plates collide. Large faults form when plates slide past each other making the Earth tremble with earthquakes.


http://www.windows.ucar.edu/tour/link=/teacher_resources/teach_snacktectonics.html

The overherds to further help the children undestand the activity are orovided below



#1: Introduction, supplies needed for set-up.


#2: Divergent Plate Boundary


#3: Continent-Ocean Collision


#4: Continent-Continent Collision


#5: Transform Plate Boundary



Activity 2: Pangaea Puzzle

Type of Lesson: Hands-on activity and discussion
Time Needed: 45 minutes, or one full class period
National Standards Addressed
Earth and Space Science, Grades 5-8: The solid earth is layered with a lithosphere; hot, convecting mantle; and dense, metallic core.
Earth and Space Science, Grades 5-8: Lithospheric plates on the scales of continents and oceans constantly move at rates of centimeters per year in response to movements in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, result from these plate motions.
Earth and Space Science, Grades 5-8: Some changes in the solid earth can be described as the “rock cycle.” Old rocks at the earth’s surface weather, forming sediments that are buried, then compacted, heated, and often recrystallized into new rock. Eventually, those new rocks may be brought to the surface by the forces that drive plate motions, and the rock cycle continues.


Quick Summary of LessonThis is a fun, easy way to explain plate tectonics and the various formations of the Earth's surface throughout history. It also shows why maps are distorted.

Materials
potatoes
fine tipped, permanent marker
sharp knife
student activity sheet (optional)

Procedure
1. Each group of two should start with half a potato, cut lengthwise. Now, the students should cut the potatoes into eight pieces.
2. Use the marker to write numbers on the peeling side of each piece.
3. Carefully peel away the white part of the potatoes from each puzzle piece, being sure to leave each piece of peeling in tact.
4. One of the students in the group should mix up the potato pieces and then the other student should put the puzzle back together. Then the 2 partners can switch roles.
5. Have students answer the following questions either in class discussion or have the pairs write their answers down using the Student Activity Sheet in the next section:

• Why don't the pieces fit together correctly? Which is better, a map or a globe, and why?
• Is there any significance to the numbers on each piece? Do they represent something?
• The puzzle is a good representation of the world many years ago. How would it look today? If the pieces move, what causes the movement?
• What are some phenomena that are directly related to the forces which drive the plates?


Notes to the Teacher
The resulting curved pieces will cover a greater flat space than did the hemisphere. This is an excellent illustration of the principle that the only true map is a globe; when you try to place the pieces on a flat surface, they don't fit. Gaps appear between the pieces, and if this were a map, these gaps would represent the map distortions.
Even numbers (2,4,6,8) represent Northern Hemisphere land masses. Odd numbers (1,3,5,7) represent land masses mostly in the Southern Hemisphere. Pieces 2, 4, and 6 represent Laurasia and pieces 3, 1, 5, 8, and 7 represent Gondwanaland.
The crust of the Earth including the continents is made of "plates" which are linked together like a jigsaw puzzle. These solid, but lightweight plates "float" on top of the fluid layer underneath, where the hotter magma is found. And so these plates move about 2 inches per year. Just some of the phenomena associated with the forces that drive the plates are seafloor spreading, subduction, volcanoes, faulting and earthquakes.

http://www.windows.ucar.edu/tour/link=/teacher_resources/pangaea_edu.html


below are the pictures on how to cut the potatoes







Pieces should look like this when the white part is taken off.



Africa
Eurasia
South America
North America
Antarctica
Greenland
Australia
India

http://www.windows.ucar.edu/tour/link=/teacher_resources/potatoes.html

Plate tectonics week 2

In continuation with providing teachers with a resource pack for some backgroud on tectonic plates I have included some information...

What a tectonic plate is

One or more types of tectonic plate activity

the results of the tectonic activity

Project 1: Tectonic Plates

Plate Tectonics

Scientists which are 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.
Deep beneath the waves, at the surface of the ocean, located 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.

http://www.kidsgeo.com/geology-for-kids/0043-plate-tectonics.php

The different plates
It is believed that the crust, beneath the oceans as well as the continents, together with the upper part of the mantle is divided into huge slabs called plates. The movement of the plates is explained by the earlier theory of Continental Drift.
There are eight identified major plates plus an assortment of smaller ones. The major plates include
- the Eurasian plate,
- the African plate,
- the North American plate,
- the South American plate,
- the Antarctic plate,
- the Indoaustralian plate,
- the Pacific plate
- The Nazca plate.






(Fig 1.10) Major plates of the world.

Figure 1.10 the different plates on the world map, which shows that the plates are capped by both the oceanic and continental crust.
http://library.thinkquest.org/17457/platetectonics/3.php

Tectonic plate interaction
There are three different basic types of tectonic plate interactions:
• Divergent boundaries are areas where plates move away from each other, forming either mid-oceanic ridges or rift valleys.




• Convergent boundaries are areas where plates move toward each other and collide. These are also known as compressional or destructive boundaries.
o Subduction zones occur where an oceanic plate meets a continental plate and is pushed underneath it. Subduction zones are marked by oceanic trenches. The descending end of the oceanic plate melts and creates pressure in the mantle, causing volcanoes to form.
o Obduction occurs when the continental plate is pushed under the oceanic plate, but this is unusual as the relative densities of the tectonic plates favours subduction of the oceanic plate. This causes the oceanic plate to buckle and usually results in a new mid ocean ridge forming and turning the obduction into subduction
o Orogenic belts occur where two continental plates collide and push upwards to form large mountain ranges.





• Transform boundaries occur when two plates grind past each other with only limited convergent or divergent activity.






The result of the tectonic activity

Convergent Boundaries
Converge is a large word that scientists use to describe two objects that come together. In the case of plate tectonics, the two objects coming together are large plate-like pieces of the Earth’s crust. As these two plates push against each other, one is ultimately forced down beneath the other.





When this happens near land, we see the earth above the two meeting plates rise, forming spectacular mountain ranges. A parallel oceanic trench typically forms just off the shore, as one plate descends deep into the Earth’s core.
These convergent boundaries commonly cause volcanoes to form, as old crust melts. As two plates rub against one another, a number of small and large earthquakes are common near convergent boundaries.
http://www.kidsgeo.com/geology-for-kids/0046-convergent-boundaries.php

Transform Boundaries

The final type of boundary is one where the two plates slide against each other in a sideways motion. These boundaries between plates is referred to as transform boundaries. As two plates slide past one another, in a transform boundary, neither plate is added to at the boundary, nor destroyed.




The result of two massive plates pushing against one another is that massive amounts of energy build up. Occasionally this energy is released suddenly in the form of large earthquakes.
http://www.kidsgeo.com/geology-for-kids/0047-transform-boundaries.php

Divergent Boundaries

The word diverge is a big word used by scientists to describe what happens when two objects move away from each other. Thus, a divergent boundary is a boundary where two tectonic plates are moving away from one another. As we have already discussed, this most often takes place at ocean ridges.





These ridges are zones of intense volcanic activity. In addition to forming at the bottom of oceans, these divergent boundaries can also form on continents. When this happens, a line of volcanoes emerges.
http://www.kidsgeo.com/geology-for-kids/0045-divergent-boundaries.php

Project 1: tectonic plates

These are some links that I found for kids to have a look at when learning about tectonic plates

http://www.weatherwizkids.com/earthquake1.htm

http://geology.com/nsta/

lesson plans for children

http://www.instructorweb.com/lesson/platesmove.asp