Snack Snack TectonicsTectonics

Everyone should have:Everyone should have:

• 3 graham crackers3 graham crackers

• 2 - 3in squares of fruit 2 - 3in squares of fruit roll upsroll ups

• a piece of wax paper.a piece of wax paper.

Place a large drop of Place a large drop of frosting on your wax frosting on your wax

paperpaper

Spread into a layer about ½ Spread into a layer about ½ of a centimeter thickof a centimeter thick

• -The frosting in this model represents the -The frosting in this model represents the asthenosphere (the layer in which the asthenosphere (the layer in which the Earth’s plates ride)Earth’s plates ride)

• -The plates in this model are represented -The plates in this model are represented by your fruit roll up because the the by your fruit roll up because the the oceanic crust is thin and dense.oceanic crust is thin and dense.

• -The graham crackers represent the -The graham crackers represent the continental crust which is thick but less continental crust which is thick but less dense.dense.

Place the two squares Place the two squares of fruit roll up of fruit roll up

(oceanic plates) onto (oceanic plates) onto the frosting right the frosting right

next to each other.next to each other.

Press down slowly on Press down slowly on the fruit roll ups the fruit roll ups

(because they are dense (because they are dense and will sink a bit into the and will sink a bit into the asthenosphere)asthenosphere) as you as you

slowly push them apart slowly push them apart about ½ of a about ½ of a centimeter.centimeter.

Notice how the frosting is exposed Notice how the frosting is exposed and pushed up where the plates and pushed up where the plates

are separated? This is how are separated? This is how magma comes to the surface magma comes to the surface where real plates are moving where real plates are moving

apart. When plates begin to pull apart. When plates begin to pull apart at continents, rift valleys apart at continents, rift valleys

are made which can become the are made which can become the bottom of the sea floor if the bottom of the sea floor if the plates continue to pull apart.plates continue to pull apart.

Remove one of the Remove one of the fruit roll ups from fruit roll ups from the frosting (you the frosting (you may eat it if you may eat it if you

wish).wish).

Place one of the graham Place one of the graham cracker halves cracker halves lightlylightly

onto the frosting onto the frosting asthenosphere next to asthenosphere next to the remaining fruit roll the remaining fruit roll

up.up.

The graham cracker The graham cracker represents continental represents continental

crust, which is thicker and crust, which is thicker and less dense than the less dense than the

oceanic crust (fruit roll oceanic crust (fruit roll up). It floats high on the up). It floats high on the asthenosphere so don’t asthenosphere so don’t

push down. push down.

Gently push the continent Gently push the continent (graham cracker) towards (graham cracker) towards the ocean plate (fruit roll the ocean plate (fruit roll up) until the two overlap up) until the two overlap

and the graham cracker is and the graham cracker is on top.on top.

The oceanic plate is subducted below The oceanic plate is subducted below the continental one. the continental one.

Now we need to Now we need to collide two collide two

continents. Remove continents. Remove both the graham both the graham

cracker and the fruit cracker and the fruit roll up (you may eat roll up (you may eat

both).both).

Get two new graham Get two new graham crackers.crackers.

Place one edge of two Place one edge of two graham crackers into a graham crackers into a glass of water for just a glass of water for just a

few seconds.few seconds.

Place the crackers Place the crackers into the frosting with into the frosting with the wet edges next the wet edges next

to each other.to each other.

Slowly push the graham Slowly push the graham crackers towards each crackers towards each

other.other.

Notice how the wet edges Notice how the wet edges crumble? This is how mountains crumble? This is how mountains

are made. When continents are made. When continents move towards each other there is move towards each other there is

nowhere for the rock to go but nowhere for the rock to go but up.up.