NAME__________________________
CLASS__________________________
DATE__________________________
EASY FLOW - Asthenosphere Lab
I. Problem – How does the rock in the asthenosphere behave? How do the
massive tectonic plates move across the surface of the earth?
II. Hypothesis – We can hypothesize that because the ______________ plates
actually move, that there must be some driving force below them that causes this
motion. It has been theorized that there is a layer within the upper mantle that
permits the tectonic plates to slowly move. This layer within the upper mantle is
known as the ________________________. This layer is believed to be made up
of __________________, ___________________, partially __________________
rock. Floating on top of this layer is the ____________________________ which
consists of the __________________ and the upper portion of the ____________.
We will try and model this plastic-like layer to show how plate motion might be
possible. The word _____________________ is simply a way to say that some
solid materials can actually behave like a fluid.
III. Materials – water, Two 8 oz cups, cornstarch, spoon
IV. Procedures – Prepare simulated asthenosphere as follows:
PART ONE
a) Fill one 8 oz cup ONE-QUATER the way with water, no more
b) Fill second cup half way with cornstarch
c) Use spoon to add one tea-spoon of cornstarch and stir well
d) Continue adding cornstarch 1 spoon full at a time & stir well
e) Stop adding cornstarch when the mixture becomes very hard to stir
PART TWO
f) Examine the mixture by holding it and observing how it flows
g) Observe how the material flowed when allowed to move slowly
h) Also observe how the material flows when forced to move.
V. Safety – This lab can be extremely messy. Please be sure to ___________ up
your lab table when you are finished. The material will not harm you in any way,
so analyze the material closely. Move it in your hands. Press the material
between your palms. “Smoosh” the material on the table and describe its motion.
VI. Data Analysis: - Match up the words at right to their proper places on the
diagram below
A. asthenosphere
B. continental crust
C. lithosphere
D. oceanic crust
1. The material that you
modeled in this lab
represents which of the
four layers shown in
this diagram?
___________________
2. What does lithos
mean in Greek?
___________________
VII. Questions –
1. Define Plasticity - ________________________________________________
______________________________________________________________.
2. Describe how the material behaves when allowed to flow in your hand with no
pressure. ______________________________________________________
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3. Describe how the material flowed when pressure was applied and it was forced
to move. _______________________________________________________
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4. How do geologists believe that the asthenosphere is like the mixture? _______
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
5. Based upon what we have learned about the tectonic plates, do you think that
the mixture is a valid representation of what lies below the lithospheric plates?
Explain your answer? ________________________________________________
_________________________________________________________________
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6. Ultimately, what is the one energy source that drives the tectonic plates? ____
_________________________________________________________________
VIII. Conclusion –
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