Transcript Bell Work: 10/13/09

10/23/14
Real-Life Rocks

What makes the sun have strong gravitational pull?
 The gravitational pull of an object is determined by how massive (or big) the
object is and how far away fro it you are. The sun is more massive than
Earth, so it has a stronger gravitational pull.
Journey to the Center of the
Earth by Jules Verne
Objectives
26. Earth’s Layers (2 pages)
Differentiate
among the characteristics of the earth’s
three layers. (SPI 0707.7.4)
○ What are the three main layers of the Earth based on
chemical composition?
○ What are the five main physical layers of the Earth?
○ What’s the difference between the chemical and physical
layers?
Recognize
that lithospheric plates on the scale of
continents and oceans continually move at rates of
centimeters per year. (SPI 0707.7.5)
○ Where are the lithospheric plates and how much do they
move a year?
Question…
Can anyone connect our unit on Rocks &
Minerals to this new unit on Earth?
Why?

First, by studying how the Earth worked in the past, we can
better understand how it is working today. This helps us
understand our effects on the environment and its potential
effects on us. For example, by understanding where
earthquakes have occurred in the past, we have a much
better idea of where they are likely to occur in the future and
can be prepared for them. Second, by gaining an
understanding of how Earth works, we can better predict
how the Earth will react to changes. For example, if we
understand how the Earth and its life responded to
temperature changes in the past, we might better understand
the effects of the global warming that is happening today.

So the basic point is to better understand our world. This
helps us to better coexist with nature and reap the benefits
that it has to offer.
1-minute Journal
 Write
a 1-minute journal on how a
peach is like the earth’s layers.
Chemical Composition:
The Four Layers
The Earth is composed of
four different layers. The
crust is the layer that you
live on, and it is the most
widely studied and
understood. The mantle is
much hotter and has the
ability to flow. The outer
core and inner core are
even hotter with pressures
so great you would be
squeezed into a ball smaller
than a marble if you were
able to go to the center of
the Earth!
The Earth's Crust is like the skin of a peach. It is
very thin in comparison to the other three layers.
•The most common rock in the crust is _________________.
basalt
The Earth's Mantle is like the thick, fleshy
inside of a peach. It is the thickest of the
three layers.
The Earth's outer core is like the juice of the peach. It is so hot that the metals in the
outer core are all in the liquid state. The inner core is like the pit of a peach. The
insane pressures at the center cause the inner parts to stay solid.
Teach the layers of the Earth to your elbow
partner. Take turns and be good
listeners!
Create an ACCURATE drawing the earth’s
layers.
You have 5 minutes!
Physical Structure: L.A.M.


The physical structure of the Earth
describes how the earth moves and
responds to temperatures and
pressure.
The three physical structures:
1. Lithosphere
2. Asthenosphere
3. Mesosphere
Lithosphere
The crust and the upper layer of the
mantle together make up a zone of
rigid, brittle rock called the Lithosphere.
Tectonic Plates are pieces
of the lithosphere that
move around on top of the
asthenosphere.
at centimeters per year.
Asthenosphere
The Asthenosphere is the
plastic or viscous layer (solid
that flows) of the mantle on
which pieces of the
lithosphere move.
This part of the mantle "flows"
because of convection
currents. Convection currents
are caused by the very hot
material at the deepest part of
the mantle rising, then cooling
and sinking again --repeating
this cycle over and over.
Convection Currents
The next time you heat anything
like soup or water in a pan you
can watch the convection
currents move in the liquid.
When the convection currents
flow in the asthenosphere
they also move the crust. The
crust gets a free ride with these
currents, like the cork in this
illustration.
Mesosphere



Beneath the asthenosphere is
the strong, lower part of the
mantle called the
mesosphere.
The mesosphere extends
from the bottom of the
asthenosphere to the Earth's
core.
At a depth of 660 km (410
miles), pressure becomes so
great in the mesosphere that
the mantle can no longer flow
and becomes a solid.
Reflection…