Transcript What creates Earth`s Magnetic Field?

4.1 Reading Notes
1. What prevents
geologists from directly
exploring Earth’s
interior?
• It’s too dangerous
• The conditions are too
extreme
• It’s IMPOSSIBLE
2.Geologists use
direct evidence
Samples
from Rock
__________
to learn about
Earth’s interior.
3. Geologists learn
about Earth’s
interior using
indirect evidence
Seismic waves
from ___________.
4. True or False:
Geologists are able
to drill to the
center of Earth.
False
5. Seismic waves
reveal the structure
of Earth through
Speed
their ___________
paths they travel
and ____________.
Seismic waves
6.________
are produced by
earthquakes.
7. What are the
three main layers
that make up Earth?
Crust
Mantle
Core
8. Which layer
forms Earth’s outer
skin?
The crust
9.Which type of
dark-colored rock
makes up most
the oceanic
crust?
Basalt
10. What is the
name of the lightcolored rock that
makes up most of the
continental crust?
Granite
11. Describe the following:
Lower mantle-
Solid material beneath the asthenosphere
Lithosphere-
A rigid layer- includes upper part of the
mantle and crust
Asthenosphere-
The soft layer below the lithosphere.
Part of the mantle that can bend like plastic.
12. About how many
kilometers thick is
the mantle?
3,000
13. Name two types
of metals that make
up the Earth’s outer
core.
Iron and nickel
14.Describe how a
compass needle
aligns itself.
It aligns itself with the
lines of force in Earth’s
magnetic field.
Direct Evidence- Something
that you can actually hold
in your hand or touch, hear
with your ears or see with
your own eyes.
Indirect Evidence-
Something that you
can’t actually touch,
but you can learn from
its results.
How does the temperature
change from the surface to
the center of the earth?
The temperature remains the same
from the surface to about 20
meters down. After that, the
temperature rises rapidly for many
kilometers.
How does the pressure
change from the surface to
the center of the earth?
The pressure from the weight of
rock increases as you travel from
the crust towards the mantle and
core.
What creates Earth’s
Magnetic Field?
Movements in Earth’s
outer core create Earth’s
Magnetic field.