Download Section 1.1 Outline

1.1 Outline
Earth has several layers
I. Earth is made up of materials
with different densities
1)
Four main layers: inner core,
outer core, mantle, crust
II. Earth’s layers have different
properties
1)
Scientists study how the energy from
earthquakes and underground
explosions travels
A. Core, Mantle, Crust
1)
2)
3)
Inner core: a ball of hot, solid materials,
enormous pressure; remains a solid
Outer core: layer of liquid metals that
surrounds inner core; remains a liquid
due to lower pressure
Mantle: thickest layer (2900 km or 1700
mi); hot rock that is less dense than core;
top part is cool & rigid; below that is hot,
thick paste
A. Core, Mantle, Crust
4)
5)
6)
Crust: thin layer of cool rock; 2 types:
continental (thickest), & oceanic
(thinnest)
Lithosphere: made up of Earth’s crust &
very top of mantle; most rigid of all layers
Asthenosphere: layer of hotter, softer
rock in upper mantle; flows slowly like
hot tar
III. Lithosphere is made up of
many plates
1)
2)
3)
4)
Tectonic plates: large and small slabs of
rock created from the lithosphere
Lithosphere can be compared to the
cracked shell of a hard boiled egg
Most tectonic plates are made up of
BOTH continental and oceanic crust
Two of the most important discoveries in
geology are Earth’s layers and tectonic
plates