Download Earth & Layers

Earth & its Layers
Allison Morton
Adv. Earth Science
2ND Period
Earth’s Inside Layers
• Earth has 3 layers in the inside- the crust, mantle,
and core.
• The lightest materials make up the outermost
layer, and densest materials make up the inner
layers. This is because lighter materials tend to
float up, while heavier materials sink.
• Earth’s layers are made of different physical
mixtures of elements. This means that the layers
have different compositions.
• Temperature, pressure, and density are the three
things that increase as you go inside the Earth.
The Crust
• The crust is the outermost layer of the
Earth. It is also the thinnest layer. This
is the rocky layer that we live on.
• Since we live on this layer, we would know
more about it than the others.
• Oxygen and silicon are two of the most
abundant elements found in the Earth’s
crust.
The Mantle
• The mantle is the layer of the Earth
between the crust and the core.
• Compared to the crust, the mantle is
extremely thick and contains most of the
Earth’s mass.
• It makes up 80% of the Earth’s total value.
The Core
• The core is the central part of the Earth
below the mantle.
• The core extends from the bottom of the
mantle to the center of the Earth.
• Since the core is so hot it radiates
a natural heat to the upper layers.
• Earth’s core mainly contains
iron.
Earth’s Structure
The Earth is divided into 5 main physical
layers- the lithosphere, asthenosphere,
mesosphere, outer core, and inner core.
Each of these layers have their own
unique characteristics about themselves.
Lithosphere
The lithosphere is the outermost layer
of Earth. A.K.A “Rock Sphere”
This layer is made of two parts - the crust
and the rigid upper part of the mantle.
The lithosphere is the layer that we walk
on.
The lithosphere is divided into pieces
called tectonic plates.
Plate Tectonics
Plate tectonics- is the theory that the
Earth’s lithosphere is divided into
tectonic plates that move around on
top of the asthenosphere.
Tectonic Plates- are actual pieces of
the lithosphere that moves around on
top of the asthenosphere.
Don’t get the two confused!!!!!
Sea-floor Spreading
Sea-floor spreading is the process by
which new oceanic lithosphere is created,
older materials are moved away from the
mid-ocean ridge.
Sea-floor spreading takes place at midocean ridges. At mid-ocean ridges new
lithosphere is formed.
As the tectonic plates move away from the
mid-ocean ridge, magma rises to fill the gap.
The crust increases in age the farther it is from
the mid-ocean ridge.
The oldest crust in the Atlantic Ocean is found
along the edges of the continents.
Diagram of Sea-floor Spreading
Oldest
Youngest
A
MidAtlantic
Ridge
B
• Where is new rock being made?
– Mid-Atlantic Ridge
• Where is old rock being destroyed?
– Marianas Trench
Asthenosphere
• The asthenosphere is a soft layer of the
mantle on which pieces of the
lithosphere move. A.K.A. “Weak
Sphere”
• This sphere is made of solid rock that
flows very slowly. It flows about the same
rate your fingernails grow.
• Also the asthenosphere contains
convection currents.
Outer Core
• The Earth’s core is divided into 2 partsthe outer core and the inner core.
• The outer core is the liquid layer of the
Earth’s core, that lies beneath the
mantle and surrounds the inner core.
Inner Core
The inner core is the solid, dense center of
our planet that extends from the bottom of the
outer core to the center of the Earth.
The inner core is hotter than the liquid outer
core.
The immense pressure from all of the
Earth’s layers keeps it in a solid state.
The inner core was discovered in 1936.
Works Cited
• Earth Science Textbook
• < www.google.com >
• Recent tests,quzzes,and warm-ups
• Made By: Allison Morton