Transcript Earth Layer`s PPT

The
Earth’s
Layers
Earth’s Layers
• Each layer of the Earth has its own unique
properties.
• There are three distinct layers – the crust,
mantle, and core – which can then be
subdivided into more layers.
• Each layer is made up of specific
elements.
Simple Layers
• Crust
• Mantle
• Core
Into the Earth…
The Crust
• Outermost layer
• Thinnest layer and
much cooler than
others
• 2 types of crust
1. Oceanic (very
dense, made of
basalt)
2. Continental (less
dense, made of
granite)
Oceanic and Continental Crust
Thinnest beneath ocean and thickest beneath
mountain ranges
The Mantle
•
•
•
•
Layer beneath crust
Middle layer
Very thick layer
Made up of more
iron and magnesium
so is very dense
• Convection currents
occur in the mantle
Mantle Is Divided into …
Lithosphere
• Consists of the crust and
the upper part of the
mantle
• Solid and rocky
• Broken into large pieces
called tectonic plates
• Earthquakes can occur in
the lithosphere
• Made up of elements
Oxygen and Silicon
Asthenosphere
• Beneath the lithosphere
• Partially molten
• The rock is pliable or
plastic-like
• Rock here bends,
stretches, and flows
• The tectonic plates float
on this layer
Tectonic Plates
• Earth’s crust is broken into about a dozen
major plates and several minor plates
• These plates constantly move on top of
the Asthenosphere
The Core
• Made up of the elements iron and nickel
• 1/3 of the Earth’s mass
• The core is larger
than Mars!
• The core is very
hot and dense
The Core is Divided Into…
Outer Core
Inner Core
• The outer core is a
liquid
• The material of the
outer core is
considered molten as it
is extremely hot
• Less dense than the
inner core
• Made up of Iron and
Nickel
• The inner core is the
most dense
• It is solid even though
the temperature is very
hot due to the extreme
pressure
• The inner core is
composed mostly of
Iron
Earth’s Layers
• How are the Earth’s
layers similar to an
egg?
• Shell=crust
• Egg white=mantle
• Yolk=core
Physical Structure of the Earth
Layers Reviewed
• Crust and Lithosphere- rigid outer layer
• Mantle and Asthenosphere- solid rock that
flows slowly (like hot asphalt)
• Outer Core- liquid layer
• Inner Core- solid, very dense
References
• http://geomaps.wr.usgs.gov/parks/pltec/#c
rust
• http://pubs.usgs.gov/gip/dynamic/dynamic.
html