Transcript The Geosphere Honors Biology Chapter 3 Definition • The solid part of the earth, including all rock, soil, and sediments • 6378 km radius • Determined by seismic studies Composition • Crust.

The Geosphere
Honors Biology
Chapter 3
Definition
• The solid part of the
earth, including all
rock, soil, and
sediments
• 6378 km radius
• Determined by
seismic studies
Composition
• Crust – 70 km thick;
light elements;
brittle (1% of mass)
• Mantle – 2900 km
thick; medium
density materials;
fluid (64% of mass)
• Core – 3400 km
radius; densest
metals (35% of
mass)
5 Layer Structure
• Lithosphere –
15-300km; cool
and rigid; crust
and upper
mantle; divided
into the
tectonic plates
5 Layer Structure
• Asthenosphere250km; plastic
layer that can
flex and allows
plates to move
on it
5 Layer Structure
• Mesosphere –
2550km; lower
mantle
5 Layer Structure
• Outer core –
2200km; liquid
nickel and iron
5 Layer Structure
• Inner core –
1228 km radius;
solid nickel and
iron
Plate Tectonics
• Internal forces move plates
• Divergent, convergent, and transform fault
boundaries
• Causes mountain building, seafloor
spreading (below), earthquakes and
volcanism
Mountain Building
Earthquakes
• Fault – crack along which movement occurs
• Quake – vibrations from movement
• Magnitude – amount of energy released,
measured by Richter Scale (2.0 felt and 9.5
largest measured); 7.0 is 31.7 times more
energy than 6.0
• Majority occur on crustal plate boundaries
Volcanoes
• Mountain built from
magma/lava
• Often near tectonic
plate boundaries that
are separating or
colliding
• Occur on land and
under the sea
Erosion of the Geosphere
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Removal and transport of materials
Removable because of weathering
Smooths and rounds features
Done by numerous agents: wind,
water, gravity
The Wai'anae and Ko'olau mountain ranges no
longer have rounded tops. They are two extinct
jagged mountain ranges that have been cut
into by streams and rain washing away rocks
and dirt. This is called erosion.
The End (for now)