Transcript Earth`s Interior Chapter-1 Section-1

Earth’s Interior
Chapter-1 Section-1
By: Ms. Vigil
Science P-1
9/6/04
Earth’s Interior Chp 1-1
What is the
Science of
Geology?
 Earth’s hard surface is formed of rock
 Geology is the study of the planet Earth
 earth’s landforms are the work of
natural forces that slowly build up
and wear down the land
 The earth looks very different than
it did thousands of years ago.
Earth’s Interior Chp 1-1
What are
Surface
Changes?
 Constructive forces: shape the surface
by building up mountains and
landmasses. Example: volcanoes, etc.
 Destructive forces: shape the surface
by slowly wearing away mountains and
other features. EROSION
 Example: ocean waves,
rain, wind, etc.
 Continents
Earth’s Interior Chp 1-1

Is there
indirect
evidence of 
what’s inside
the Earth?
Geologists cannot observe Earth’s
interior directly via seismic waves
It is over 6,000 kilometers from the
surface to the center of the Earth
 Seismic Activity –when earthquakes
occur they produce seismic waves
 Seismic waves travel through the
earth—the speed of the seismic
waves and the paths they take
reveal how the planet is put
together
Earth’s Interior Chp 1-1
 At first as you descend it
becomes cool, however,
What is
Temperature
in the Center  20 meters + rock is getting
of the Earth
warmer
like?
 For every 40 m descended, the
temperature rises 1 degrees
celsius
Earth’s Interior Chp 1-1
 Pressure is the force pushing
on a surface area
What is
Pressure in
the Center of  The deeper you go, the
greater the pressure
the Earth like?
 Three main layers in the Earth
 Crust
 Mantle
 Core
Earth’s Interior Chp 1-1
 The layer of rock that forms
What is Earth’s outer skin
the
Crust?
 Mountains, rocks, soil & water make-up the
surface
 Ranges from 5 to 40 kilometers
 The crust includes both oceanic
crust and continental crust
 Basalt –type of rock that is dark
and dense with a fine texture –
is found primarily on the ocean floor
 Granite – type of rock that has large
crystals and is light in color and is
found primarily on the land
Earth’s Interior Chp 1-1
What is 

the
Mantle 
A layer of hot rock
Made of two parts major parts at the
uppermost part of the Mantle:
Lithosphere and Asthenosphere
 Lithosphere
 Uppermost part of the mantle and
lower part of crust which together
form a rigid layer approx.
200 km thick
 Lithos means stone
 Asthenosphere
 Below the lithosphere
 Soft like tar—it can bend like plastic
Earth’s Interior Chp 1-1
What is
the
core?
 The core consists of two parts: Liquid Outer Core
and a Solid Inner Core
 Outer Core:
 Layer of molten metal that
surrounds the inner core
–like a thick liquid
 Inner Core
 Is a dense ball of solid metal
 Extreme pressure squeezes the atoms of iron
and nickel into a tight solid that can’t become a
liquid
Earth’s Interior Chp 1-1
How does the  Currents in the liquid outer core
force the solid inner core to spin
Earth’s
at a slightly faster rate than the rest
Magnetic
of the planet
Field Work
 These currents in the outer core
creates Earth’s magnetic field—
causes the earth to act like a
gigantic bar magnet
Earth’s Interior Chp 1-1
Exploring
Earth’s
Interior
pg. 22-23
 Complete project
 Scientific drawings of the
Earth’s Interior p.22 and a
Cross section from Earth’s
surface to the center –pg 23.
(These drawings are to be taped or glued into
the Science journal)
Summarize: HOMEWORK








Geology
Constructive & Destructive Forces
Seismic waves
Temp & Pressure in Earth
Crust
Mantle
Core
Earth’s magnetic field