Transcript Today`s Warm-Up Friday, January 10

Today’s Warm-Up
Friday, January 10
• Write What You Know! Write as much as you
can for five minutes on the prompt below, try for
at least 3-4 complete sentences.
• Astronomy Throwback! Do other planets in our
solar system also have layered atmospheres
and layered interiors like the Earth does? Why?
Why is the Earth’s core made of metal, and the
mantle and crust made of different types of
rock? Why isn’t everything the same inside the
planet?
Earth’s Interior
Section 1.1
Exploring Inside Earth
• How do we know about the Earth’s interior
structure?
• Direct Evidence: Rock Samples
– From drilling, volcanoes, and tectonic movement
• Indirect Evidence: Seismic Waves
– Energy waves from earthquakes, change path and
speed as they move through the Earth. Why?
– Waves travel differently through different materials
Journey to the Center of the Earth
• As you go deeper into the
Earth . . .
– Temperature increases, it
gets hotter!
– Pressure increases
– Material becomes more
dense
– Materials change from
lighter rock to heavier rock
to metal
– Lots of water trapped inside
Earth!
Crust
• Crust is solid, rigid rock
– Breaks under pressure
– Broken into many tectonic plates
Crust
• How far down have we
gone?
– Deepest bore hole (drill)
12 km down
– Deepest cave discovered
3 km down
– Border between crust and
mantle
• 5 km average oceanic crust
• 70 km average under
mountains
Mantle
Rock samples from:
- Volcanic eruptions
- NOT DRILLING!
• Lithosphere: solid, rigid, tectonic plates
(crust and upper mantle)
• Asthenosphere: solid, plastic, convection
currents (middle mantle)
• Mesosphere: solid, rigid (lower mantle)
Core
• Outer Core: liquid metal (nickel & iron)
• Inner Core: solid metal (nickel & iron)
• Why is Inner Core solid not liquid?
– PRESSURE!
Magnetic Field
Magnetic Field
• The Earth rotates to the east
– Outer core rotates west, inner core rotates east, in the
opposite direction!
– Speed of core’s rotation is faster than the planets, and
changes over time!
• This generates our magnetic field, or
magnetosphere
– Protects us against solar wind! Creates auroras at the
poles!
– What would happen if the entire core cooled down
into solid metal and stopped rotating?