Bell Ringer What is one piece of evidence that supported the theory of Continental Drift?

Agenda Notes: Earth’s Layers Independent Work: Slice of Earth Picture Pass out Progress Reports

Earth’s Layers

Layers of the Earth The Earth is made up of three major layers and several sublayers

Layers of the Earth – Crust Crust – thin, solid layer of rock, creating Earth’s surface Coolest layer, with temperatures increasing towards the center of the Earth

Layers of the Earth – Crust Two types of crust: Continental crust – thick (~25km) crust found on the continents Oceanic crust – thin (~7km), dense crust found beneath the oceans

Layers of the Earth – Mantle Mantle – consists of both solid and molten rock mantle

Layers of the Earth – Mantle Lithosphere – the crust and the solid uppermost part of the mantle Asthenosphere – partially-molten layer directly under the lithosphere; slowly flows and causes the land above it to also move solid “lithosphere” floating on top Partially-molten “asthenosphere” underneath

Layers of the Earth – Mantle So, the continental and oceanic crusts float on the asthenosphere Isostasy – the displacement (moving out of the way) of the mantle by Earth’s crust

Layers of the Earth – Mantle The crust is in balance with the mantle, so as the crust’s surface changes, so do its roots (underground parts) As mountains erode away, the mountain roots rise to stay in balance This is called isostatic rebound

Layers of the Earth – Mantle

Layers of the Earth -- Core Core – innermost layer of the Earth Outer Core – liquid iron and nickel Inner Core – solid iron and nickel outer core: liquid inner core: solid

Summary of Earth’s Layers Earth Layer Sub Layer Solid or Liquid? Location Crust Lithosphere Solid Earth’s surface Mantle Below the crust Liquid Below the solid mantle Core Outside the inner core Earth’s center Lithosphere Asthenosphere Outer Core Liquid Inner Core Solid

Summary of Earth’s Layers Inner Core Outer Core Mantle Crust Asthenosphere Lithosphere

Convection The core is much hotter than the crust, which creates convection currents in the asthenosphere Convection – the flow of heated matter rising and cooled matter sinking “Warm up, cool down”

Convection The mantle is heated by the core, and the heated material rises to the crust The mantle is then cooled by the crust, and the cooled material sinks back down towards the core

Convection This keeps the matter in the mantle constantly circulating This circulation due to convection is the driving force of plate tectonics

Earth’s Layers Follow directions carefully. If you need help, then just ask me. You may listen to music while working. This is individual work. Those “collaborating” will split your grade. Turn in when done. I will pass out progress reports while you are working, IF YOU ARE MISSING ANY ASSIGNMENTS AND WOULD LIKE A COPY, WRITE YOUR NAME AND THE ASSIGNMENT(S) ON A PIECE OF PAPER AND I WILL GIVE THEM TO YOU TOMORROW.

Mr. Lee’s Rap: http://www.youtube.com/watch?v=RiHRI_Z2Kgs

Pangaea, Earth’s Layers, and Plate Tectonics http://ed.ted.com/lessons/the-pangaea-pop-up-michael-molina (0-3:00)