Chapter 8.2 Flashcards
Seismic Waves
Waves of energy that travel through the Earths crust, caused by earthquakes.
Continental Drift
Movements of the plates of the Earths crust in relation to each other.
Pangea
A super continent that existed about 225 million years ago. All of the landmasses that existed at this time were joined together to form the super continent.
Panthalassa
The vast sea surrounding the super continent of Pangaea.
Crust
The earths crust, which includes landforms, rocks and soil.
Crust material and thickness
Made of mostly solid rock and varies in thickness from 5km under the ocean to 70km under mountain ranges like the Himalayas.
Atmosphere
A blanket of gases that surrounds the earth
Atmosphere height and make up
ATMOSPHERE
At a height of approximately 145km and is mostly made up of nitrogen and oxygen.
What is the mantle made of, its temp, and how thick
MANTLE
- Made of partially molten rock
- Temp mostly between 500-2000 degrees Celsius
- About 2900km thick
What is the outer core made of, its temp and thickness
OUTER CORE
- Made of molten iron and nickel
- Temp between 4000-6000 degrees celsius
- 2300km thick
Hydrosphere
The water on Earth including oceans, lakes, rivers, rain and mist
What is the inner core made of, temp and thickness
INNER CORE
- Mostly iron
- Temperatures up to 7000 degrees celsius
- About 1200km thick
Shrinking Theory
Geologists of the 1800s believed that as the Earth cooled the crust was shrinking and wrinkling. The believed that continents were the high parts of the wrinkles and that the oceans covered the lower parts.
