1. The Dynamic Earth Ch. 3

2. Earth is a system System: a group of parts working together  Which of the following are systems?  A gas tank, air filter, water pump, transmission belt, etc  A car  Heart, arteries, veins, by themselves  Heart, arteries, and veins moving blood around your body NO YES NO YES

3. The Earth as a System The Earth is an integrated system that consists of rock, air, water, and living things that all interact with each other. Divided into 4 parts… which?  Geosphere (rock)  Atmosphere (air)  Hydrosphere (water)  Biosphere (living things)

4. Geosphere  The solid part of the Earth that consists of all rock, and the soils and sediments on Earth’s surface.  The name for the solid earth  Made up of layers  Core 3,425 km radius  Hot, iron & nickel  Mantle 2,900 km thick  Dense, can flow  Crust 5-70 km thick  brittle.

5. Lithosphere  This is the rigid outer layer of the earth, consisting of crust and the top part of the mantle.  It is divided into pieces called tectonic plates

6. Asthenosphere  Layer beneath the lithosphere  Solid layer of the mantle made of rock that flows very slowly and allows tectonic plates to move on top of it

7. Tectonic Plates

8.  Glide across the underlying asthenosphere  Similar to a chunk of ice drifting across a pond  The continents are located on tectonic plates and move around with them  The major tectonic plates include the Pacific, North American, South American, African, Eurasian and Antarctic plates.  Others include: the Cocos plate, Nazca plate, Indian plate, and Australian plate

9. Plate Boundaries  Plates may separate:  Separate from one another  Collide with one another  Slip past one another  Forces produced can cause mountains to form, earthquakes to shake the crust, and volcanoes to erupt

10. Himalaya’s  Began to form when the Asia and Indian plates began to collide 50 million years ago.  Still growing today

11. Earthquakes  Fault- a break in the Earth’s crust along which blocks of the crust slide relative to one another  Vibrations of the Earth’s crust caused by slippage along a fault are known as Earthquakes.  Occur all the time, but most can’t be felt

12. Earthquakes  Richter scale  Used to quantify the amount of energy released by an earthquake  Smallest magnitude felt = 2.0  Largest recorded = 9.5  Earthquakes of 7.0 or greater cause widespread damage  8.9 near Japan that led to tsunami

13. Where do Earthquakes occur?  Most occur along or near tectonic plate boundaries  Over the past 15-20 million years, many have occurred along the San Andreas fault, which runs almost the entire length of California  Site where the North American plate and the Pacific plate are slipping past one another

15. Volcanoes  A mountain built from magma (molten rock) that rises from the Earth’s interior to the surface.  Often located near plate boundaries that are either colliding or separating (Pacific Ocean = Ring of Fire)  May occur on land or under the sea which may become islands

17. Global Effects of Volcanic Eruptions  Can change Earth’s climate for several years  Clouds of volcanic ash and sulfur-rich gases may reach the upper atmosphere  Can reduce the amount of sunlight that reaches the Earth’s surface  Can cause a drop in average global surface temperature

18. Erosion  Erosion- the removal and transport of surface material  2 types:  Water erosion  Wind erosion