Standard 7a Notes Describe how matter and energy are cycled within earth’s systems: 1.Identify the...
-
Upload
miles-gibbs -
Category
Documents
-
view
216 -
download
1
Transcript of Standard 7a Notes Describe how matter and energy are cycled within earth’s systems: 1.Identify the...
Standard 7a Notes
Describe how matter and energy are cycled within earth’s systems:
1. Identify the energy source and process that moves plate tectonics.
2. Identify and predict how plate tectonics, glacial movement, weather and volcanic activity shape earth’s crust; past, present, and future.
Evidence for Plate Movement
– Current continents appear to fit together Abraham Ortelius – Floods pushed them away
Alfred Weneger – Continental Drift & “Pangea”– Fossils similar on different continents -
Mesosaurus and Glossopteris (plant)– Rock formations: rocks from Appalachian
Mountains similar to Greenland.– Climate: Evidence of large glaciers in warm
climates - Must have all been near a pole at one point
Evidence for Continental Drift (Today)
• We can add…– Seafloor Spreading– Volcanic Activity– Mountain building– Earthquakes near plate boundaries– GPS Movement
Continental DriftNow
Billions of years ago
Plate Tectonics
• Theory of Plate Tectonics – Earth’s lithosphere is divided up into enormous slabs called tectonic plates that are constantly in motion relative to each other.
Earth’s Current Plates
What is next?
Causes for plate movement
• Convection – the movement of hot liquids
1. Matter is heated, it expands and becomes less dense, therefore lighter.
2. Lighter (hotter) material then floats to the top and cooler material sinks to the bottom.
Hot = YellowCool = BlueLook for circular movement!
Where does the heat come from?
• Radioactivity – Unstable isotopes (atoms with too many or too few neutrons) split apart to create energy
• Remaining thermal energy created from the collision of fast-moving, massive objects during the formation of the earth
• Where else does earth get energy?• SUN: (Affects atmosphere more than the
earth’s interior)