Unit 1 Flashcards
Continental Drift Theory was proposed when and by who?
In 1912 by Alfred Wegener.
What is the Continental Drift Theory?
200 million years ago the Earth was one giant continent called Pangaea which broke apart and formed the continents.
How did Wegener support his theory?
Fossils (nearly identical) on different continents
What is proof of Pangaea?
The shapes match, the plants/animals match, and rocks match.
What are clues from the ocean?
Mid-ocean ridge; sea floor spreading
Why did few people believe in the CDF?
Difficult to conceive large continents could plow through the sea floor to move to new locations.
What causes tectonic plate movement?
The convection currents in the mantle.
What does the theory of plate tectonics state?
The Earth’s outer shell is a series of small and large moving plates.
What is a tectonic plate?
A massive, irregularly shaped slab of solid rock.
What is believed to be the plate-driving force?
The movement of hot, softened mantle that lies below the plates.
What is a divergent boundary?
Spreading apart of tectonic plates. (Created)
What is a convergent boundary?
Pressing together of tectonic plates. (Destroyed)
What is a transform boundary?
Tectonic plates sliding across each other.
What is subduction?
When one plate dives under another.
How do plates affect us?
Earthquakes, tsunamis, and volcanoes (Ring of Fire).
What are the two types of weathering?
Chemical and mechanical.
What is the crust?
Thin, rocky, includes landforms. 4-40 miles thick. Averages 5miles below the oceans, 22 below continents.
What is the mantle?
Thick layer of hot rock, 1800 miles thick. Mostly solid, but pliable rock churns slowly. Draws heat from the center of the earth. Convection causes the plates to move; upper layer may be molten.
What is a representation of the convection of the mantle?
Boiling rice.
What is the outer core?
Molten, churning liquid rock, mostly iron and nickel.
What is the inner core?
Ball of iron 1/3 the size of the moon, boiling hot at 11,000 degrees Fahrenheit.
What is the atmosphere made of?
Air.
What is the hydrosphere made of?
Water.
What is the lithosphere/geosphere made of?
Land.
What is the biosphere made of?
Life.
What does chemical weathering do?
Alters chemical makeup of the substance.
What does mechanical weathering do?
Changes the physical structure of the substance.
What are the two kinds of chemical weathering?
Carbonic acid and acid rain.
What does carbonic acid do?
Can dissolve rock.
What does acid rain do?
Destroys forests and pollutes water.
What are the two kinds of mechanical weathering?
Frost-wedging and root-wedging.
What is frost-wedging?
It is when water freezes in a rock and causes the rock to break.
What is root-wedging?
What plants grow through the cracks of rocks.
What are the three types of erosion?
Wind, water and ice erosion.
How does wind erode?
Wind picks up soil and carries it away. (Ex. The Dust Bowl.)
How does water erode?
The sediment is picked up by water and moves from one location and is deposited in another. (Ex. Cape Hadaras, the Niall River, Mississippi River/The Gulf of Mexico)
How does ice erode?
Glaciers move and carry dirt, rocks and boulders. (Ex. Greenland Glacier, Columbia Glacier. (Alpine Glaciers)
What is erosion?
The movement of weathered material.
