Plates
How many plate boundaries are there?
three
What is the theory of the continental drift?
The theory that states that the continents used to be connected.
What is subduction?
When one plate dives under another plate
What are the 4 layers of earth in order from outside to inside?
Crust, mantle, outer core, inner core
What are convection currents and how do they help the plates move?
Convection currents are the ability of the asthenosphere to flow. When mantle rocks near the core heat up, they become less dense than the cooler, upper mantle rocks. These warmer rocks rise, while the cooler rocks sink, creating slow, vertical currents. They are the driving force of plate tectonics.
What are the three different plate boundaries?
Divergent, Convergent, Transform
Who proposed the idea of the Continental Drift Theory?
Alfred Wegner
What is convection?
Two plates going towards each other
What property determines how the layer of earth are arranged?
density
What is the theory of continental drift and who proposed the idea?
The theory of continental drift is the theory that the continents used to be connected. Alfred Wegner proposed the idea.
What do divergent plate boundaries do?
They move away from each other, magma rises and forms mid ocean ridges
What are some pieces that support continental drift?
Rocks, Fossils, age of rock, and climate.
Why was the discovery of Mesosaurus Fossils important evidence for continental drift?
Fossils of Reptile Mesosaurus found in South America and Africa. Swimming reptile only lived in freshwater and on land yet found on continents separated by the ocean
Describe the inner core
The innermost layer of the earth & its made iron + nickel
List pieces of evidence for continental drift.
Reptile fossils
Plant fossils
Rocks
Geologic formations
Puzzle like fit
Climate
What do converging plate boundaries do?
Two plates crash into one another and crumple upward, they form a single land mass. They can also collide with ocean plates and plunge downward under a continental plate
Why was the discovery of the Mesosaurus Fossils important evidence for continental drift?
They were found on different continents supporting the continental drift theory.
What is the name of the Super Continent?
Pangea
Describe the Mantle.
The mantle is the thickest layer of the earth and is made of semi-solid molten rock. It is composed of magnesium and iron.
Why is climate important evidence for continental drift?
Fossils of warm weather plants found in the Arctic Ocean on an island. There was glacial evidence in tropical regions, South America, India, Africa, Australia. Scaring shows they were once covered by glaciers
What do transform plate boundaries do?
Two plates can pull away from each other, on land this forms a ridge or separation. Examples is Iceland and how it goes away from two plates.
Why is climate important evidence for the continental drift theory.
There was evidence that plants that live in specific places were in the wrong part of the earth.
What properties determine how layers of the earth are arranged?
Compositional and physical layers
Describe the crust
The crust is the outer layer of the earth, it has two types of crust: Oceanic and Continental. The crust is the thinnest layer of the earth and is solid where life exists. It is composed of mainly oxygen, silicon, aluminum, and small amounts of other elements.
What property determines how the layers of the earth are layered?
Density