.png)
.jpeg)
Plate Tectonics Vocabulary
The Theory of continental drift
The theory that continents move around on Earth’s surface and that they were once joined together as a single supercontinent.
Evidences of Continental Drift:
Evidences of Continental Drift:
- Continents puzzle-like fit
- The same fossils found on different continents
- Matching rock layers
- tropical plant fossils found in Antarctica
pangaea
About 300 million years ago, Earth had one massive supercontinent called Pangaea.
theory of plate tectonics
The theory that states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet.
divergent plate boundaries
Occurs when two tectonic plates move away from each other.
Divergent boundaries "Divide."
Divergent boundaries "Divide."
convergent plate boundaries
Occurs when two tectonic plates move towards each other.
Convergent plate boundaries "collide."
Convergent plate boundaries "collide."
transform plate boundaries
Occurs when two tectonic plates slide past each other. Result in fault zones and earthquakes.
Ex. San Andreas fault in California.
Transform plate boundaries "slide."
Transform plate boundaries "slide."
continental-continental convergent plate boundaries
Two continental plates collide. Mountains are formed.
Ex: India and Asia are converging. This results in the, still growing, Himalayan Mts.--like Mt. Everest.
Ex: India and Asia are converging. This results in the, still growing, Himalayan Mts.--like Mt. Everest.
continental-Oceanic convergent plate boundaries
A continental plate and an oceanic plate converging. Results in a subduction zone, volcanoes on the continent, and ocean trenches.
Ex: The Cascade Mts. in the western United States. Some volcanoes here are Mt. St. Helens, Mt. Hood, and Mt. Rainier.
Ex: The Cascade Mts. in the western United States. Some volcanoes here are Mt. St. Helens, Mt. Hood, and Mt. Rainier.
oceanic-oceanic convergent plate boundaries
Two oceanic plates converging. Results in a subduction zone, volcanic island arcs, and ocean trenches.
Ex: The Aleutian Islands in southern Alaska.
Ex: The Aleutian Islands in southern Alaska.
continental-continental divergent plate boundaries
Two continental plates dividing. Results in a rift valley which is the beginning of a new ocean basin.
Ex: Africa is currently splitting apart; East Africa's Great Rift Valley.
oceanic-oceanic divergent plate boundaries
Two oceanic plates dividing. Results in mid-ocean ridges-which are mt. ranges in the middle of oceans.