Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Do you really want to delete this prezi?
Neither you, nor the coeditors you shared it with will be able to recover it again.
Make your likes visible on Facebook?
You can change this under Settings & Account at any time.
Transcript of Tectonic Plates
Alfred Wegner discovered continental drifting. He supported his evidence by looking at the shape of the continents, fossils, matching rock types and geologic structures, and evidence of climate patterns. (A Science Odyssey)
People didn't believe Alfred Wegner's theory when he first explained it because Wegner didn't come up with a way to explain how continents moved. (A Science Odyssey)
After Wegner died, two scientists named Arthur Holmes and Harry Hess kept his idea alive. Holmes says that thermal convection in the earth's mantle could cause continents to move. Holmes also suggested that the continents didn't move but were "carried" by larger pieces of the earth's crust. Hess said that the sea floor was spreading. The sea floor spread causing eroded volcanoes to move with it. (A Science Odyssey)
continental- continental, oceanic- continental, oceanic- oceanic
where crust is destroyed as one plate goes under another.
Ex. Mountains, Volcanoes,
Earth's crust is moving apart
New crust forms
Mid- Ocean Ridges
Plates move horizontally against each other
land pushes together
Ex. Himalayan Mountains
oceanic crust sinks under continental crust
creates trenches. earthquakes, and volcanoes
Ex. Nazca Plate
when two oceanic plates converge, one is subducted under the other.
Ex. The Marianas Trench
The rocks off of the east coast of North America are much older than those right along the mid-Atlantic ridge because sea-floor spreading is occurring where oceanic plates are diverging.
Rocks along the Mid- Atlantic Ridge: several million years old.
Mountains are created by tectonic forces
Land comes together at strong forces and the land crumbles and pushes up to create mountains.
When mountains grow, earthquakes happen. (BBC)
Plate Tectonics Impact Humans' Habitat
1. Earthquakes- many major population centers are located near active fault zones. Earthquakes are caused by moving tectonic plates.
2. Volcanic Eruptions- Volcanic eruptions happen when magma explodes out of volcanoes. Volcanoes destroy and damage many cities and towns.
3. Tsunamis- Major earthquakes occurring along subduction zones are especially dangorous, because they can trigger tsunamis. Tsunamis are huge waves coming in from the ocean to desroy and flood land.
Imagine a giant piece of rock falling out of the sky at a very fast speed. That's what it's like when an asteroid is falling from space. Asteroids create craters from hitting the ground. When an asteroid falls, it gains speed and temperature. The asteroid can get as hot as the Sun, depending on how fast it is falling. The most famous strike was believed to be what killed the dinosaurs. This asteroid hit the ocean and caused one of the most giant tsunamis there ever was. Many of the craters that were once formed have eroded away, but there are still a few that can still be seen today. (BBC)
Rain, wind, sand and ice wear down the Earth's land surface and move the resulting broken down rock and soil to the oceans. This process is called erosion. Weathering helps to cause erosion by breaking down the land. Erosion would transport all the Earth's dry land into the oceans, leaving a water world. It is only the movement of the Earth's plates, which builds mountains, that stops this from happening. Erosion helps to form what our world is today. (BBC)
The Hawaiian Islands are found in the middle of the pacific plate because the ocean floor moves about 5 inches per year. The Hawiian Islands moved with it.
These islands were formed from the hot spot located below the ocean floor.
The upwelling lava creates new volcanic islands that move along with the plate. Hawaii made up a few of these islands.
By: Abby Hiipakka
Rocks on the East coast of North America: hundreds of millions of years old.
(Class Zone) (UWSP)