Analyzing Continental Data
Provide 4 DIFFERENT examples of fossils.
skeletons, burrows, footprints, body parts (shells)
What is a giant continuous mountain range on the ocean floor called?
Mid-ocean ridge
What are tectonic plates?
The pieces of earth's broken crust that contain earth's entire surface (ocean and continents).
Provide an example of a sudden event caused by plate motion.
What is a continental shelf?
the edge of a continent that is underwater.
What are fossils?
Traces or remains of organisms that lived long ago.
What term refers to the creation of sea floor?
sea-floor spreading
What forms when two plates move away from each other?
volcanoes, mid-ocean ridges, ocean basins
Define plate tectonics.
The theory that describes how Earth's outer layer is broken up into moving tectonic plates explain how earth's surface is shaped
What is a deep-ocean trench?
the deepest valleys on Earth's surface
What observations have been made about Africa and South America?
Continents looked as if they fit together. rocks and fossils of the same plants/animals of the same age in different locations.
Where (in relation to the mid ocean ridge) can the oldest rock on the ocean floor be found?
Farthest away from the ridge
What forms where two plates move towards each other?
volcanoes, mountain ranges
What evidence is there to support plate tectonics?
matching fossils and landforms on different continents, sea-floor spreading, GPS instruments.
How fast do tectonic plates move?
A few cm a year
What important clues do fossils give us?
Information about past environments.
New ocean floor forms at a ________________ and recycles at a __________________ where it sinks back into earth's interior.
Mid ocean ridge; deep ocean trench
Which direction of plate movement does NOT form volcanoes? What features do form here?
Horizontally; hills, mountains, and off-set streams
What drives temperature and density differences in Earth's interior
Energy from deep within Earth
What is the different between a mid-ocean ridge and deep ocean trench?
Mid ocean ridge is where new floor forms and spreads deep ocean trench is where it recycles back into earth's interior
What evidence to scientists have to support the conclusion that mountain ranges on different continents formed at the same time in the same location? (2)
Many of the rocks are the same age and many of the rocks are made up of the same materials.
Explain the process of sea-floor spreading
Heat from deep within the earth rises - stretches the crust apart - stretching forms rift valley - earthquakes and volcanic eruptions occur - eruptions add new rock - forces continue and valley widens
What was the name of our most recent supercontinent?
Pangaea
Describe convection currents in regards to the cycle of rocks.
Energy creates temp and density difference - gravity pulls down on material - creates slow slow cycle for solid interior. (New rock forms at the ridge - gravity pulls on it eventually makes it to trench - falls back into interior to start over)
Explain how GPS instruments and studies of Earth's fossils, landforms, and ocean floor provide evidence for plate tectonics.
Fossils - same fossils same age different continent
Landforms - mountains of the same rock and same age but different continent
Continental shelves fit together
GPS measure plate speeds and directions.