25 terms

Geological Oceanography (Ch 3) - Plate Tectonics, Continental Drift

the solid part of the earth consisting of the crust and outer mantle
Oceanic Crust
made of mostly basalt; about 5 - 11km thick; denser then continental crust.
Continental Crust
Made up mostly granite; about 35 km thick; less dense then oceanic crust.
Theory of Continental Drift
proposed by Alfred Wegner and Frank B. Taylor, that the continents were once joined together and have since drifted apart
Seafloor spreading
The process that creates new sea floor as plates move away from each other at the mid-ocean ridges
Subduction Zone
is an area on Earth where two tectonic plates meet and move towards one another, with one sliding underneath the other and moving down into the mantle
Divergent Plate Boundary
where two plates are moving apart, magma comes up to create new crust.
Divergent Plate Boundary
Mid-Atlantic Ridge, East Pacific Rise, Pacific-Antarctic Ridge, East African Rift are all examples of ________________
Oceanic Trench
Deep linear depression in the ocean floor where subduction is taking place.
credited with the theory of Continental Drift
credited with the theory of plate tectonics
large pieces of earths crust that move due to convection currents
large supercontinent that existed 250 million years ago
Convergent Boundary
when two plates come together
Mountain Range
formed at a continental-continental convergent boundary
outer layer of the Earth, the thinnest layer
a break in the earths crust that moves
The ocean floor is less than _________ million years old.
Discovered the inner core of the earth
plastic-like layer below the lithosphere
Proposed Seafloor spreading
This scale is used to measure the intensity of earthquakes
Radioactive Decay
The source of the majority of the heat from the inner core
Proposed Unitarianism
Hot spot
A stationary source of heat in the mantle from which a plume rises. Often result in a chain of islands such as the Hawaii islands