Shared Flashcard Set

Details

Lesson 8
terms
12
Geology
Undergraduate 4
10/19/2009

Additional Geology Flashcards

 


 

Cards

Term
continental drift
Definition
The motion of continents across ocean basins.
Term
Pangaea
Definition
Wegener's ancient supercontinent formed from the assembly of most of Earth's continental landmasses some 200-300 million years ago.
Term
geosyncline
Definition
A long and narrow portion of Earth's crust that has subsided deeply and filled with sediment.
Term
sea-floor spreading
Definition
The spreading of the sea floor outward from long submarine mountain ranges--the spreading ridges.
Term
apparent polar wander curves
Definition
Changes in Earth's apparent poles through time; plotting the apparent north pole using paleomagnetic inclination and declination measurements in different ages of rocks form one location yeilds different positions for the magnetic pole.
Term
flood basalts
Definition
Huge outpourings of basalt that are believed to be a result of large-scale melting of the upper mantle due to rising mantle plumes immediately prior to continental break-up.
Term
mantle plumes
Definition
A localized zone of upwelling hot mantle. These plumes give rist to hot spots, which are places of abnormally high heat flow.
Term
hot spots
Definition
Regions of unusually high heat flow due to upwelling within the mantle.
Term
active continental margin
Definition
A continental margin that is also a plate margin, either represented by a subduction zone or a transform fault.
Term
passive continental margin
Definition
The edge of a continent, corresponding to the junction between continental and oceanic crust where it occurs in the interior of a plate rather than at a plate boundary.
Term
triple junction
Definition
The junction between three plates.
Term
aseismic creep
Definition
Motion along a fault that does not cause earthquakes.
Supporting users have an ad free experience!