Crustal Features and Plate Boundaries Notes
Subduction zones -occur where an oceanic plate meets a
continental plate and is pushed underneath it. These zones are
a type of convergent boundary. Ocean plates are denser than
continental plates, so the oceanic plate is pushed under the
continental plate.
Subsidence- is a lowering in elevation of land. This lower area
usually fills in with
water.
**LAND FEATURES….
Trench – a deep depression of the sea floor caused by the
subduction of one plate under another (convergent)
Rift Zones – a large valley shaped area of the earth in which plates
of the earth's crust are moving away from each other, forming a
system of cracks and faults (divergent)
Oceanic Ridges – underwater mountain ranges where the crust is
spreading creating new ocean floor (divergent)
Underwater Mountain Ranges – long, continuous volcanic chain of
various mountain ranges (divergent) rising from the ocean floor
Mountain Ranges on Land – a series or chain of mountains that are
close together and rise 300 m (1,000 ft.) above its surrounding area
(convergent)
Ring of fire – volcanoes that are concentrated on the edges of
continents, along island chains, or beneath the sea forming long
mountain ranges. More than half of the world's active volcanoes
above sea level encircle the Pacific Ocean to form the "Ring of
Fire." (convergent)
Fault- a break in the rocks that make up the Earth’s crust, this
occurs when two plates move past one another. (transform)