Types of Plate Boundaries
Convergent
Oceanic-Continental
Divergent
Continental
Divergent
Oceanic
Boundary
Name
Sketch of Boundary
Description/Features of Boundary
Examples
Notes
 Lithosphere is lifted and spread apart by convection
currents
 Magma flows into crack and solidifies
 New crust being made at boundary
 Process repeats
Effects
 Sea Floor Spreading
 Submarine mountain ranges
 Earthquakes, volcanic activity
 Widening of ocean basins
Notes
 continental plate arches upward from convection
current and pulls apart to form a rift with faulting
(cracks)
 the blocks slide downward
 streams and rivers fill in to make a linear lake, this
may eventually lead to a new ocean basin
Effects-a rift valley occupied by a linear lake or shallow
arm of the ocean, earthquakes occur along the faults,
volcanic activity sometimes occurs within the rift valley
Notes
 thinner, more dense oceanic plate is overridden by
the thicker, less dense continental plate
(subduction)
 at depths of 100 miles, partial melting begins, magma
chambers form and may rise and break through the
crust to form volcanoes
Effects- earthquakes along the continental margin, ocean
trench offshore, volcanic eruptions inland
Washington-Oregon
coastline-the Juan de
Fuca plate is
subducting under the
N. American plate; the
Cascade Mt. Range is
a line of volcanoes in
the area formed by
the subducting ocean
plate
Andes Mts.-where
the Nazca Plate is
subducting under the
S. American plate
Convergent
Continental-Continental
Convergent
Oceanic-Oceanic
Boundary
Name
Sketch of Boundary
Description/Features of Boundary
Notes
 one oceanic plate will subduct, remelt at depths near
100 miles; magma chambers that are produced may
start to rise and break through the surface to form a
volcano; the cone will be below sea level but may
eventually grow higher; produces an island chain
and in time the islands grow larger and an elongated
landmass is created


Japan,

Eastern
Caribbean
islands of
Martinique
and St. Lucia
Effects- earthquakes, oceanic trench, volcanic islands
Notes
 powerful collision occurs
 deformed rock, folding and faulting of plates 100’s of
miles into the plate
Effects-intense folding, broad folded mountain range,
earthquake activity, shortening and thickening of the
plates in the collision zone
Notes
 two plates slide past one another
 the fracture zone is known as a transform fault
Transform
Examples


Effects-locations of recurring earthquake activity and
faulting, volcanic activity is normally not present
Alpine Fault
of New
Zealand