Geology Reference
In-Depth Information
A third type of convergent boundary occurs when two plates of continental crust crash
into each other. This is called a
continental-continental convergent boundary.
Figure 9-5:
An
oceanic-oceanic
convergent plate
boundary and as-
sociated geologic
features.
When two plates of continental crust come together, they are each composed
of similar, relatively low density crustal rocks so neither sinks and subducts as
easily as the oceanic crust of other convergent boundaries. Instead, rocks from
each continental plate pile up onto each other, building up tall mountains as the
plates continue to push together. Some crustal material will be forced into the
mantle below, but because of the lighter density of the continental lithosphere,
the crustal rocks resist subduction, resulting in a build-up of crustal material cre-
ating mountains. The features of a continental-continental plate convergence are
illustrated in Figure 9-6.
Figure 9-6:
A
continental-contin-
ental plate conver-
gent boundary and
associated geolo-
gic features.
