"Obduction" is also used in reference to
autopsy.Obduction is the overthrusting of
continental crust by
oceanic crust or
mantle rocks at a
destructive plate boundary. It can occur during an
orogeny.Obduction occurs where a fragment of continental
crust is caught with resulting overthrusting of oceanic
mafic and ultramafic rocks from the mantle onto the continental crust. Obduction often occurs where a small
tectonic plate is caught between two larger plates with the crust, both
island arc and oceanic, becoming attached as a new terraine to an adjacent
continent. When two continental plates collide obduction of the oceanic crust between is often a part of the resulting
orogeny, or mountain building episode.
New Caledonia is one example of recent obduction. The
Klamath Mountains of northern
California contain several obducted oceanic slabs. Obducted fragments also are found in
Oman,
Cyprus,
Newfoundland,
New Zealand, the
Alps of Europe, and the
Appalachians of eastern
North America. The characteristic rocks of the obducted oceanic crust are the
ophiolites; consisting of
basalt,
gabbro,
peridotite,
dunite, and
eclogite. There are many examples of oceanic crustal rocks and deeper mantle rocks that have been obducted and exposed at the surface worldwide.
See more at Wikipedia.org...
Free Download Now!
