Geology Reference
In-Depth Information
()Continental collision
a
( ) Island arc-continent collision
b
Passive
continental margin
Continental-
margin orogen
Ocean
i. Precondition
i. Precondition
Intercontinental-
collision orogen
Modified continental-
margin orogen
ii. Collision
ii. Collision
Subduction halted
(island arc subduction?)
()Continent-island arc collision
( ) Island arc collision
c
d
i. Precondition
i. Precondition
Modified passive
continental margin
Compound intra-
oceanic island arc
ii. Collision
ii. Collision
Subduction halted
(island arc subduction?)
Oceanic
crust
Continental
crust
Volcanic
rocks
Figure 4.11
Four kinds of collisional margins. (a) Intercontinental collision orogen formed where two continental plates
collide. An example is the Himalaya. (b) Modified continental-margin orogen formed where an intra-oceanic island arc
moves into a subduction zone bounded by continental crust. (c) Modified passive continental margin formed where a
continent moves towards a subduction zone associated with an intra-oceanic island arc. (d) Compound intra-oceanic
island arc formed by the collision of two intra-oceanic island arcs.
Source:
Adapted from Summerfield (1991, 59-60)
