VUME Upper Mantle of the Earth

Ophiolite Groups and Assemblages.

There are follow group ophiolites:
- Tethyan ophiolites that occur in the eastern Mediterranean sea area, e.g., Troodos in Cyprus and in the Middle East such as Semail in Oman (Tethys is the name given to the ancient sea that once separated Europe and Africa).
- Cordilleran ophiolites that occur in the mountain belts of western North America (the backbone of the continent).
Tethyan ophiolites consist of relatively complete rock series corresponding to the classic ophiolite assemblage and which have been emplaced onto a passive continental margin.
Cordilleran ophiolites sit on subduction zone accretionary complexes (subduction complexes) and have no association with a passive continental margin (Coast Range ophiolite of California, the Josephine ophiolite of the Klamath Mountains (California, Oregon), and ophiolites in the southern Andes of South America.

Despite their differences in mode of emplacement, both types of ophiolite are exclusively SSZ (Supra-Subduction Zone) in origin.
- Ophiolite assemblages in the Alps and some other collisional mountain belts are not formed during subduction, but rather represent the thinned margin of the continent that forms during rifting and continental drift. This incipient ocean crust remains locked to the continental margin when the ocean basin closes, emplacing the incipient ocean crust into the collision zone.
The age of ophiolite formation is often close to the age of their emplacement into the continental crust.