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USGS · 70001297

Ophiolites and oceanic crust

E.M. Moores·E.D. Jackson
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Abstract

OPHIOLITES consist of a pseudostratiform sequence, of harzburgite, tectonite, ultramafic and mafic cumulates sometimes including gabbro and quartz diorite (plagiogranite) intrusions, dolerite dyke swarms, pillow lava 1, and deep-sea sediments2-4. This assemblage occurs in all Phanerozoic mountain systems and is interpreted as fossil oceanic crust and uppermost mantle5-10. Outstanding problems include differences between the chemical properties of Ophiolites and rocks thought to represent present-day oceanic crust11,12, the lack in some complexes of recognised dyke swarms or cumulates, and the relative thinness of ophiolite mafic rocks compared with standard oceanic crustal sections5,8,13.

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E.M. Moores, E.D. Jackson. 1974. Ophiolites and oceanic crust. https://doi.org/10.1038/250136a0

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