The Vourinos ophiolite was thrust on to a SW-dipping sedimentary sequence comprising thick Triassic-Jurassic marbles (platform carbonates) overlain by the late Jurassic Ayios Nicolaos Complex. The sedimentary sequence was deformed and metamorphosed in early Cretaceous times, broadly contemporaneous with ophiolite emplacement. Two facies are identified in different thrust sheets of the Ayios Nicolaos Complex: siltstones and shales with fine tufts occur in the east, while in the west, coarse tufts, cherts and olistostromes are also present. The olistostromes may have developed during the initiation of a subduction zone at the western edge of the carbonate platform. The emplacement of the ophiolite was from the SW, as shown by a Hausen diagram. The oceanic source for the Vourinos ophiolite was probably the same as that for the Pindos and Othris ophiolites, and lay SW of the Pelagonian zone, rather than in the Vardar zone to the NE. It is suggested that the Ayios Nicolaos Complex is essentially a stratigraphic sequence, and not a tectonic mélange as previously described.