The Troodos complex of Cyprus has been interpreted as a slice of oceanic crust formed from ultramafic magma in a back-arc basin. Recent investigations, however, have suggested that only the upper gabbros, the sheeted dike complex, and the lower lava sequence formed as a direct consequence of seafloor spreading and that the primary magma was of basaltic composition. According to this model, the upper lave suite and related ultramafic cumulates are not represented in the sheeted dike complex. A multivariate statistical analysis of major element compositions of 480 dikes and 130 volcanic glasses supports this suggestion. Statistically (98%), the dikes are similar to the glasses of the lower lava suite. This supports the model that the seafloor spreading related sequence of the Troodos ophiolite is relatively thin and of basaltic composition. The magma chambers represented by the ultramafic cumulates and associated gabbros and the upper lavas appear to have been emplaced after, or during, the termination of the major spreading events. ¿ American Geophysical Union 1993