A Model for the Gross Structure, Petrology, and Magnetic Properties of Oceanic Crust
Published:January 01, 1972
F. J. Vine, E. M. Moores, 1972. "A Model for the Gross Structure, Petrology, and Magnetic Properties of Oceanic Crust", Studies in Earth and Space Sciences, R. Shagam, R. B. Hargraves, W. J. Morgan, F. B. Van Houten, C. A. Burk, H. D. Holland, L. C. Hollister
Download citation file:
The model is derived by equating the Troodos igneous massif of southern Cyprus with oceanic crust formed by sea-floor spreading. Comparison of the thicknesses and physical properties of the units of the Troodos massif with those deduced for the oceanic crust by seismic refraction experiments suggests the following correlation: layer 1—sediments; layer 2—pillow lavas and dikes, the lower part being predominantly dikes; layer 3—a layered plutonic complex of gabbros and minor diorites overlain by dikes; layer 4 (upper mantle)—pyroxenites, interpreted as accumulate phases of the gabbroic complex, grading downward into dunites and harzburgites thought to represent depleted mantle.
Despite the fact that the pyroxenites and dunites are as strongly magnetized as the unaltered pillow lavas, the record of reversals of the earth’s magnetic field frozen into the oceanic crust at ridge crests is thought to be written largely within the uppermost 500 m or so of unaltered pillow lavas, the lower pillow lavas and the dikes having been subjected to a greenschist facies metamorphism. The total thickness of the dike and gabbroic complexes may well be inadequate to account for the whole of seismic layer 3, leaving the possibility that the lower crust consists of partially serpentinized peridotite and that the Moho is a transition from partially to unserpentinized peridotite as suggested by Hess.