Sedimentary Facies and Plate Tectonics of Equatorial Pacific.

摘要

Facies patterns of post-Eocene equatorial Pacific pelagic sediments indicate northward motion of the Pacific plate of about 3 cm/year with respect to the earth's spin axis, whereas the age gradient of volcanoes in the Hawaiian chain indicates a northward component of motion of the plate with respect to a hot spot in the subjacent asthenosphere of about 6 cm/year. The discrepancy is ascribed to southward motion of the upper part of the asthenosphere with respect to the spin axis. To examine this possibility more closely, a theoretical isopach map is generated for post-Eocene equatorial sediments, to compare with thicknesses known from drilling and seismic studies. (Modified author abstract)