Paleodeclinations of several small seamounts on the northern Cocos plate demonstrate that it rotated approximately 30° counter-clockwise about a pole close to its northern boundary during the past 1 to 6 m.y. Paleoinclinations agree with models of absolute plate motion in which the northern component of velocity for the Cocos plate is about 50 mm/yr. The paleomagnetic data, dredge samples, and seamount morphology, either independently or in concert, are reasonably reliable for distinguishing fault blocks from central volcanoes and for determining the approximate age of a structure relative to that of the surrounding sea floor.

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