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An Angus/Argo study of the neovolcanic zone along the East Pacific rise from the Clipperton fracture zone to 12°N

E. Uchupi·W. C. Schwab·Richard D. Ballard·J.L. Cheminee·Jean Francheteau·R. Hekinian·D.K. Blackman·Haraldur Sigurdsson
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Abstract

Still photographs and video images collected along the Neovolcanic Zone of the East Pacific Rise from 10°15′N to 11°53′N show that recent volcanic sheet flows, possibly less than 100 years old, are superimposed on an older sediment-laden pillow terrane. This recent activity is restricted to a narrow zone that crosses two topographic highs at 10°55′N and 11°26′N and diminishes along-axis away from these highs. The association of recent sheet flows with older flows and collapse structures on the overlapping spreading centers at 11°45′N supports the evolutionary model for the occurrence and evolution of overlapping spreading centers by MacDonald and others (1986, 1988).

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E. Uchupi, W. C. Schwab, Richard D. Ballard, J.L. Cheminee, Jean Francheteau, R. Hekinian, D.K. Blackman, Haraldur Sigurdsson. 1988. An Angus/Argo study of the neovolcanic zone along the East Pacific rise from the Clipperton fracture zone to 12°N. https://doi.org/10.1007/bf02326089

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