22. Anomalies in the Tectonic Evolution of the Pacific

  1. George H. Sutton,
  2. Murli H. Manghnani,
  3. Ralph Moberly and
  4. Ethel U. Mcafee
  1. Edward L. Winterer

Published Online: 17 MAR 2013

DOI: 10.1029/GM019p0269

The Geophysics of the Pacific Ocean Basin and Its Margin

The Geophysics of the Pacific Ocean Basin and Its Margin

How to Cite

Winterer, E. L. (1976) Anomalies in the Tectonic Evolution of the Pacific, in The Geophysics of the Pacific Ocean Basin and Its Margin (eds G. H. Sutton, M. H. Manghnani, R. Moberly and E. U. Mcafee), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM019p0269

Author Information

  1. Scripps Institution of Oceanography, La Jolla, California 92093

Publication History

  1. Published Online: 17 MAR 2013
  2. Published Print: 1 JAN 1976

ISBN Information

Print ISBN: 9780875900193

Online ISBN: 9781118663592

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Keywords:

  • Geophysics—Pacific area—Congresses;
  • Woollard, George Prior, 1908

Summary

Patterns of plate evolution over the past 130 m.y. show an anomalous band of sea floor trending northwest across the central Pacific where large changes in the location and orientation of spreading ridges have been more frequent than elsewhere. In this band regional depths are shallower than expected, and there is a concentration of plateaus, ridges, seamount chains, guyots, atolls, and high islands, some of which contain mildly to strongly alkaline rocks. In this same region spreading rates have been generally higher than elsewhere, commonly exceeding 8 cm/yr, and motions of this part of the Pacific plate relative to the earth's spin axis have been even faster. It is suggested that the high velocities may lead to instabilities in normal plate evolution, expressed as jumping of spreading ridges, and to voluminous mid-plate volcanism.