2. Gravity Field of the Northwest Pacific Ocean Basin and Its Margin

  1. George H. Sutton,
  2. Murli H. Manghnani,
  3. Ralph Moberly and
  4. Ethel U. Mcafee
  1. A. B. Watts,
  2. M. Talwani and
  3. J. R. Cochran

Published Online: 17 MAR 2013

DOI: 10.1029/GM019p0017

The Geophysics of the Pacific Ocean Basin and Its Margin

The Geophysics of the Pacific Ocean Basin and Its Margin

How to Cite

Watts, A. B., Talwani, M. and Cochran, J. R. (1976) Gravity Field of the Northwest Pacific Ocean Basin and Its Margin, 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/GM019p0017

Author Information

  1. Lamont-Doherty Geological Observatory And Department Of Geological Sciences, Columbia University, New York, New York 10027

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

Surface-ship and pendulum gravity measurements have been combined in new free-air gravity anomaly maps of parts of the northwest Pacific Ocean basin and its margin. The most prominent features of these maps are the broad belts of positive anomalies which occur seaward of deep-sea trenches and landward of island arcs at the margins of the northwest Pacific basin and the broad belts of positive and negative anomalies which flank the eastern end of the Hawaiian ridge in the interior of the basin. The positive anomalies seaward of trenches can be easily isolated from the longer wavelength regional gravity field of the northwest Pacific upon which they are superimposed. These studies show that (1) positive free-air gravity anomalies of about +40 to +50 mgal occur seaward of trenches and (2) negative residual gravity anomalies of about −10 mgal occur over the Pacific basin, except over Hawaii and the Gulf of Alaska where they are positive.