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Overlapping spreading centres: new accretion geometry on the East Pacific Rise

Naturevolume 302, pages55–58 (1983)Cite this article

Abstract

In a detailed Seabeam investigation of the East Pacific Rise (EPR) from 8°N to 18°N, a new kind of volcano-tectonic geometry associated with fast-spreading centres has been discovered (Figs 1, 2). At several locations along the rise axis the neovolcanic zone is discontinuous, and is laterally offset a short distance (1–15 km). In contrast to a classic ridge–transform–ridge plate boundary, however, the offset ridge terminations overlap each other by a distance approximately equal to or greater than the offset. They curve sharply towards each other and often merge into one another along strike. Separating the overlapping spreading centres (OSCs) is a closed contour depression up to several hundred metres deep which is sub-parallel to the trend of the OSCs. The region between the OSCs is a complex zone of both shear and rotational deformation with no obvious transform parallel structures. Based on wax model studies of spreading centres, we suggest here that transform faults fail to develop at fast spreading centres where the lateral offsets are small (<15 km), because the lithosphere is too thin and weak to maintain a classic, rigid plate spreading centre–transform fault pattern. The OSC geometry is unstable and evolves rapidly. One of the two OSCs prevails while the other is abandoned. A significant area of sea floor created at fast spreading rates may bear the imprint of this newly observed process.

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References

  1. Glenn, M. F.Int. Hydrogr. Rev.47, 35–39 (1970).

    Google Scholar 

  2. Klitgord, K. D. & Mammerickx, J.J. geophys. Res.87, 6725–6750 (1982).

    Article ADS  Google Scholar 

  3. Lonsdale, P.Mar. geophys. Res.3, 251–293; 295–315 (1977).

    Article  Google Scholar 

  4. RISE TeamScience207, 1421–1433 (1980).

  5. CYAMEXMar. geophys. Res.4, 345–379 (1981).

  6. Rea, D. K.Bull. geol. Soc. Am.89, 836–844 (1978).

    Article  Google Scholar 

  7. Morton, J. & Ballard, R. D.EOS62, 1027 (1981).

    Google Scholar 

  8. Vogt, P. R. & Perry, R. K.Geol. Soc. Amer. May & Chart Ser. 1–21 (1982).

  9. Fleming, H. S. & Phillips, J. D.Geol. Soc. Am. Map Ser. MC-19 (1978).

  10. Orcutt, J. A., Kennett, B. L. N. & Dorman, L. M.Geophys. J. R. astr. Soc.45, 305–320 (1976).

    Article ADS  Google Scholar 

  11. Rosendahl, B. R.et al.J. geophys. Res.81, 5294–5305.

  12. Hale, L. D., Morton, C. J. & Sleep, N. H.J. geophys. Res.(in the press).

  13. Oldenburg, D. W. & Brune, J. N.J. geophys. Res.80, 2575–2585 (1975).

    Article ADS  Google Scholar 

  14. Atwater, T.Deep-Drilling Results in the Atlantic Ocean: Ocean CrustVol.2 (eds Talwani, M., Harrison, C. G. & Hayes, D. E.) 33–42 (American Geophysical Union, Washington, D.C., 1979).

    Book  Google Scholar 

  15. Bryan, W. B. & Moore, J. G.Bull. geol. Soc. Am.88, 556–570 (1977).

    Article CAS  Google Scholar 

  16. Macdonald, K. C.A. Rev. Earth planet. Sci.10, 155–190 (1982).

    Article ADS  Google Scholar 

  17. Ballard, R., Van Andel, J. & Holcomb, R.J. geophys. Res.87, 1149–1161 (1982).

    Article ADS  Google Scholar 

  18. Hey, R., Duennebier, F. & Morgan, W.J. geophys. Res.85, 3647–3658 (1980).

    Article ADS  Google Scholar 

  19. Lonsdale, P.EOS63, 1108 (1982).

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Geological Sciences and Marine Science Institute, University of California at Santa Barbara, California, 93106, USA

    Ken C. Macdonald

  2. Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, 02881, USA

    P. J. Fox

Authors
  1. Ken C. Macdonald
  2. P. J. Fox

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Macdonald, K., Fox, P. Overlapping spreading centres: new accretion geometry on the East Pacific Rise.Nature302, 55–58 (1983). https://doi.org/10.1038/302055a0

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