Letter | Published:

Magnetic Anomalies over Oceanic Ridges

Nature volume 201, pages 591592 (08 February 1964) | Download Citation

Subjects

Abstract

Vine and Matthews1 suggest that the pattern of local magnetic anomalies on the flanks of a mid-oceanic ridge is strongly lineated parallel to the ridge, and that these magnetic ‘stripes’ represent strips of material in the upper mantle the directions of permanent magnetization of which are alternately parallel and anti-parallel to the present local geomagnetic field. Vine and Matthews suggest that mantle material cools as it rises convectively under a ridge and then spreads2 horizontally outward. As the material cools through its Curie point it is magnetized parallel to the contemporary local geomagnetic field. Because this field reverses quasi-periodically3,4 with a period 2T, T being of the order of 0.5–1.0 million years, stripes of alternate permanent magnetization are produced the width of which is vT, v being the local horizontal velocity with which material at the surface of the mantle spreads away from the centre of the ridge. The stripes are observed1 to have widths of the order of 20 km. If T is 0.5 million years, v is 4 cm/yr. Convective velocities of this order are also indicated by palæomagnetic data5.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    , and , Nature, 199, 947 (1963).

  2. 2.

    , Nature, 190, 854 (1961).

  3. 3.

    , Geol. Mag., 91, 352 (1954).

  4. 4.

    , , and , Nature, 198, 1049 (1963).

  5. 5.

    , Geophys. J., 1, 224 (1958).

  6. 6.

    , Continental Drift: A Symposium (Univ. Tasmania, 1958).

  7. 7.

    , , and (in preparation).

  8. 8.

    , Geophys. J., 1, 320 (1958).

  9. 9.

    , , and , Bull. Geol. Soc. Amer., 72, (8), 1251 (1961).

  10. 10.

    , and , J. Geophys. Res. (in the press).

Download references

Author information

Affiliations

  1. Department of Earth Sciences, University of California, La Jolla.

    • GEORGE E. BACKUS

Authors

  1. Search for GEORGE E. BACKUS in:

About this article

Publication history

Published

DOI

https://doi.org/10.1038/201591a0

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.