Abstract
SOLIDITY of the inner core was originally inferred on the basis of the assumption that the inner core has the same composition as the surrounding material of the outer core1. If, however, the observed increase in compressional velocity is related to a compositional change or, as suggested by Elsasser and Isenberg2, to a new phase of iron with rearranged electronic orbits, then the inner core might be liquid3. It was believed that conclusive evidence of solidity of the inner core would come from observations of body waves of the type PKJKP, SKJKS or SKJKP, phases that travel through the inner core as a shear wave. But no reliable observations of these phases have been reported so far.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Birch, F., Amer. J. Sci., 238, 192 (1940).
Elsasser, W. M., and Isenberg, I., Phys. Rev., 76, 469 (1949).
Birch, F., J. Geophys. Res., 57, 227 (1952).
Dziewonski, A. M., and Gilbert, F., Geophys. J. Roy. Astron. Soc. (in the press).
Derr, J., Bull. Seismol. Soc. Amer., 59, 2079 (1969).
Dratler, J., Farrell, W. E., Block, B., and Gilbert, F., Geophys. J. Roy. Astron. Soc. (in the press).
Dziewonski, A. M., Science, 172, 1336 (1971).
Backus, G. E., and Gilbert, F., Geophys. J. Roy. Astron. Soc., 13, 247 (1967).
Kanamori, H., and Press, F., Nature, 226, 330 (1970).
Haddon, R. W., and Bullen, K., Phys. Earth Planet. Interiors, 2, 35 (1969).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
DZIEWONSKI, A., GILBERT, F. Solidity of the Inner Core of the Earth inferred from Normal Mode Observations. Nature 234, 465–466 (1971). https://doi.org/10.1038/234465a0
Received:
Issue Date:
DOI: https://doi.org/10.1038/234465a0
This article is cited by
-
Imaging the top of the Earth’s inner core: a present-day flow model
Scientific Reports (2024)
-
An estimate of absolute shear-wave speed in the Earth’s inner core
Nature Communications (2023)
-
Constraining shear wave velocity and density contrast at the inner core boundary with PKiKP/P amplitude ratio
Journal of Earth Science (2013)
-
Elasticity and rheology of iron above 220 GPa and the nature of the Earth's inner core
Nature (1998)
-
Bulk attenuation in the Earth and viscosity of the core
Nature (1980)
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.