Abstract
The Lament seamounts form a chain of five volcanoes extending northwestward from the flanks of the East Pacific Rise (EPR) near 10° N (Fig. 1). They have been investigated using Sea MARC I and Sea Beam sonar1 and most recently with the submersible Alvin2. During the most recent field programme we collected precisely located samples from stratigraphic sections on caldera and crater walls of each volcano and from the adjacent EPR. Major objectives of this programme were to determine whether the seamounts and the nearby ridge crest shared common mantle sources and to elucidate off-axis magma storage and ascent processes. The chemical compositions of Lamont seamount lavas, which include some extremely primitive basalts, indicate that each sea-mount was fed from one or more closely spaced mantle sources with depleted chemical characteristics. The geochemical and isotopic data imply that there is no direct magmatic link between Lamont seamount and EPR accretionary magma sources. Lateral distances between individual seamounts, as well as those between the EPR axis and cones at the base of Sasha seamount are small (Fig. 1), leading us to the conclusion that chemical heterogeneities in depleted mantle sources exist on a very small scale (<5 km).
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
Fornari, D. J., Ryan, W. B. F. & Fox, P. J. J. geophys. Res. 89, 11069–11083 (1984).
Seamount Research Group Eos 67, 1184 (1986).
Langmuir, C. H., Bender, J. F. & Batiza, R. Nature 322, 422–429 (1986).
Presnall, D. C. & Hoover, J. D. Geochem. Soc. Spec. Pub. 1, 75–89 (1987).
Zindler, A., Staudigel, H. & Batiza, R. Earth planet. Sci. Lett. 70, 175–195 (1984).
Klein, E., Langmuir, C., Bender, J., Batiza, R. & Zindler, A. Eos 67, 1255 (1986).
Macdougall, J. D. & Lugmair, G. W. Nature 322, 422–430 (1986).
White, W. M., Hofmann, A. W. & Puchelt, H. J. geophys. Res. 92, 4881–4894 (1987).
Hamelin, B., Dupré, B. & Allègre, C. J. Earth planet. Sci. Lett. 67, 340–350 (1984).
Zindler, A. & Hart, S. R. A. Rev. Earth planet. Sci. 14, 493–571 (1986).
Graham, D. W. et al. Contr. Miner. Petrol. (in the press).
Takahashi, E. & Kushiro, I. Am. Miner. 68, 859–879 (1983).
Allan, J. A., Batiza, R., Perfit, M. R., Fornari, D. J. & Sack, R. J. Petrol. (submitted).
Sleep, N. H. J. geophys. Res. (in the press).
Shirey, S. B., Bender, J. F. & Langmuir, C. H. Nature 325, 217–223 (1987).
Thompson, G., Bryan, B., Ballard, R. D., Hamuro, K. & Melson, W. G. Nature 318, 429–433 (1985).
Dupré, B., Lambert, B., Rousseau, D. & Allègre, C. J. Nature 294, 552–554 (1981).
Perfit, M. R., Fornari, D. J., Embley, R. W. & Malahoff, A. J. geophys. Res. 88, 10551–10572 (1983).
Hekinian, R., Thompson, G. & Bideau, D. Monogr. Am. geophys. Un. (in the press).
Hamelin, B., Dupré, B. & Allègre, C. J. Earth planet. Sci. Lett. 76, 288–298 (1986).
Klein, E. M. & Langmuir, C. H. J. geophys. Res. 92, 8089–8115 (1987).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fornari, D., Perfit, M., Allan, J. et al. Small-scale heterogeneities in depleted mantle sources: near-ridge seamount lava geochemistry and implications for mid-ocean-ridge magmatic processes. Nature 331, 511–513 (1988). https://doi.org/10.1038/331511a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/331511a0
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.
