Abstract
Both scaled laboratory experiments and numerical models of terrestrial mantle plumes produce ‘balloon-on-a-string’ structures, with a bulbous head followed by a stem-like tail. Discussions have focused on whether their initial upwelling heads are hotter than the tails or cooler, as a result of entrainment of ambient mantle during ascent1,2,3, and also on whether initial plume upwelling is a newtonian or non-newtonian process4,5. The temperature of the mantle delivered to the base of the lithosphere is a critical parameter in such debates. Dry continental magmas can normally contribute little to this topic because their hottest (ultramafic) examples can be expected to be trapped, owing to their density, beneath the Moho. Here we report a rare case in which olivine (with 93.3% forsterite; Mg2SiO4) phenocrysts, precipitated from an unerupted komatiitic melt (∼24% MgO) of the Tristan mantle plume head 132 Myr ago, were carried to upper-crust levels in northwest Namibia by less Mg-rich (9.6–18.5% MgO) magmas. We infer that the hidden melt, generated when the plume impinged on the base of the lithosphere, originated in the mantle with a potential temperature of ∼1,700 °C. This is ∼400 °C above ambient and much hotter than the temperatures previously calculated for steady-state Phanerozoic mantle plumes3,6,7,8. Published data show that the same conclusion can be reached for the initial Iceland and Galapagos plumes.
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
Griffiths, R. W. & Campbell, I. H. Stirring and structure in mantle starting plumes. Earth Planet. Sci. Lett. 99, 66–78 (1990).
Farnetani, C. G. & Richards, M. A. Numerical investigation of the mantle plume initiation model for flood basalt events. J. Geophys. Res. 99, 13813–13833 ( 1994); Thermal entrainment and melting in mantle plumes. Earth Planet. Sci. Lett. 136, 251– 267 (1995).
White, R. S. & McKenzie, D. Mantle plumes and flood basalts. J. Geophys. Res. 100, 17543– 17585 (1995).
van Keken, P. Evolution of starting mantle plumes: a comparison between numerical and laboratory models. Earth Planet. Sci. Lett. 148, 1– 11 (1997).
Larsen, T. B., Yuen, D. A. & Storey, M. Ultrafast mantle plumes and implications for flood basalt volcanism in the North Atlantic Region. Tectonophysics 311, 31–43 (1999).
Watson, S. & McKenzie, D. Melt generation by plumes: a study of Hawaiian volcanism. J. Petrol. 32, 501 –537 (1991).
Ribe, N. M. & Christensen, U. R. The dynamical origin of Hawaiian volcanism. Earth Planet. Sci. Lett. 171, 517–531 (1999).
Shen, Y., Solomon, S. C., Bjarnason, I. Th. & Wolfe, C. J. Seismic evidence for a lower-mantle origin of the Icelandic plume. Nature 395, 62–65 ( 1998).
McKenzie, D. & Bickle, M. J. The volume and composition of melt generated by extension of the lithosphere. J. Petrol. 29, 625–679 (1988).
Gill, R. C. O., Pedersen, A. K. & Larsen, J. G. in Magmatism and the Causes of Continental Break-up (eds Storey, B. C., Alabaster, T. & Pankhurst, R. J.) 335 –348 (Spec. Publ. 68, Geological Society, London, 1992).
Nisbet, E. G., Cheadle, M. J., Arndt, N. T. & Bickle, M. J. Constraining the potential temperature of the Archaean mantle: a review of the evidence from komatiites. Lithos 30, 291–307 (1993).
Echeverria, L. M. & Aitken, B. G. Pyroclastic rocks: another manifestation of ultramafic volcanism on Gorgona island, Colombia. Contrib. Mineral. Petrol. 92, 428– 436 (1986).
Francis, D. The Baffin Bay lavas and the value of picrites as analogues of primary magmas. Contrib. Mineral. Petrol. 89, 144– 154 (1985).
Le Bas, M. J. IUGS reclassification of the high-Mg and picritic volcanic rocks. J. Petrol. (in the press).
Duncan, A. R., Armstrong, R. A., Erlank, A. J., Marsh, J. S. & Watkins, R. T. in Mafic Dykes and Emplacement Mechanisms (eds Parker, A. J., Rickwood, P. C. & Tucker, D. H.) 119–129 (Balkema, Rotterdam, 1990).
Schmitt, A. K., Emmermann, R., Trumbull, R. B., Bühn, B. & Henjes-Kunst, F. Petrogenesis and 40Ar/39Ar geochronology of the Brandberg complex, Namibia: evidence for a major mantle contribution in metaluminous and peralkaline granites. J. Petrol. 41, 1207–1239 (2000).
Libourel, G. Systematics of calcium partitioning between olivine and silicate melt: implications for melt structure and calcium content of magmatic olivines. Contrib. Mineral. Petrol. 136, 63–80 (1999).
Li, J.-P., O'Neill, H. St C. & Seifert, F. Subsolidus phase relations in the system MgO-SiO 2-Cr-O in equilibrium with metallic Cr, and their significance for the petrochemistry of chromium. J. Petrol. 36, 107–132 (1995).
Ulmer, P. The dependence of the Fe2+-Mg cation-partitioning between olivine and basaltic liquid on pressure, temperature and composition. Contrib. Mineral. Petrol. 101, 261– 273 (1989).
Gladczenko, T. P. et al. South Atlantic volcanic margins. J. Geol. Soc. Lond. 154, 465–470 ( 1997).
Miller, R. McG. in Evolution of the Damara Orogen of South West Africa/Namibia (ed. Miller, R. McG.) 431–515 (Spec. Publ. 11, Geological Society of South Africa, 1983).
Garcia, M. O., Hulsebosch, T. P. & Rhodes, J. M. in Mauna Loa Revealed: Structure, Composition, History and Hazards (eds Rhodes, J. M. & Lockwood, J. P.) 219– 239 (Geophys. Monogr. 92, American Geophysical Union, Washington DC, 1995).
Monierth, C., Johnston, A. D. & Cashman, K. V. in Mauna Loa Revealed: Structure, Composition, History and Hazards (eds Rhodes, J. M. & Lockwood, J. P.) 207– 217 (Geophys. Monogr. 92, American Geophysical Union, Washington DC, 1995).
Arndt, N., Chauvel, C., Czamanske, G. & Fedorenko, V. Two mantle sources, two plumbing systems; tholeiitic and alkaline magmatism of the Maymecha River basin, Siberian flood volcanic province. Contrib. Mineral. Petrol. 133, 297– 313 (1998).
Takahashi, E., Shimazaki, T., Tsuzaki, Y. & Yoshida, H. Melting study of a peridotite KLB-1 to 6.5 GPa and the origin of basaltic magmas. Philos. Trans. R. Soc. Lond. A 342, 105–120 (1993).
Herzberg, C. & Zhang, J. Melting experiments on anhydrous peridotite KLB-1: compositions of magmas in the upper mantle and transition zone. J. Geophys. Res. 101, 8271–8295 (1996).
Arndt, N. T., Kerr, A. C. & Tarney, J. Dynamic melting in plume heads: the formation of Gorgona komatiites and basalts. Earth Planet. Sci. Lett. 146 , 289–301 (1997).
Hards, V. L., Kempton, P. D. & Thompson, R. N. The heterogeneous Iceland plume: new insights from the alkaline basalts of Snaefell volcanic centre. J. Geol. Soc. Lond. 152, 1003–1009 ( 1995).
Hauri, E. H. Major-element variability in the Hawaiian mantle plume. Nature 382, 415–419 ( 1996).
Gibson, S. A., Thompson, R. N. & Dickin, A. P. Ferropicrites: geochemical evidence for Fe-rich streaks in upwelling mantle plumes. Earth Planet. Sci. Lett. 174, 355–374 (2000).
Byers, C., Garcia, M. & Muenow, D. Volatiles in pillow rim glasses from Loihi and Kilauea volcanoes, Hawaii. Geochim. Cosmochim. Acta 49, 1887–1896 (1985).
Sack, R. O. & Ghiorso, M. S. Chromian spinels as petrogenetic indicators: thermodynamic and petrological applications. Am. Mineral. 76, 827–847 ( 1991).
Falloon, T. J., Green, D. H., Danyushevsky, L. V. & Faul, U. H. Peridotite melting at 1.0 and 1.5 GPa: an experimental evaluation of techniques using diamond aggregates and mineral mixes for determination of near-solidus melts. J. Petrol. 40, 1343– 1375 (1999).
Acknowledgements
We thank N. Arndt, M. Bickle, R. Hardy, D. Jerram, G. Milne, S. Milner, A.-K. Nguno, S. Reed, P. M. Smith and M. Tucker for assistance and discussions, and M. Garcia, R. Gill, G. Pearson and P. M. Smith for comments that substantially improved the manuscript. Durham and Cambridge universities funded the research in part.
Author information
Authors and Affiliations
Corresponding author
Supplementary Information
Rights and permissions
About this article
Cite this article
Thompson, R., Gibson, S. Transient high temperatures in mantle plume heads inferred from magnesian olivines in Phanerozoic picrites. Nature 407, 502–506 (2000). https://doi.org/10.1038/35035058
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/35035058
This article is cited by
-
Magmatic processes within the plumbing system of the ultraslow-spreading southwest Indian ridge: constraints from olivine, plagioclase and melt inclusions
Contributions to Mineralogy and Petrology (2024)
-
Petrogenesis of Miocene to Quaternary primitive basaltic magmas in the area of Lake Van (East Anatolia, Turkey): a case for relamination of mantle lithosphere after lithospheric delamination
Contributions to Mineralogy and Petrology (2023)
-
Geochronological and geochemical characteristics of continental basalts of the eastern North China Craton: insights into crust–mantle interaction induced by continental subduction
Contributions to Mineralogy and Petrology (2022)
-
Alkaline rocks from the Deccan Large Igneous Province: Time–space distribution, petrology, geochemistry and economic aspects
Journal of Earth System Science (2022)
-
The life cycle of large igneous provinces
Nature Reviews Earth & Environment (2021)
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.