Current Postgraduate Students
Publication details for Prof Gillian FoulgerFoulger, G.R. (2002). Plumes, or plate tectonic processes? Astronomy & Geophysics 43(6): 6.19-6.23.
- Publication type: Journal Article
- ISSN/ISBN: 1366-8781, 1468-4004
- DOI: 10.1046/j.1468-4004.2002.43619.x
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
Hotspots – large volcanic provinces – such as Iceland, Hawaii and Yellowstone, are almost universally assumed to come from plumes of hot mantle rising from deep within the Earth. At Iceland, perhaps the best-studied hotspot on Earth, this hypothesis is inconsistent with many first-order observations, such as the lack of high temperatures, a volcanic track or a seismic anomaly in the lower mantle. The great melt production there is explained better by enhanced fertility in the mantle where the mid-Atlantic spreading ridge crosses the Caledonian suture zone. The thick crust built by the excessive melt production encourages complex, unstable, leaky microplate tectonics, which provides positive feedback by enhancing volcanism further. Such a model explains Iceland as a natural consequence of relatively shallow processes related to plate tectonics, and accounts for all the first- and second-order geophysical, geological and geochemical observations at Iceland without special pleading or invoking coincidences.