Hot and Deep: Melting during late-stage rifting in Afar

A recent paper in Nature,
Dr Derek Keir, from Geology and Geophysics research group at Ocean and Earth Science, has recently been involved in a study on the Afar Rift Valley. The Nature paper by Ferguson and coauthors used geochemical data from lavas erupted along the the Afar rift valley to constrain the origin of magmatism in the region. They conclude that melting is generated at great depths – 80 kilometres or more – and is driven by an unusually hot region of the mantle. The authors then matched their observed melting depth to that predicted from geodynamic models. Both observations and model showed that thinning of the tectonic plate over the past 30 million years has been much less than previously assumed in Afar, and suggests that an abrupt phase of plate thinning during the final stages of break-up would be required for an ocean basin to form.

For a general summary of the paper please see the news and views article at: