During the early stages of continental breakup, injection of magma into the crust and mantle below Ethiopia has allowed the tectonic plate to extend without marked thinning of the crust, suggests a study published online this week in Nature Geoscience. This prolonged period of extension is now being followed by stretching and thinning of the tectonic plate, causing voluminous lava eruptions at the surface, and subsidence of the land below sea level. Ian Bastow and Derek Keir analysed the timing and spatial distribution of magmatic and tectonic activity observed in Ethiopia ― a region where rifting of the African continent is well exposed. The researchers found that faulting, stretching and magma intrusion are all important, but each at different times during the breakup of the continent.
doi: 10.1038/ngeo1095 | Original article