Thursday Throwdown: Neanderthals, the source of flood basalts and more
Some news! Get it while it is hot!
Neanderthals and volcanoes: A recent study by Naomi Cleghorn and others that appeared in Current Anthropology lays the blame for the extinction of the Neanderthals on the Campanian Ignimbrite (amongst others). By examining ash layers in Russian caves that were frequented by Neanderthals, it appears that ~40,000 years ago a number of volcanic ashes accumulated, right before Neanderthals go extinct. The volcanic ash layer related to the Campanian Ignimbrite appears to lack much plant life (pollen, etc.), suggesting that much plant life in Europe was killed due to the eruption, thus likely leading to a decline in the large mammals that the Neanderthals hunted. The fact that the Neanderthal populations were concentrated in Europe – versus the dispersed human populations in Asia and Africa along with Europe—may have lead to their demise.
Deep source of the Siberian Traps: The flood basalts of Siberia–better known as the “Siberian Traps“—which erupted ~250 million years and may have prompted a major extinction on Earth may also have had a deeper source than previously believed. A study in Earth and Planetary Science Letters suggests that the source of the magmas for the flood basalts was close to the core-mantle boundary – rather than the upper mantle where most magmas that erupt are believed to be sourced. Dr. Smirnov and Dr. Tarduno also think that the source of the Siberian Traps may be the same as the North Atlantic Magmatic Province – another flood basalt that may be related to the opening of the Atlantic Ocean. This suggests that there might be very long-lived mantle features—we’re talking 250 million years or more – that could be the source of these flood basalts. (Just don’t believe headlines like “Magma from the Earth’s Core nearly destroyed all Life!“)
New Global Volcanism Program Weekly Volcanic Activity Report: I think the title there says it all – but look for highlights such as earthquakes at Machin in Colombia, plumes from Dukono in Indonesia and explosions from Suwanose-Jima in Japan.
Volcano news from other blogs: There has been a lot of great volcano-related posts on other blogs as well – check out posts on Eyjafjallajökull and magma-ice interactions on the Volcanism Blog, how to distinguish different eruptions in andesitic volcanic deposits on Magma Cum Laude.