Category Archives: Outlets

Mantle Recycles Far Faster Than Thought

The magma that rises from the mantle, forming new islands, may blast more than it bubbles. Where those plumes of magma originate — at the core-mantle boundary or the mantle-crust boundary — and how fast they rise to the surface are still open questions among volcanologists. But now a new study of minerals from the volcano Mauna Loa on the Big Island of Hawaii suggests that some elements made a 2,900-kilometer-long journey from the core-mantle boundary to Earth’s surface in as little as half a million years — quadruple the speed found by previous studies. Continue reading Mantle Recycles Far Faster Than Thought

Rumbles in the Alps reveal rockslides

The ricochet of a rock fall resonates in the mind of anyone who has heard it. But it also sets off subterranean waves detectable by far-off seismic stations — and now researchers are using those signals to remotely model rockslides.

Franziska Dammeier, an engineering geologist at the Swiss Federal Institute of Technology in Zurich, and her colleagues linked five metrics of seismic waves to five physical characteristics of rockslides: volume, runout distance (how far the rocks travel), drop height, potential energy and the angle of reach. The researchers reported their model last week in the Journal of Geophysical Research. Continue reading Rumbles in the Alps reveal rockslides