What lies below?

Mon, 14 Dec 2015 09:17:19 -0500

Scientists using a new tomographic model of Earth's mantle have identified 5,000-kilometer-wide swells of potentially hot material in the lower mantle that the researchers say confirm the existence of plumes. Credit: French and Romanowicz, Nature, 2015.

Technological advances continue to improve the resolution of our view of Earth’s interior, but disagreement remains over what we’re viewing. In a recent Nature paper titled, “Broad plumes rooted at the base of the Earth’s mantle beneath major hot spots,” Scott French, a computational scientist at the Department of Energy’s National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory, and Barbara Romanowicz, a seismologist at the University of California at Berkeley, reported the development of the most detailed model yet of the structure of the mantle.

The question of mantle plumes

Mon, 14 Dec 2015 08:49:28 -0500

Over the years, many different locations have been proposed as hot spots. Some of the most well-known proposed sites are labeled with red dots in this diagram, which also depicts the borders of Earth's tectonic plates. Credit: K. Cantner, AGI.

In 1963, J. Tuzo Wilson first proposed that volcanic chains like the Hawaiian Islands form when a tectonic plate drifts over a “hot spot” in the mantle. Eight years later, Princeton geophysicist W. Jason Morgan suggested that such hot spots — he initially proposed about 20 around the world — were fueled by narrow plumes of hot mantle rock rising from the core-mantle boundary.

Mantle Plumes on EARTH Magazine

What lies below?

The question of mantle plumes