Debate Stirs On Hotspot VolcanoesThe most common theory in recent years has been that hotspots exist in the Earth where molten lava wells up from deep below, creating volcanoes such as those that formed Hawaii and Iceland and seismic zones such as Yellowstone. But Gillian Foulger of the University of Durham, England, and James Natland of the University of Miami point out in the journal Science that efforts to find evidence of hotspots using seismic waves have not produced results... In a separate paper in the same journal, Donald J. DePaolo and Michael Manga of the University of California, Berkeley, agree that so far seismological studies searching for hotspots have not produced the expected proof. But they say they expect the evidence to be found. Theoretical and laboratory studies predict deep hot plumes, they note, and there is supporting evidence in the Hawaiian Island chain, with the rising lava building a line of islands as the overriding crust moves along, evidence of a stationary hotspot deep in the earth.
by Randolph E. Schmid
Wandering hot spots worry geologists"Hot spots" where plumes of molten magma break through the Earth's crust appear to be wandering across the planet - a discovery that undermines many of the accepted ideas about how the Earth's tectonic plates are moving... [A] new study by Robert Duncan of Oregon State University in Corvallis and his colleagues shows that the Hawaiian hot spot has probably shifted... "People suspected that hot spots were moving," says geologist Robert Butler of the University of Arizona in Tuscon. "But the one they all wanted to hang onto was the biggest, baddest hot spot of them all - the Hawaiian hot spot."
by Betsy Mason
December 18 2001