Posted on October 4, 2015 by Bob Berwyn
New research offers clues on Permian mass extinction. Photo courtesy NASA Blue Marble.
Deep earthquakes could also rattle magma chambers and lead to more eruptions
A long-running debate about the relative importance of an asteroid impact versus the effects of large-scale vulcanism on an ancient mass extinction event may be moot.
A new study by University of California Berkely geologists suggests that both are related. An asteroid impact on Earth may have accelerated volcanic eruptions some 66 million years ago, and together, the planet-wide catastrophes caused the extinction of many land and marine animals, including the dinosaurs.
The study includes the most accurate dates yet for the volcanic eruptions before and after the impact. The new dates show that the Deccan Traps lava flows, which at the time were erupting at a slower pace, doubled in output within 50,000 years of the asteroid or comet impact that is thought to have initiated the last mass extinction on Earth. Continue reading
Filed under: climate and weather | Tagged: climate change, Permian mass extinction, vulcanism | Leave a comment »
Posted on December 20, 2012 by Bob Berwyn
Mt. St. Helens erupts in 1980. Photo courtesy USGS.
New research suggests melting ice sheets could trigger more vulcanism
By Summit Voice
SUMMIT COUNTY — Melting ice sheets may trigger an increase in global volcanic activity, according to researchers with the GEOMAR Helmholtz Centre for Ocean Research (based in Kiel, Germany), and Harvard, who matched historic geological records of vulcanism with warm climate periods.
“In times of global warming, glaciers on the continents are melting relatively quickly. At the same time the sea level rises. The weight on the continents decreases, while the weight on the oceanic tectonic plates increases. Thus, the stress changes within in the earth to open more routes for ascending magma,” said GEOMAR’s Dr Mario Jegen. Continue reading
Filed under: climate and weather, global warming, world news | Tagged: climate, Earth Sciences, Geology, global warming, vulcanism | 1 Comment »