Earthquakes, Volcanic Eruptions At Mount Etna – Forces From Earth’s Spin Maybe Responsible

Eddie Gonzales Jr. – MessageToEagle.com – Tremendous forces pulling on Earth’s surface as the planet spins – may trigger earthquakes and eruptions at volcanoes, new research suggests.

An eruption at Mount Etna on October 30, 2002, from the International Space Station. The eruption, triggered by a series of earthquakes, was one of the most vigorous in years. Ashfall was reported in Libya, more than 350 miles away. Credit: NASA

Researchers suggest that polar motion and subsequent shifts in Earth’s crust may increase volcanic activity and seismic activity and bursts of magma near Italy’s Mount Etna increased when Earth’s rotational axis was furthest from its geographic axis.

Earth’s spin doesn’t always line up perfectly with its north and south poles. Instead, the geographic poles often twirl like a top around Earth’s rotational axis when viewed from space. Every 6.4 years, the axes line up and the wobble fades for a short time – until the geographic poles move away from the spin axis and begin to spiral once again.

This phenomenon, called polar motion, is driven by changes in climate due to things like changing seasons, melting ice sheets or movement from tectonic plates. As polar motion fluctuates, forces pulling the planet away from the sun tug at Earth’s crust, much like tides due to the gravitational pull from the sun and moon. The tide from polar motion causes the crust to deform over the span of seasons or years. This distortion is strongest at 45 degrees latitude, where the crust moves by about 1 centimeter (0.4 inches) per year.

“I find it quite exciting to know that while climate drives Earth’s spin, its rotation can also drive volcanoes and seismicity,” Sébastien Lambert, a geophysicist at Paris Observatory in France and lead author of the study, said in a press release.

The new findings, however, don’t allow scientists to forecast volcanic activity.

“It’s the first time we’ve found this relationship in this direction from Earth’s rotation to volcanoes,” Lambert said. “It’s a small excitation process, but if you accumulate a small excitation over a long time it can lead to measurable consequences.”

More – here

Research

Written by Eddie Gonzales Jr. – MessageToEagle.com Staff