SALT LAKE CITY, May 27 (UPI) -- A powerful earthquake that rocked Alaska in 2002 changed the timing and behavior of some of Yellowstone's geysers and hot springs.
Researchers at the University of Utah said the quake -- which registered 7.9 on the Richter Scale, was one of the strongest to hit North America in 150 years. Though other large quakes have been known to alter the activity of nearby geysers and hot springs, the Denali fault earthquake, on Nov. 3, 2002, is the first known to have changed the behavior of hydrothermal features at such great distances.
The researchers said less than 18 hours after the Denali earthquake in Alaska, the jolt also triggered more than 1,000 small earthquakes in Yellowstone over the course of a week. The quakes ranged in magnitude from minus 0.5 to just under 3.0. Tiny quakes have negative magnitudes because modern seismic equipment can detect quakes smaller than was possible when the logarithmic magnitude scales were devised, researchers said.
