Icelandic water making waves in seismology
REYKJAVIK, Iceland -- A tin bath on the cliffs of northern Iceland, where locals take a dip to treat skin complaints, could help scientists give a lifesaving early warning of big earthquakes.
People from the town of Husavik have long used the piping hot water, pumped up from 4,920 feet below the earth's surface, to treat diseases like psoriasis.
Scientists hope that measuring the changes in its chemical balance will provide a countdown to a quake, something thought impossible until now.
The theory is that pressure changes and movements along geological faults, such as the Mid-Atlantic Ridge which cuts through Iceland, cause the chemical signature of water deep in the earth's crust to change. Just such changes were evident when a magnitude 5.8 earthquake struck the Tjornes Fracture Zone near Husavik, Iceland's whale-watching capital, in September 2002.
"There was a huge peak in the concentration of some chemicals in the water -- some went up 1,000 percent before the earthquake," said Lillemor Claesson from Stockholm University and the Nordic Volcanological Center in Reykjavik.
Scientists have never been able to warn people of earthquakes with any accuracy. They can give a broad picture -- that a quake is likely over the next decades -- or they can give warnings a few minutes ahead of one. Mass evacuations have been impossible.
Claesson is cautious about claiming too much significance for the research, published in Geology, the journal of the Geological Society of America.
But if the kind of changes seen in the water in Iceland -- one of the most geologically active countries in the world -- prove widespread and occur at set intervals they could help scientists make more accurate predictions of when a seismic event will happen.
"Ten weeks before the earthquake we had a really big peak in chromium, and iron. Then five weeks before manganese increases enormously. Two weeks before there was a peak in zinc and one week before there is a copper peak," Claesson said.
Not every scientist is as optimistic.
Although changes in groundwater have been observed before and after earthquakes, they don't "give you very useful information about magnitude, location, and time," said David Booth, senior seismologist at the British Geological Survey, who said he had not read Claesson's research.
"It will be hundreds of years" before accurate earthquake prediction is possible. 