September 7, 2011
Iceland Keeps Eye On Katla Volcano After Tremors
Iceland´s Katla volcano has been the site of small but increasing earthquake activity but scientists said Tuesday there is no immediate concern that the increased seismic activity will trigger a dangerous eruption. Earthquakes around Katla are common, increases in cluster earthquakes are not, reports the Associated Press (AP).“It´s one of the most feared volcanos, so we´re closely monitoring it,” Pall Einarsson of the University of Iceland told AP's Gudjon Helgason. “That said, it´s normal for earthquakes to be detected around Katla. What´s a bit unusual is that we´re seeing swarms of small earthquakes, some occurring every 10 minutes or so.”
Iceland is in the center of a volcanic hot spot in the Atlantic´s mid-oceanic ridge. Eruptions have been commonplace throughout Iceland´s history, often triggered by seismic activity when the Earth´s plates move and magma pushes its way to the surface from under the crust of the planet.
Like earthquakes, predicting the timing of volcanic eruptions is an imprecise science. Last year´s eruption of the Eyjafjallajokull volcano forced evacuations and halted international air travel for weeks because of a continuing ash cloud that drifted over Europe.
History has shown that when Eyjafjallajokull volcano erupts, Katla isn´t far behind with its own show and threatens disastrous flooding if its ice cap melts. Katla typically awakens every 80 years or so and is due for activity as it last erupted in 1918. Katla had two small eruptions in 1955 and 1999, neither of which managed to break the ice covering its 6 mile-wide caldera.
July of this year has shown signs of increased activity around Katla and has since grown even stronger. The strongest earthquake detected so far has been a 3.0 magnitude which caused flooding to wipe out a bridge, Bloomberg reports.
“Like people, each volcano has a different personality of sorts,” Einarsson told AP. “We look at the behavior, try to analyze patterns and then try to come up with an explanation. This is a bit difficult to interpret so far, but it´s correct to say that it signals some sort of activity in the volcano and some sort of magna intrusions are probably taking place.”
“Everyone has their eyes on a big Katla eruption,” said Andy Russell with Newcastle University´s Earth Surface Processes Research Group, who travels frequently to Iceland for research. “You can never say never, but I don´t think there´s need for alarm right now.”
Iceland is one of the few places in the world where a mid-ocean ridge actually rises above sea level. Many volcanic eruptions along the ocean basin often go undetected because they can´t be easily seen.
Image Caption: Dormant Katla in Iceland. Credit: Getty Images