In the news Chaiten explodes

摘要

Authorities in southern Chile have ordered the complete evacuation of two towns after the Chaiten volcano (Fig. 1) spewed lava and blasted ash more than 20 km into the sky {Daily Telegraph, 7 May 2008). Rains carpeted surrounding areas in ash and mud, prompting the provincial governor to order the evacuation of the town of Chaiten. More than 4000 people had fled the first eruptions, which were the volcano's first in 450 years, but fresh blasts on 6 May sent a thick column of ash even higher into the stratosphere with the expectation that thick trail of lava would slowly coat the surrounding area. Rodrigo Rojas of the National Emergency Office said the situation had deteriorated suddenly, with the volcano erupting with pyroclastic material on a much greater scale. Luis Lara, a government geologist, said he did not expect a catastrophic collapse of the volcano, but was concerned that the eruptive column could do so, causing material to be displaced down its sides and into nearby areas.