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Chance of Usu blast recedes

DATE, (Japan): Chances of an explosive eruption from a rumbling volcano in northern Japan appear to have diminished for now, experts said on Monday.

Authorities, however, remained on the alert as Mount Usu on the north Japanese island of Hokkaido spewed smoke and ash into the sky for the 11th consecutive day and some 13,000 evacuees still cannot go home for good.

"The eruptions appear to have stabilised for the near future," said Hiromu Okada, a Hokkaido University professor.

The statement marked a change from the dire warnings issued since late last week, when scientists believed the volcano was heading for a deadly explosive eruption accompanied by flows of hot ash, gas and rock.

Small-scale eruptions like the ones that have taken place since the 732-metre (2,402 ft) peak began erupting on March 31 for the first time in 22 years are helping to relieve pressure below the earth, reducing the chances of an explosive eruption, scientists said.

"There have been no significant new developments that we can see since last Friday," said Koji Takada at the Volcanology division of the Meteorological Agency.

"As long as the volcano continues as it is now, with small eruptions of steam and ash, it will dissipate energy below the earth's surface and keep down the chances of a large eruption."

But he said the situation still requires careful monitoring and could change at any time.

"A real danger signal would be if the volcano suddenly falls silent, because then pressure would build up underground and could lead to a major eruption," he added.

Until Monday, scientists had feared the mountain was preparing to blow its top, citing seismic activity that suggested magma was moving in ways that could lead to an explosive eruption. The volcano had also formed new craters and fissures on a nearly daily basis.

But Takada said that as of Monday morning, scientists had detected no fresh craters or fissures. Reflecting the diminished danger, nearly 400 evacuees were allowed to return home for seven hours to check on their homes and pick up necessary belongings, and authorities said more would be allowed home over the next few days if volcanic activity remained stable.

Taking steps to prepare for the possibility that a large number of evacuees may not be able to return home over the long term, the government said on Sunday that 1,500 temporary housing units had been sent to the area.-Reuters