APRIL 7: Japan's erupting Mount Usu is threatening to blow with a violent explosion and a speeding tide of oven-hot volcanic debris, experts said today."Crustal movements are concentrated under the foot of the western part of Mount Usu," said Noritake Nishide, an official for the volcanic division at the meteorological agency."Magma has risen in these areas and there is a strong possibility of seeing a lava dome there," said the official."Before a lava dome is formed it is very likely we are going to see an explosive eruption followed by a pyroclastic flow," Nishide said.A pyroclastic flow is a wall of 100-200 celsius volcanic debris that can engulf towns, moving at the speed of a bullet train with a height exceeding a two-storey house.Craters located at the foot of Mount Usu, on the northern island of Hokkaido, were just one km away from residential areas in the worst-affected town of Abuta.
