The evacuation order for all residents of Miyake Island was lifted Thursday evening after authorities indicated that volcanic activity on the island is subsiding.
The danger of an eruption that affects the ground or sea surface has “almost disappeared,” authorities said, prompting Mayor Tadayuki Hirose of the village of Miyake to initially lift an evacuation order for some 1,100 residents of the eastern part of the island — 66 hours after the order was first issued.
In the evening, Hirose also lifted the evacuation order for some 700 residents of the western parts of the island.
The mayor’s decision came after an announcement by volcanologists earlier Wednesday that ruled out the possibility of a volcanic eruption on the eastern part of the small island or from Mount Oyama in its center.
On Thursday evening, the Coordinating Committee for the Prediction of Volcanic Eruptions, an advisory panel to the Meteorological Agency, also said the evacuation order for the entire island could now be lifted.
About 1,800 residents have been sheltering in local schools and a welfare facility for the elderly on the 55.5-sq-km island since the threat of a volcanic eruption first arose earlier in the week.
The prediction committee told a news conference that the focus of quakes on the seabed off the west coast of the island still required close monitoring.
It also said changes in crust movements have subsided and the center of magma activities has moved to the sea off the island’s west coast. Experts added that the pressure of magma under the ocean floor has weakened.
The committee also confirmed the same day that the change in sea color observed on Tuesday off the island’s west coast was caused by a “fairly active” eruption below the ocean floor.
Meanwhile, a series of strong earthquakes measuring between 4 and 5 on the Richter scale jolted Niijima and Kozu island in the Izu chain on Thursday, the Meteorological Agency said.
The strongest of the earthquakes hit Kozu Island at around 12:11 p.m., registering lower 5 on the Japanese seismic scale of 7 — or 5.1 on the Richter scale — 4 on Niijima and 3 on Miyake Island.
The agency said the quakes were not directly caused by volcanic activity on Miyake Island, but said it is possible the volcanic activity stimulated the crust under the sea and set off the quakes.
The agency said Thursday morning that there has been no dramatic change in volcanic activity in the sea area, or in crustal movement, which is being monitored by a global positioning system.