USGA: Kilauea volcano could erupt explosively

A large explosion in Hawaii's Kilauea volcano could lead to an explosive eruption and send boulders, rocks and ash into the air in the coming weeks, the US Geological Survey (USGA) said on Wednesday.

The volcano, located on the US state's Big Island, is one of the world's most active volcanos. Last Thursday, it began releasing lava into two fissures that opened 25 miles (40 kilometers) from the summit crater.

Read more: Why risk living on a volcano like Kilauea?

The USGA warned that more violent eruptions could begin mid-May, ejecting blocks up to six feet (two meters) in diameter to over a half-a-mile from the crater. It may also shoot pebbles up to several miles, and dust areas up to 20 miles away with ash.

"This is the first of perhaps more events like that to come," said Tina Neal, the scientist-in-charge at the USGS Hawaiian Volcanoes Observatory.

Neal added that the receding lava lake resembles conditions seen before a major eruption in 1924, an explosion that killed one person and sent rocks, ash and dust into the air for 17 days.

Neighborhoods evacuated

The Kilauea volcano has destroyed 36 structures since the fissures opened. Lava flow in the area has paused, but sulfur dioxide gas, which causes acid rain and can be life-threatening, remains a hazard.

Hawaii County Civil defense said all 1,900 residents of the Leilani Estates and Laipuna Garden areas have been evacuated. People are continuing to visit Hawaii Volcanoes National Park, where Kilaueau is located, but the area has some restrictions.

A magnitude 6.9 earthquake, the second largest of the last century in Hawaii, shook the southern flank of the volcano on Friday. There is no indication of when the eruption might stop, or how far the lava might spread.

The volcano has been in a state of nearly constant eruption for 24 years. It predominantly releases lava in effusive eruptions that flow into the ocean, but it occasionally experiences more explosive events. In recent years it has mostly released lava in remote areas inside a national park or along the coastline.

dv/rc (AP, Reuters)