Mount Tongariro, a volcano in New Zealand’s North Island, erupted for the first time in 115 years, creating an ash cloud that closed roads and disrupted regional air travel before moving off the coast.
The eruption was reported by a member of the public about 11:50 p.m. local time yesterday, New Zealand Police said in an e-mailed statement. Government scientists are monitoring the event, which they said was driven by steam rather than magma, and can’t rule out further explosions.
“I wouldn’t be surprised if there were more small-scale eruptions,” Brad Scott, a volcanologist at GNS Science, a government agency, told reporters at a televised news conference. Ash fell to a depth of as much as 15 millimeters and was drifting east, he said.
Tongariro is one of three volcanoes in the middle of the North Island, about 340 kilometers (211 miles) north of the capital city Wellington. It lies just to the north of Mount Ngauruhoe, which was used by film director Peter Jackson to depict Mount Doom in his movie trilogy based on J.R.R. Tolkien’s “Lord of the Rings” novels.
There were no reports of damage or injuries, the Ministry of Civil Defense & Emergency Management said in a statement. The ministry lifted a potential threat notice for the area in the early afternoon, based on GNS Science advice that eruption activity had subsided, according to its website.
No evacuations were ordered although some people did briefly leave their homes voluntarily, the ministry said. Residents are being urged to check water supplies for ash contamination.
Hiking tracks and huts around the mountain are closed. Three hikers were safely evacuated from a hut where they had been spending the night, Nic Peet, area manager for the Conservation Department, told reporters.
An ash cloud extending as high as 12 kilometers formed after the eruption, and moved quickly east, the National Institute of Water & Atmospheric Research said in an e-mailed statement, citing satellite imagery. The cloud had blown off the coast by late afternoon, it said.
Air New Zealand Ltd., the nation’s biggest carrier, resumed flights to most regional airports east of Tongariro after canceling services earlier because of the risk from the ash, it said in a statement on its website. Services to Napier on the east coast remained grounded.
State highways in the area reopened after being initially closed because of ash falls, the New Zealand Transport Agency said on its website.
Ski fields on Mount Ruapehu, about 20 kilometers south of Tongariro, are unaffected, according to their websites.
While GNS Science on July 20 raised the alert status at Tongariro due to increased seismic activity, nothing had indicated the volcano would erupt yesterday, Scott said.
“It just snuck up on us,” he said.
Tongariro’s last confirmed eruption was 1897, according to government scientists. Ruapehu erupted in 1995 and 1996, creating an ash cloud and flows of volcanic ash, known as lahars, that disrupted transport.
GNS Science is also monitoring White Island, an offshore volcano about 180 kilometers north of Tongariro, where small, unconnected eruptions occurred Aug. 5 and again yesterday, Scott told reporters.
The explosion yesterday came less than a month before the two-year anniversary of a magnitude 7 earthquake that struck near the South Island city of Christchurch. A subsequent temblor on Feb. 22, 2011, devastated the heart of the city, killing 185 people and wrecking thousands of homes and buildings. There have been 10,560 quakes in the area since Sept. 4, 2010, according to University of Canterbury research.