Hawaii: 34 earthquakes rattle world’s largest active volcano raising fears of eruption

USGS reminds people to prepare emergency plan as seismic activity increases

Mauna Loa, the world’s largest active volcano, covering half of the Big Island of Hawaii, was ratted by 34 small earthquakes on Sunday.

Though only registering small magnitudes, scientists have warned citizens that the mounting seismic activity could signal that an eruption may be possible in the near future.

There have been 155 earthquakes greater than 1.5 on the Richter scale in the past seven days, and 740 in the past month, including a 4.3 on 3 April.

Sunday’s largest tremor was a 3.2 magnitude quake that struck Pahala, south of the summit of Mauna Loa at 8.08pm local time. A 3.0 tremor also struck in the afternoon.

In March, the US Geological Survey said that as the volcano continues to awaken from its slumber, it would be a good time for people to revisit their personal emergency plans in the event of an eruption.

Historical data accompanying a press release from USGS shows that in previous eruptions it could take just hours for lava flows to reach populated areas.

“Now is the time to revisit personal eruption plans. Similar to preparing for hurricane season, having an eruption plan in advance helps during an emergency,” the agency wrote.

A “go-bag” with essential items and important documents is recommended, should evacuations be ordered in the event of an eruption.

Rising to 13,681 feet above sea level (4,169m), Mauna Loa, or “Long Mountain” in Hawaiian, also extends three miles to the ocean floor, making it taller than Mount Everest from its base.

The Big Island also has three other active volcanoes — Mauna Kea, Kilauea, and Hualalai. Kilauea has been erupting since November.

Mauna Loa has erupted 33 times since official records began in 1843. The last eruption was more than 35 years ago when the volcano spewed lava from 25 March to 15 April, 1984.

Eruptions of the volcano tend to produce large, fast-moving lava flows that can impact communities on both the east and west sides of the Big Island from Kona to Hilo.

A lava flow map of Mauna Loa on Hawaii’s Big Island prepared by the US Geological Survey (USGS)

Hilo in the east of Hawaii has been threatened by seven lava flows since the 1850s. In 1984, the lava stopped approximately four miles outside of the city.

On the south and west sides of the island, lava flows have reached the coast eight times, including three times in 1950.

A USGS ranking of the biggest volcanic threats in the US has Kilauea in the top position, followed by Mount St Helens and Mount Rainier in Washington State.

Mauna Loa is 16th on the list, which is determined by 24 factors relating to the threat to the nearby population and the threat to aviation.