The Mauna Loa volcano makes up about half of the landmass of the island of Hawaii (USA). That is, 3,962 meters above sea level and another 12,802 meters below sea level. The crater has erupted 33 times since 1843, making it one of the most active volcanoes on earth.
However, experts believe the worst is yet to come as Mauna Loa has accumulated magma in its volcanic chamber for the past eight years.
A small earthquake could trigger an eruption at Mauna Loa
Using measurements of the magma inflow, a local team of volcanologists has determined Mauna Loa is about to erupt again.
“An earthquake could change the game, releasing gases from the magma akin to shaking a soda bottle, creating enough pressure and buoyancy to rupture the rock and cover the sky.” – Falk Amelung, geologist and volcanologist at the University of Miami
A total of 0.11 km2 of new lava has entered the volcanic chamber since 2014, causing small eruptions in the molten rock, according to a 2021 study by researchers at the Rosenstiel School of Marine and Atmospheric Sciences – University of Miami, published in Scientific Reports. Such unprecedented lava movement severely affects the sub-horizontal fault on which this crater sits.
So the topographical risk on the west side of Hawaii is significant given that it is the largest active volcano in the world. Volcanologists estimate that this pressure in the volcanic chamber could trigger an earthquake of magnitude 6 or higher. This in turn would lead to a large eruption on the island.
Mauna Loa has “prepared for a massive eruption”.
Changes in magma flow usually do not pose much of a hazard, as the volcanic rock always restrains the impact. Unfortunately, in 8 years this lava has changed the shape of the world’s largest volcano and increased the likelihood of an eruption.
In 2021, using GPS devices and satellite data, the team discovered that the soil around the fault had been eroded by magma intrusions. This had never been observed on an active volcano before.
“We can explain how and why the magma body has changed in recent years, but not when we will see the effects. But this will ultimately lead to better models to predict the next eruption site” – Falk Amelung.
Such magmatic intrusions can therefore increase the likelihood of an earthquake and sudden eruption. This would explain why the 1950 and 1984 eruptions were preceded by strong earthquakes, the first of which took only three hours to reach shore.
However, predicting when this phenomenon will occur is an incredibly complex task, and volcanologists have no evidence of it. They’re just saying it’s going to happen soon given how many topographic changes the volcano has gone through.
Should we be concerned about the world’s largest active volcano?
Probably yes if you live in Hawaii. However, it is unlikely that Mauna Loa’s eruption will affect other topographical regions, if recognized in time.
The results of this study will be used to predict future earthquakes and eruptions in the area to increase the safety of local residents. EIt is to be hoped that volcanologists will figure out the date of this dangerous eruption before the world’s largest volcano decides to “start the game”.