Video showing thermal imagery from the 2022 Mauna Loa eruption which began around 11:30pm HST, November 27, 2022.

Mauna Loa Eruption: Q&A with SDSU Geologist | Information Center

Did the world’s largest energetic volcano present warning indicators earlier than it began erupting? Vic Camp sheds gentle on the science surrounding Hawaii’s Mauna Loa.

Mauna Loa, the world’s largest energetic volcano, started erupting on Sunday, Nov. 27, for the primary time since 1984. The NewsCenter’s Susanne Clara Bard spoke with the geologist from the State College of San Diego Vic Camp to study extra concerning the science behind Hawai’i’s awakening big.

Why is Mauna Loa thought-about the most important energetic volcano on earth?

The Large Island of Hawai’i is made up of 5 giant fused defend volcanoes. The tallest of those is definitely Mauna Kea, which rises 13,803 toes above sea degree. However probably the most huge is Mauna Loa, at 13,679 toes. Understand that your entire volcanic island begins on the seabed, 19,700 toes under sea degree, which provides tremendously to the general quantity. Quantity ensuing from Mauna Loa, estimated at about 18,000 mi3makes it the most important volcano on Earth.

Is it uncommon for Mauna Loa to go so lengthy with out erupting?

Traditionally, Mauna Loa is a really energetic volcano. Nevertheless, it stopped erupting in 1984 after the Kilauea The volcano erupted in 1983. Kilauea continued to erupt for 35 years – till 2018. Now that Kilauea has calmed down, Mauna Loa has grow to be energetic once more. That is fairly typical, as the 2 volcanoes do not often erupt on the similar time. It’s because they share the identical volcanic plumbing system deep beneath the Large Island.

How previous is Mauna Loa in comparison with its neighbours?

Floor lava that erupted from Mauna Loa is geologically very younger, with the oldest being solely about 600,000 years previous. The age of the underwater eruptions underneath the volcano is older, most likely about 1,000,000 years.

All Hawaiian volcanoes are believed to be fed by a mantle plume, which is a conduit of scorching rock with a suspected supply on the core-mantle boundary, about 1,678 miles under the Earth’s floor. Because it rises underneath the Pacific plate, it begins to provide basalt melts that feed the volcanoes of the Large Island. Because the Pacific Plate strikes northwest, the underlying plume (or hotspot) stays basically stationary. Over the subsequent million years, the island will go away the hotspot and a brand new Hawaiian island will seem above it. The method has continued over the previous 70 million years to provide a linear chain of dormant and extinct volcanic islands and seamounts that step by step age northwestward, reaching so far as the Aleutian Trench .

What are the various kinds of volcanic eruptions?

Volcanic eruptions can differ extensively in explosiveness, from probably the most explosive Plinian-type stratovolcano eruptions—exemplified by the 1980 eruption of Mount St. Helens in Washington State—to the least explosive Hawaiian-type eruptions of volcanoes shields, illustrated by Mauna Loa. Explosive eruptions clear magma into tremendous ash, sending small pyroclastic fragments and volcanic gases tens of kilometers into the ambiance, whereas devastating the encircling landmass with lethal pyroclastic flows and volcanic mudflows. As a substitute, Hawaiian eruptions produce solely very small eruption columns above the volcano, often a kilometer or much less in peak. Whereas silica-rich Plinian-type eruptions are too explosive to provide lava flows, milder Hawaiian-type eruptions can produce huge volumes of fluid lava that may circulation nice distances from volcanic vents.

Did the Mauna Loa eruption have any warning indicators?

Volcanic eruptions should not solely predictable, however extra predictable than earthquakes. In truth, rising magma (liquid rock under the floor) is commonly first acknowledged by seismic exercise of a selected kind (harmonic tremors) which signifies transferring magma. Because the magma rises, it additionally decompresses, permitting gases dissolved within the magma to flee to the floor via small vents referred to as fumaroles. If there’s a sharp enhance in fumarole exercise, it may additionally signify a possible eruption. One other indication is that groundwater temperatures could rise on account of rising magma, resulting in elevated steam eruptions and geyser exercise. The bottom itself could start to bulge upward, indicating a really shallow rise of magma close to or under the volcano.

What are the potential dangers related to the eruption?

You would possibly suppose that the non-explosive nature of Hawaiian eruptions makes them much less dangerous, however sadly, there are risks to fret about. There have been makes an attempt to divert the transferring basalt lava, however these haven’t been very efficient, so constructions constructed within the path of the transferring basalt are often destroyed, burned to the bottom, or buried in hardened basalt. Most basalt lava flows can simply be handed, however are troublesome to cease.

Supply vents can produce eruption columns that rise a couple of hundred meters above the floor. These will likely be composed of globular plenty of scorching liquid basalt, a lot of which can harden within the air into pyroclasts (fragments of basalt bombs, rocks and ash) earlier than hitting the bottom. In excessive wind circumstances, these fragments could be stretched into tremendous filaments referred to as Pelé’s hair (named after the Hawaiian goddess of volcanoes). Falling fragments could be harmful close to air vents. However the largest concern is atmospheric contamination from the manufacturing of so-called vog (aka volcanic smog), which is made up of sulfur dioxide and different volcanic gases that blend and react to type poisonous compounds. Vog could be very acidic, so respiratory it in may cause respiratory issues for these residing close to the eruption.

Extra info on the Mauna Loa eruption is accessible at USGS.

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