Unexpected Congo volcano eruption explained – New Scientist

An unexpectedly devastating eruption of Nyiragongo in the Congo last year raised questions about exactly what we know about volcanoes. Researchers have now discovered how this sudden event could have occurred.

The eruption of the Nyiragongo volcano on May 22, 2021 killed thousands People are on the run It raised many questions about what exactly preceded this volcanic eruption. Earthquakes and additional emissions of sulfur dioxide, among other things, usually indicate an impending eruption days or weeks in advance. But despite constant monitoring at the site, none of it had been noticed before this devastating explosion.

In a post in temper nature Scientists describe exactly how this could happen. The eruption was an exception to the rule: The 1977 and 2002 eruptions of this volcano were preceded by major earthquakes, a few weeks before they occurred, the researcher and co-author wrote. Delphine Smitarello European Center for Geodynamics and Seismology in Luxembourg.

Read also
Unidentified flying objects don’t make more than they are

reverse order

In the 2021 eruption, lava flows spurted out from the side of the cone, destroying much of the nearby city of Goma. And as if the volcano’s six-hour eruption wasn’t dramatic enough, the residents also experienced more earthquakes in the days that followed. Researchers call this “reverse sequencing.” Where he usually predicted earthquakes, he followed them later.

The first activity was to move magma from the lava lake below the volcano toward the side. The volcanologist says this caused few measurable signals Elske de Zeeuw-Van Dalfsen KNMI and TU Delft, are not involved in this research. “And obviously it was easier than usual for the magma to rise instantly not far from the volcano.”

According to the researchers, this was due to a fracture in the cone-shaped rock of which the volcano is formed. Usually, magma moves underground for a large distance parallel to the surface before erupting at these volcanoes. This displacement causes fractures in the crustal rocks resulting in earthquakes. The subsequent eruption always occurs far from the center of the volcano, tens of kilometers away. Thanks to earthquakes, you can expect such an explosion ahead of time.

In this case, the rupture quickly released magma across the volcano’s flank. Only then did most of the underground movement of magma occur and the accompanying earthquakes began. As a result, the classic vows did not come until then.

Other dangers

De Zeeuw-Van Dalfsen is not surprised by the magma that was previously released due to a fracture of the cone. Given the pressures of the volcano, this in itself is not very strange. This volcano is located in an area where vents constantly appear on the surface of the Earth, called the rift zone.

For scientists, magma flows are cause for concern. Smitarillo: “It then turned out that the unusual activity began only forty minutes ago, which means that the magma was stored at a very shallow depth.” This may pose other risks to the people of Goma and the surrounding area, such as an eruption of a volcano in the city center or in a nearby lake. It’s less than 500m deep, right under their feet.

anticipate and prevent

Now that what an unpredictable volcano can do in a populated environment, it’s become a hub for local authorities and science, he says. Marian Holnessprofessor of petroleum sciences at the University of Cambridge and head of a department at the European Federation of Geosciences, who was not involved in the study.

Holness is very pleased with the way these researchers have worked. “Using fantastic satellite data and state-of-the-art analytical techniques, these people have created something that we should take very seriously.” She believes the study will inspire more research. What this will essentially do is make scientists ask themselves: Are we right? We’ve been around for a very short time compared to the volcanoes, which makes it hard to say if this can happen so often.