'Sounds of the ocean' include the rumble of submarine volcanoes

Dec. 4 (UPI) -- Most volcanic eruptions happen underwater -- at the bottom of the ocean. Most volcanic research focuses on above-ground eruptions.

To correct for the imbalance, some researchers are calling for improved monitoring efforts. One of those researchers is Gabrielle Tepp of the Alaska Volcano Observatory and the U.S. Geological Survey.

Tepp is in New Orleans this week to discuss the potential of remote-montiroing efforts with attendees of the 174th Meeting of the Acoustical Society of America.

"It's very difficult to study underwater volcanoes because it's hard to put instruments in the water, especially long-term," Tepp said in a news release.

During the presentation, Tepp will detail the recordings of two underwater eruptions. Both involve seamounts rising from the floor of the Pacific Ocean. The first, Ahyi, is part of the volcanic chain that formed the Northern Mariana Islands, while the second, Bogoslof, is part of the magmatic system that yielded the Aleutian Islands.

Despite their similarities, the duo produced distinct soundscapes.

Ahyi's eruption in 2014 was characterized by a series of gunshot-like explosions, each pop separated by a few minutes. Bogoslof's eruption produced prolonged rumbles, some lasting several hours.

The signatures of both eruptions could be picked up in faraway seismometers, but researchers aren't sure if the expansion of seismometer networks would be cost-effective for the study of submarine volcanoes.

"Eruptions that create a loud enough sound, in the right location, can travel pretty far, even from one ocean to another," Tepp said. "It makes you wonder, how many of these signals have we seen on distant instruments where nobody knew what they were, and it's a submarine volcano from halfway around the world?"

Improved monitoring of submarine volcanoes could help scientists better predict hazards and warn travelers. Underwater eruptions can produce rafts of rubble that can clog harbors or block shipping lanes. If the volcano is shallow enough, gas and ash can reach the surface and enter the atmosphere, potentially affecting air travel.