09-27-2024, 04:55 PM
I just thought I would pop this article in since it seems to present a similar (above sea level) seismic signature...
From ArsTechnica: Bizarre, nine-day seismic signal caused by epic landslide in Greenland
Earthquake scientists detected an unusual signal on monitoring stations used to detect seismic activity during September 2023. We saw it on sensors everywhere, from the Arctic to Antarctica.
We were baffled—the signal was unlike any previously recorded. Instead of the frequency-rich rumble typical of earthquakes, this was a monotonous hum, containing only a single vibration frequency. Even more puzzling was that the signal kept going for nine days.
Initially classified as a “USO”—an unidentified seismic object—the source of the signal was eventually traced back to a massive landslide in Greenland’s remote Dickson Fjord. A staggering volume of rock and ice, enough to fill 10,000 Olympic-sized swimming pools, plunged into the fjord, triggering a 200-meter-high mega-tsunami and a phenomenon known as a seiche: a wave in the icy fjord that continued to slosh back and forth, some 10,000 times over nine days.
To put the tsunami in context, that 200-meter wave was double the height of the tower that houses Big Ben in London and many times higher than anything recorded after massive undersea earthquakes in Indonesia in 2004 (the Boxing Day tsunami) or Japan in 2011 (the tsunami which hit Fukushima nuclear plant). It was perhaps the tallest wave anywhere on Earth since 1980.
I know this doesn't exactly line up with the thread topic... but it occurred to me that seismic data doesn't always relate to earthquakes... and maybe sometimes those negative values might fall into other categories of events, like this one.
From ArsTechnica: Bizarre, nine-day seismic signal caused by epic landslide in Greenland
Earthquake scientists detected an unusual signal on monitoring stations used to detect seismic activity during September 2023. We saw it on sensors everywhere, from the Arctic to Antarctica.
We were baffled—the signal was unlike any previously recorded. Instead of the frequency-rich rumble typical of earthquakes, this was a monotonous hum, containing only a single vibration frequency. Even more puzzling was that the signal kept going for nine days.
Initially classified as a “USO”—an unidentified seismic object—the source of the signal was eventually traced back to a massive landslide in Greenland’s remote Dickson Fjord. A staggering volume of rock and ice, enough to fill 10,000 Olympic-sized swimming pools, plunged into the fjord, triggering a 200-meter-high mega-tsunami and a phenomenon known as a seiche: a wave in the icy fjord that continued to slosh back and forth, some 10,000 times over nine days.
To put the tsunami in context, that 200-meter wave was double the height of the tower that houses Big Ben in London and many times higher than anything recorded after massive undersea earthquakes in Indonesia in 2004 (the Boxing Day tsunami) or Japan in 2011 (the tsunami which hit Fukushima nuclear plant). It was perhaps the tallest wave anywhere on Earth since 1980.
I know this doesn't exactly line up with the thread topic... but it occurred to me that seismic data doesn't always relate to earthquakes... and maybe sometimes those negative values might fall into other categories of events, like this one.
