bloop

Bloop was an ultra-low-frequency, high amplitude underwater sound detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) in 1997. By 2012, earlier speculation that the sound originated from a marine animal was replaced by NOAA's description of the sound as being consistent with noises generated via non-tectonic cryoseisms originating from glacial movements such as ice calving, or through seabed gouging by ice.

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