Upsweep

Upsweep is a sound detected by the U.S. National Oceanic and Atmospheric Administration's (NOAA) equatorial autonomous hydrophone arrays.

The sound's source is roughly located at 54°S 140°W / 54°S 140°W / -54; -140, in a remote region of the Pacific Ocean between New Zealand and approximately 2,500 miles due west of the southern tip of South America.

[4][5][6] The sound consists of a long sequence of repeating vertical "sweeps" from low to high frequency lasting for roughly three seconds each and was loud enough to be heard by the entire Equatorial Pacific Ocean autonomous hydrophone array system.

Submarine volcanic eruptions are characteristic of the formation of rift zones found in all of the Earth's major ocean basins.

[10] The Monterey Bay Aquarium Research Institute described the acoustic characteristics of these phenomena as:[11] Underwater volcanoes make a variety of sounds when they erupt, from short, sharp cracks to booming explosions and low rumbles.