Eerie undersea 'bloop' mystery solved: It isn't Cthulhu

Published November 29, 2012 8:09pm

After 15 long years, scientists have finally found an explanation for the creepy undersea "bloop" noise recorded in the 1990s by the US National Oceanic and Atmospheric Administration (NOAA).

The NOAA, in a notice on its website, said the sounds were likely of ice quakes generated by icebergs cracking and fracturing.

"The broad spectrum sounds recorded in the summer of 1997 are consistent with icequakes generated by large icebergs as they crack and fracture. NOAA hydrophones deployed in the Scotia Sea detected numerous icequakes with spectrograms very similar to 'Bloop,'" it said.

It said the icequakes were used to acoustically track iceberg A53a when it disintegrated near South Georgia Island in early 2008.

NOAA said icequakes can be detected on multiple sensors at a range of over 5,000 km.

"Based on the arrival azimuth, the iceberg(s) generating 'Bloop' most likely were between Bransfield Straits and the Ross Sea, or possibly at Cape Adare, a well-known source of cryogenic signals," it said.