A seismic recorder on Mayotte first detected the buzzing, though it was not the first one people noticed.
There was a hum that no one could hear. It was a seismic event that occurred on November 1
From there it circled the entire world, though it was unusual (earthquake-ish enough) that almost nobody has noticed, as Maya Wei-Haas reports for National Geographic. However, some people paid attention to it, and this sparked a search for the source of the buzz that she reported still was not resolved.
– ******* Pax (@ matarikipax) November 11, 2018
and here in Wellington, New Zealand … https: //t.co/fNfOZpWQNe pic.twitter.com/VGb1oRu8pc
– **** * ** Pax (@matarikipax) November 11, 2018
The humming was strange for several reasons, according to National Geographic. First, it only rang with a single extremely low frequency, like a well-tuned bell. Seismic waves usually contain many different frequencies. Second, the wave appeared and circled the planet without the usual signs of an earthquake. No one in the area felt a shiver, and the "p-waves" and "s-waves" associated with the buzzing, the kind of waves you actually feel during an earthquake, were so weak that they were almost undetectable. However, a November 12 French government report found that Mayotte had slipped south by 2.4 inches (6 cm) to the east and 1.2 inches (3 cm). [The 10 Biggest Earthquakes in History]
Scientists have proposed a number of possible explanations for the strange seismic event near Mayotte, Wei-Haas reported. But not confirmed yet. Perhaps a "slow earthquake" has hit the area, a type that does not cause much shaking because it occurs over a longer period of time. Perhaps a magma bubble was burrowing beneath the surface or floating in a large hole in the crust in a manner that interacted with the local geology to produce resonant ringing. The researchers even speculated about a meteorite attack, although this seems unlikely. The exact cause remains a mystery for the time being.
For more information about unusual seismic events, see the full report in National Geographic
. Originally published on Live Science.