Why Didn’t the Earth Shake on November 11, 2018?
The mysterious seismic waves that rang the planet like a bell
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On November 11, 2018, a ripple ran through the entire planet. Low-intensity seismic waves were detected from Africa to Hawaii.
It all began at around 9:30 AM Universal Time, 15 miles off the coast of Mayotte, an island located between Africa and Madagascar.
The waves then traveled north. They set off sensors in Zambia, Kenya, and Ethiopia.
Soon, they buzzed on the other side of the oceans: Chile, New Zealand, Canada, and Hawaii: 11,000 miles away from Mayotte.
The sensors rang for 20 minutes.
But what is disturbing scientists is not what happened — it’s what did not happen.
The waves
Low-intensity seismic waves like the kind detected on November 11 normally occur at the tail end of a very strong earthquake.
But there was no earthquake. No human appears to have felt them.
A seismologist at Columbia University who specializes in unusual earthquakes told National Geographic, “I don’t think I’ve seen anything like it.”
Everything about these waves was strange. They spread around the globe, they had a monotone ring, and the signal was a clean zigzag.
Nothing about them was typical for waves sent out by earthquakes.
So what did send them?
Theories
The mysterious waves conjured many images in people’s imagination.
Some speculated that the reason was a meteor strike. A celestial object, undetected, hit Earth and caused a tremor.
Others suggested an eruption of an underwater volcano.
And some: a sea monster.
We don’t know the answer for sure but scientists have been able to tip the scales towards one of these theories.
The French Geological Survey (BRGM) proposed that a new center for volcanic activity might be forming off the coast of Mayotte.
The region has been still for the past 4,000 years but it’s not completely cold. The island itself is the byproduct of volcanic activity.
BRGM’s theory is that the low-intensity waves were a symptom of magmatic movement under thousands of feet of water.
Their analysis was supported by other geologists.
GPS data shows that the Mayotte island had moved more than 2.4 inches to the east and 1.2 inches to the south. This seems consistent with a magma body “squishing its way through the subsurface near Mayotte.”
So while we don’t know the definitive answer, scientists lean towards one explanation. The volcanic roots of Mayotte are slowly starting to wake up after a 4,000 years of sleep.
