Simanaitis Says
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DID THE EARTH MOVE FOR YOU, JUST A LITTLE?
THE INTERESTING FACTS WEBSITE reports that “The Earth Shakes Every 26 Seconds, and Scientists Aren’t Sure Why.” Well, this is tantalizing enough to require a perusal and perhaps some additional Internet sleuthing.
A Mere Microseism. Interesting Facts says that back in the Sixties, “Jack Oliver, a researcher at the Lamont-Doherty Geological Observatory, first documented the ‘microseism’ and sussed out that it was emanating from somewhere ‘in the southern or equatorial Atlantic Ocean.’ Not until 2005 was it determined that the pulse’s true origin was in the Gulf of Guinea, just off Africa’s western coast, but to this day scientists still don’t know something just as important: why it’s happening in the first place.”
Wikipedia notes that a microseism, as you might guess, is defined as “a faint earth tremor caused by natural phenomena…. The term is most commonly used to refer to the dominant background seismic and electromagnetic noise signals on Earth, which are caused by water waves in the oceans and lakes.”
Volcanic Activity? Another hypothesis suggests that some microseisms are caused by volcanos. The Interesting Fact website notes, “There does happen to be a volcano on the island of Sǎo Tomé in the Gulf of Guinea near the pulse’s origin point, not to mention another microseism linked to the volcano Mount Aso in Japan, which has made that particular explanation more popular in recent years.”
Interesting Facts observes, “Though there’s no way of knowing when (or even if) we’ll learn the why of this phenomenon, one thing’s for sure: better a microseism than a macroseism.”
Living here in California along the Ring of Fire, I agree.
My Sigh of Relief: “California Isn’t the Most Earthquake-Prone State,” the Interesting Facts website notes: “That would be Alaska, which isn’t just the most earthquake-prone state in the country—it’s one of the most seismically active areas in the world, with 11 percent of all earthquakes occurring there…. The second-largest earthquake ever recorded (a staggering 9.2 on the Richter Scale) took place in the Prince William Sound region there on March 27, 1964, lasting about 4.5 minutes and causing a tsunami that was felt as far away as California.”
New Madrid Again?? And then there’s the New Madrid Earthquakes of 1811-1812. It’s estimated that the initial quake on December 16, 1811, had a magnitude of 7.2–8.2, followed by a 7.4 aftershock that same day. Two additional quakes of similar magnitude occurred in January and February 1812 in this southeast corner of Missouri.
What’s more, on September 14, 2022, “USGS Records Earthquake in Missouri Bootheel.” Television station KAIT8 reports, “The U.S. Geological Survey registered the quake at 3:27 a.m. Wednesday, Sept. 14. According to the USGS, the magnitude 2.1 quake was centered six kilometers (3.7 miles) east-northeast of Steele. It had a depth of 7.3 kilometers (4.5 miles). So far, no one has reported feeling the earthquake.”
“In the last 30 days,” KAIT8 says, “the USGS had recorded 39 earthquakes in the area. Many were clustered along the New Madrid seismic zone.”
Thankfully, they were nothing like 1811–1812: The New Madrid website notes, “The area of strong shaking associated with these shocks is two to three times larger than that of the 1964 Alaska earthquake and 10 times larger than that of the 1906 San Francisco earthquake.”
And, I’m confident, they were a great deal greater than the Gulf of Guinea’s microjudder every 26 seconds, which got us into all this in the first place. ds
© Dennis Simanaitis, SimanaitisSays.com, 2022
Simanaitis Says 
Alaska has more bigger quakes, but it’s also a very big state with active volcanoes, subduction, etc. So it’s certainly the most earthquake-prone state in terms of things that are (actually or potentially) felt.
“Most earthquake-prone” in raw numbers, though, probably still belongs to California, because it’s more densely-covered by seismometers and other recording devices than other US states. Even your phone can join the network with the Shakealert app. But most of those earthquakes are never felt. Look at the USGS earthquakes web site, and play with the settings; at M4.5 and up, Alaska dominates, period. At 2.5 and up, California’s pretty close. At “all magnitudes” California’s way over the top.
Interesting about those microseisms, though. Need to look up the ones near West Africa…
As I get older, time seems to be going faster. now i find out the Earth is spinning faster.Guess I was right.John
I have read that the New Madrid earthquake was so violent that a section of the Mississippi River actually flowed backwards for a short time.