Does Earth have a pulse? In the early 1960’s seismologist Jack Oliver discovered a seismic pulse happening every 26 seconds. At that point in time, its location was unknown but thought to be close to the equatorial Atlantic Ocean. Then in 1980, a U.S. geologist, Gary Holcomb, looked at the pulse with new digital seismometers but did not discover the source. Finally, in 2005, a graduate student at the University of Colorado, Greg Bensen, found the same signal. Benson and his advisor, Mike Ritzwoller, triangulated the pulse to the Gulf of Guinea which is off the coast of western Africa. This small blip is detected by seismic monitors on many continents. Yet still, the discovery of how and why this “pulse” occurs is unknown. Ah, the seismic enigma’s of the Earth! A friend in Mt. Vernon, Indiana, Jeanie Topper, gave me a printout many years ago of an article from a newspaper, The Sunday Look. It was written by J. Robert Smith and entitled, “The Day Terror Shook the Tri-State”. Jeanie had hand written the date of publication, 12/16/1996, on the article. The newspaper article is an informative account of the 1811 and 1812 earthquakes originating from the New Madrid tectonic plate fault. There were three shocks with the intensity of 10 on the Rossi-Forrel scale: December 16, 1811, January 23, 1812 and February 7, 1812. During that time frame and into March of 1812, 1,874 severe aftershocks were felt. Minor aftershocks went on for two more years. “At Big Prairie, Illinois, (southeast of where Carmi now stands) a resident,Yearby Land, said the water in his father’s well was not still for two years.” It was also in Big Prairie that a hole in the ground cracked open so deep the bottom could not be seen.
The pioneers living at Boone’s Fort in New Haven felt the shaking. “Samuel Dagley, Robert Grant, Paddy Robinson and the Rev. R.M. Davis wondered if the Plankeshaw Indians were on the warpath.”
J. Robert Smith writes, “Clouds of rising dust caused periods of darkness. Sulpher gas hissed out of crevices, the angry sky turned red and purple. Waves of visible depressions rolled across the earth. When they broke open they left parallel fissures 600 to 700 feet long, one a mile in length. In some cases persons trapped in these fissures were rescued with difficulty.” One can imagine the groaning and rumblings of an earth being torn apart. The sharp roar like a “discharging canon” made our ancestors believe that the end of the world was near. The noise of forest trees swaying violently sounded like thunder with branches swinging so rapidly that they created sharp cracking sounds like a whip even though there was little or no wind. People prayed and repented. “They remembered the great comet that had swept the summer and autumn skies, the battle of Tippecanoe a month earlier.” Not only were there the horrific sounds created by the quake itself, but pigs squealed, dogs howled and cowered, and cows in pastures came bellowing back towards the barns—a discordant symphony. The New Madrid earthquake is the greatest recorded quake in U.S. history, surpassing both the Charleston, S.C. quake of August 31, 1886 (the second worst) and the California earthquake of April 18, 1906. So, do we have to be concerned that the New Madrid fault line will bring about another series of devastating earthquakes? My attention was drawn to the recent Evansville Courier & Press article, April 21, 2021, “Ready for the Big One?” The three full page article relates that the New Madrid Seismic Zone has shown little activity in the last 100 years whereas the Wabash Valley Seismic zone has been kicking up its heels. “In the last 20 years there have been three magnitude 5 or better earthquakes on the Wabash Valley Fault.” Since I live a few hundred feet from the Wabash, that caught my attention! Checking maps of the Wabash Valley Fault, which show bright yellow stars for the epicenter, we are sitting right on top of it. The damage received depends on the kind of soil upon which your home/business sets. If you are brave enough to research it, you can learn more about the liquefaction and acceleration potential of an earthquake. There are certain types of sediment which are more susceptible to liquefaction—exactly the kind upon which the little riverside village of New Harmony sits. There is more to this story, how during the New Madrid Earthquake, the Captain of a riverboat from Yellow Bank, which is now Owensboro, Kentucky, could not find anywhere to tie up because the riverbanks kept breaking off in big chunks from the shoreline. How he had to maneuver to avoid huge trees floating in the raging waters. How the pilot of the boat did not recognize where they were because the river banks had changed, even an island had disappeared. It has been 200 years since the “Big One” from the New Madrid Fault. Somewhere I read that typically the tectonic plates react to pressure every 500 years or so. I wonder how many hundreds of years it has been since the Wabash Valley Tectonic Fault had major trembling and shakes? Psalm 77:18 “The voice of thy thunder was in heaven: the lightnings lightened the world: the Earth trembled and shook.” [email protected] ©Ann Rains May, 2021
*The block prints shown are from the Sunday Look newspaper article.
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