Monday, May 4, 2015

An Earthquake in Michigan

Even though the focus of this blog is the New Madrid seismic zone sometimes events come to notice that would be of interest to the reader.  Occasionally earthquakes occur in the Central and Eastern United States that are not in seismic zone. One of these occurred in Michigan over the weekend. It was a magnitude 4.2 and was centered in southern Michigan.  Of note is the several state area in which the earthquake was experienced.  This was a phenomena noted with the New Madrid earthquakes which were felt for vast distances across the continent. For more information visit Michigan earthquake

Historically Michigan is not noted for earthquake activity. They occasionally occur there but are not common,   During the New Madrid earthquakes Detroit and the surrounding area was noted to have felt them.

Another weekend, another earthquake

It seems the New Madrid seismic zone has been active on a weekend basis in recent times.  While last weekend was mild and sunny inviting people outside to enjoy the spring an earthquake occurred near Ridgley, Tennessee. It occurred in the early evening of May 1st. For more information look at Ridgley earthquake.

Thursday, April 2, 2015

The April 1st Steele Missouri Earthquake(Magnitude 4.0)

April 1st passed quietly at CERI until late in the evening when the New Madrid seismic zone decided announce its presence once again. At 10:51 in the evening an magnitude 4.0 earthquake occurred near Steele, Missouri. It was felt regionally and in the Memphis area.  This is just another reminder that the New Madrid seismic zone remains active and produces earthquakes that can be felt above the ones that we record just instrumentally.  For further information look at the event page Steele Missouri Earthquake

Friday, March 6, 2015

Another Weekend Earthquake( and a boom)

In the midst of the snow and ice of last weekend.(Not the current snow and ice) The New Madrid seismic zone had a 3.1 magnitude earthquake.  From friends I have in the area they reported  it as  a "shake" and also noted  a booming sound. For more information about this earthquake please consult the CERI website at Recent Earthquake
As a historic note the New Madrid earthquake were noted for making noise too. This account details what one eyewitness  experienced at Lexington, Kentucky:
"About half after two o'clock yesterday morning, a severe shock of an Earthquake was felt at this place: the earth vibrated two or three times in a second, which continued for several minutes, and so great was the shaking that the windows were agitated equal to what they would have been by a hard gust of wind. We are informed by those who were awake by the commencement, that a sound like distant thunder was heard to the westward, previous to the agitation of the earth."
"About half after two o'clock..."Lexington Kentucky Gazette,12/17/1811,Pg 3, Col 3. New Madrid Far Field Number, 73.

Friday, February 6, 2015

The earthquake of February 7th

Two hundred and three years ago the last of the New Madrid earthquakes occurred.  It was considered by many the strongest of the earthquakes and producede some dramatic effects. Here is an eyewitness account of the earthquake near the epicenter in the New Madrid, Missouri area. Read and enjoy:

In descending the Mississippi on the night of the 6th February, we tied our boat to a willow bar on the west bank of the river, opposite the head of the 9th Island, (counting from the mouth of the Ohio) we were lashed to another boat--About 3 o'clock on the morning of the 7th, we were waked by the violent agitation of the boat, attended with a noise more tremendous and terrific than I can describe or any one conceive, who was not present or near to such a scene--The constant discharge of a heavy cannon might give some idea of the noise for loudness, but this was infinitely more terrible, on account of its appearing to be subterraneous.
As soon as we waked we discovered that the bar to which we were tied was sinking, we cut loose and rowed our boats for the middle of the river--After getting out so far as to be out of danger from the trees, which were falling in from the banks--the swells in the river were so great as to threaten the sinking of the boat every moment. We stopped the oarholes with blankets to keep out the water. After remaining in this situation for some time, we perceived light on the shore which we had left--(we having a lighted candle in a lantern on our boat,) were hailed and advised to land, which we attempted to do but could not effect it, finding the banks and trees still falling in.
At day light we perceived the head of the tenth Island. During all this time we had made only about four miles down the river--from which circumstance, and from that of an immense quantity of water rushing into the river from the woods--it is evident that the earth at this place or below, had been raised so high as to stop the progress of the river, and cause it to overflow its banks--We took the right hand channel of the river at this Island, and having reached within about half a mile of the lower end of the town, we were affrightened by the appearance of a dreadful rapid or falls in the river just below us; we were so far in the suck that it was impossible now to land--all hope of surviving was now lost and certain destruction appeared to await us! We having passed the rapids without injury, keeping our bow foremost, both boats being still lashed together.
As we passed the point on the left hand below the Island, the bank and trees were rapidly falling in. From the state of alarm I was in at this time, I cannot pretend to be correct as to the length or height of the falls--but my impression is that they were about equal to the rapids of the Ohio. As we passed the lower point of the Island looking up at the left channel, we thought the falls extended higher up the river on that side than on the right.
The water of the river after it was fairly light, appeared to be almost black, with something like the dust of stone-coal--We landed at New Madrid about breakfast time, without having experienced any injury--The appearance of the town and the situation of the inhabitants, were such as to afford but little relief to our minds. The former elevation of the bank on which the town stood, was estimated by the inhabitants at about 25 feet above common water--when we reached it the elevation was only about 12 or 13 feet--There was scarcely a house left entire--some wholly prostrated, others unroofed and not a chimney standing--The people all having deserted their inhabitations, were in camps and tents back of the town, and their little water crafts, such as skiffs, boats and canoes hauled out of the water to their camps, that they might be ready in case the country should sink.

Account of Matthias Speed from New Madrid Far Field Database  Number 56 from
the  Frankfort(KY) American, March 20, 1812.


Monday, January 26, 2015

A Weekend Earthquake

It seems that the New Madrid seismic zone likes to be active when the workaday world is at rest during the weekend. On Saturday an earthquake occurred southwest of Blytheville Arkansas.  The magnitude was 2.9 and should have been felt by people near the epicenter. For more details go to Arkansas earthquake  If you felt it go to the links provided to report what you experienced. Any data is appreciated.

Friday, January 23, 2015

The Second Great Quake

On this day 205 years ago the second of the New Madrid earthquakes occurred.  Near the epicenter eyewitness accounts were confused and scattered probably due to the numerous aftershocks of the December 16, 1811 earthquake. But at a distance away from the epicentral area eyewitnesses noted it as a distinct event. Here is an account from Coshockton Ohio:
"This morning, at seventeen minutes past eight o'clock, a severe shake of a earthquake was felt in this place. It lasted nearly a minute; it shook so as to nearly half empty a bucket, standing on the floor, full of water; and the river being frozen over, it caused the ice to crack considerably. A stone chimney in the house of col. Williams in this place, seven by five feet square, solid and well built, was so severely shaken as to cause it to crack in several places; and one or perhaps more brick chimneys in this place have been considerably injured by the shock. I have been informed that several houses in the neighborhood of this place were so shook that much of the chinkin dropt out; and the commotions of the trees and bushes was so great as to cause persons I the woods to observe the phenomenon. The shock was succeeded by a thick haze, and several people were affected with giddiness, although the air was quite serene at the time of the shock. The course of the above shock was from S.W. to N.E. nearly.
A. JOHNSTON."
Boston Independent Chronicle February 17, 1812, Page 1, Column 1, New Madrid Compendium Far Field item Number 37
The A. Johnston is no relation to our Arch Johnston, but Arch appreciated the reference from the past that shared his name.