New Madrid Fault Hit Directly by M2.8 Earthquake

New Madrid Fault Hit Directly by M2.8 Earthquake
5 Comments

The US Geological Survey reported last week their research showing extremely large, damaging and deadly earthquakes start with a series of very small quakes.  With that in mind, it is unsettling to many the New Madrid Fault in Missouri has just had a Magnitude 2.8 earthquake; directly on the fault line!

The New Madrid seismic zone of southeast Missouri and adjacent States is the most seismically active in North America east of the Rockies.

During the winter of 1811-1812 three very large earthquakes devastated the area and were felt throughout most of the Nation. They occurred a few weeks apart on December 16, January 23, and February 7. Hundreds of aftershocks, some severely damaging by themselves, continued for years.

Prehistoric earthquakes similar in size to those of 1811-1812 occurred in the middle 1400's and around 900 A.D. Strong, damaging earthquakes struck the southwestern end of the seismic zone near Marked Tree, Arkansas in 1843 (magnitude 6.3), and the northeastern end near Charleston, Missouri in 1895 (magnitude 6.6).

Since 1900, moderately damaging earthquakes have struck the seismic zone every few decades. About twice a year people feel still smaller earthquakes that do not cause damage.

Earthquakes in the central and eastern U.S. are typically felt over a much broader region than in the western U.S. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast. A magnitude 4.0 eastern U.S. earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).

Faults

Earthquakes everywhere occur on faults within bedrock, usually miles deep. The earthquakes of the New Madrid seismic zone occur within a large network of faults called the Reelfoot rift. The rift formed about 500 million years ago, when this region was stretched in the northwest-southeast direction.

Along a northeast-southwest zone at least 70 km (40 mi) wide and 500 km (300 mi) long, the rocks in the rift were slowly dropped down about 1-2 km (1 mi) along some of the faults. Now the region is undergoing east- west shortening, and the ancient faults of the Reelfoot rift are being reactivated to generate earthquakes. Today the Reelfoot rift and the New Madrid seismic zone are 2,000 km (1,200 mi) from the nearest plate boundary, which is in the Caribbean Sea.

The network of faults in the seismic zone is buried beneath hundreds to thousands of feet of sand and mud. Four of the largest faults are recognized as alignments of abundant small earthquakes, and movements along two of these faults dammed rivers and created lakes during the earthquakes of 1811-1812.

A few more deeply buried faults were detected during oil and gas exploration, and a few small faults are known from geologic mapping. However, many earthquakes occur away from the few known faults, so there must be additional, unknown faults that can generate earthquakes in the seismic zone.

Accordingly, the best overall guide to seismic hazard in the New Madrid seismic zone is the earthquakes themselves.

Today's quake is shown on the more localized map below along with date, time and depth: Shallow . . .

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  • This commment is unpublished.
    ReadyGo · 3 months ago
    Earthquakes ...... the best resource on this is dutchsinse.com or dutchsinse on youtube........ takes a good hour for his report but he goes into the hows and whys....... he is the only source I know of that can ALMOST predict what is to come ......and why.
  • This commment is unpublished.
    transformationtime · 3 months ago
    Astonishingly few commantaries on that (important) subject dear subcribers - but may be you already know of the great danger and damages that could derive from reappearing strong earth quakes along that particular fault line - to happen even before an often discussed west coast catastrophe. Hal certainly has his very good reasons to report about this incident. I have read some very alarming prophecies and commentaries about a szenario that could happen there in a not too distant future from now. And I wished what I read was fake news. People usually like to play or speculate with the knowledge they are quite aware of, sometimes for reasons of laziness or hopes things will be managable as always. In this case I would express my serious doubts and stay on alert on that issue.
  • This commment is unpublished.
    Mark Mundy · 3 months ago
    I read this article immediately after reading another article from Drudge this morning https://heraldpublicist.com/scientists-finally-know-how-big-earthquakes-start-with-many-smaller-ones173938/.

    There are no such things as coincidences.
  • This commment is unpublished.
    Steven Holsten · 3 months ago
    I live about 30 to 35 west of New Madrid in Kennett, MO. These small quakes happen quite often. I hope it relieves stress on the fault.
  • This commment is unpublished.
    Billy Williams · 3 months ago
    I'm glad you shared this hal, I live near it and it wasnt even on our news