MooPig Report from the Middle: Mag 7 Madrid finally Resting?

(March 25) — A crack in the earth that resulted in the biggest quakes known in the center of the United States — and which have raised fears of a "big one" sometime this century — might actually be in the process of shutting down, scientists now suggest.
Evidence in the rocks suggest major earthquakes at the New Madrid system occurred not just in 1811 and 1812, but also in 1450 and 900, roughly 500 years apart.
Midwest Fault May Be Shutting Down
LiveScience \ By Charles Q. Choi, LiveScience

This earthquake zone threatens parts of Illinois, Indiana, Missouri, Tennessee, Arkansas, Mississippi and Kentucky. It has been rumbling again in recent years, leading researchers to ask whether another devastating quake could hit in upcoming decades. A magnitude 5.2 earthquake on a northeastern extension of the system in southern Indiana was felt from Kansas to Georgia in 2008.

To see how active the New Madrid system is, scientists recently used nine GPS antennas mounted on the ground over the heart of the fault in southern Missouri and Tennessee to investigate the earthquake zone over the course of eight years.

The new research on this earthquake zone, dubbed the New Madrid fault system, could change what we know of how quakes in the middle of continents work.

Three of the largest earthquakes in North America recorded in history occurred at the New Madrid system over the course of two months from 1811 to 1812. These magnitude 7 events shook the earth with enough power to force the Mississippi River to temporarily flow backward.

This earthquake zone threatens parts of Illinois, Indiana, Missouri, Tennessee, Arkansas, Mississippi and Kentucky. It has been rumbling again in recent years, leading researchers to ask whether another devastating quake could hit in upcoming decades. A magnitude 5.2 earthquake on a northeastern extension of the system in southern Indiana was felt from Kansas to Georgia in 2008.

To see how active the New Madrid system is, scientists recently used nine GPS antennas mounted on the ground over the heart of the fault in southern Missouri and Tennessee to investigate the earthquake zone over the course of eight years.