Tuesday, September 01, 2009
PBS Nova "Science Now" airs danger of Midwestern earthquakes (New Madrid Fault)
Today, Sept. 1, PBS NOVA “Science Now” had a fifteen minute short “Earthquakes in the Midwest”, with link here. Try the “find the fault” application!
The report briefly described the three earthquakes near New Madrid, MO around 1811, before any large cities were built. There seems to exist a subduction “dimple” that never became a full-fledged plate boundary under the Mississippi River area. The show presented downtown Memphis and St. Louis, both of which could have tremendous damage if there were to occur a large quake in the area. The Memphis area has about 200 silent quakes a year.
The scientists went caving, in very muddy conditions, to look at evidence of past earthquakes, which seem to occur every 500 years or so. We may be safe for a while.
Attribution link for Wikimedia picture of Memphis monorail.