"Vibrations" have been observed at many seismic stations and official CERI / Midwest USGS data centers throughout the region. This can only be described as low final vibration over a very large area.
They cannot be confused with earthquakes elsewhere around the planet, something that has not previously been observed in such a large area.
Maybe there are some malfunctions in the sensor network? Could it be that something is causing this "interference"? Or is what the observation stations are detecting are detected low-frequency oscillations occurring in reality?
Could this be a sign that Yellowstone is about to erupt? Or maybe the New Madrid Fault will suddenly wake up?
Time will tell what it is …
Here are the main links…. click on CERI, SLU, or any other "nodes" … then select 2012-30-11 (most current charts) … and then compare several days or weeks or months in the past by going back through the links (listed by date):
Online Internet Seismic Server also shows this activity:
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