Harmonic tremor usually occurs during an eruption. Hasn’t happened yet. Check out the depth trend for the last 10 days. To my mind this is magma working to the surface, probabaly along an existing fault:
Date Average Depth (KM)
4/18/2011 3.87
4/17/2011 4.24
4/16/2011 4.86
4/15/2011 6.44
4/14/2011 10.17
4/13/2011 11.96
4/12/2011 12.57
4/11/2011 10.26
I am almost sure it is illegal aliens tunneling under the state so they don’t get deported ...
The preceed it, denoting the magmatic movement upward into a magma chamber.
While your avg depth estimates are interesting, they are still in the very shallow category, considering that they are in the interior and any magma would be coming from deeper. The zone is not along any known or identified fault.
Again, volcanology has progressed significantly as well as recognizing seismic signatures of volcanic activity. So far there is nothing to indicate magmatic movement, only normal faulting based upon regional extension.