I experienced the same thing around the Portland metro area a few year ago. The ground would vibrate and I used to think that it felt like mini
earthquakes. This happened quite frequently and I used to check and see if there were earthquakes nearby, but the earthquakes were never at the same
time as when I felt the ground rumbling.
However, the Northwest does have lots of earthquakes and not all of them are big enough to record, so you may not see them listed in the newspaper.
Also, later on I figured out that the rumblings I felt were around the same time that Mount St. Helens was acting up. When the volcano was active
from 2004 to early 2008, there were literally hundreds of earthquakes every day.
There is always something shaking up here.
www.pnsn.org...






