On Apr 8, 6:47*am, dave wrote:
http://earthquake.usgs.gov/earthquak...1379106/us/ind...

Thanks, Dave - let's see, where was I at 3:40 PM - I think I was here
at home in San Lorenzo near Hayward, east bayshore. Did not feel it,
although I see someone in Contra Costa County noticed it. We don't
get much shaking from most quakes - even a 5.0 within 15-20 miles only
gives us a tiny notice. Not sure why - must be the specific
location. People all around us will say, "Feel that???" and we say
"Feel what?"

Parkfield is the place where the USGS has a seismograph network set up
because quakes of a specific size - around MM 6.0 or so IIRC - have
happened there with considerable regularity. However, the last
predicted "clockwork" quake there was supposed to happen several years
ago (it did not yet occur), and nothing bigger than yesterday's 4.0
has been recorded there since (that I know of). So, maybe this one
has the seismologists buzzing...a foreshock of something bigger to
come?

A MM 6 in Parkfield would get folks excited. A MM 7.0 there would
give Gilroy/Hollister/Monterey/San Jose some trouble, and maybe SF
too. And of course, an 8 there would get LOTS of attention.

Bruce