It would be interesting...
...to plot well spikes at an angle perpendicular to the propagating wave, document the shadow zone and the refracted convergent zones. Or a simple map. Sounds like a good science fair project.
For me, alas, no time, just curiosity.
I was in the middle of dinner on the 25th with the inlaws when the P-waves would have hit the ground under my feet. I think, I haven't figured it down to the minute, or anything. That, and the occassion called for an alcoholoic beverage or four, couldn't be sure what I felt...
jms