Earth Quake?

Yesterday morning something woke the cat and me, about 3:30. I felt a rumble and shake, and thought the heating unit was messing up. The cat wanted out, so I let him, and when I went back to bed I heard the furnace running.

When I got up, I asked my husband if he had noticed anything, but he had slept through it. I didn't think much more about it, until I saw a news brief that a 2.5 magnitude quake had been recorded in Virginia on Monday morning.

Not really related to gardening, but an interesting phenomena.

http://earthquake.usgs.gov/earthquakes/recenteqsus/Quakes/se032811a.php#details