amNewYork spoke with Rowena Lohman, professor of seismology at Cornell, to get the science behind Tuesday's earthquake.
How does an earthquake in Virginia reach as far as Canada?
The earth's crust in this region is much older and kind of cold, and because of that, earthquakes out here ring like a bell, we say: really brightly and for a long time, compared to a dampened-type in other regions. ... If you had the same size earthquake in California you wouldn't feel it nearly as far away, and you'd feel it much less.
Is New York at a risk of aftershocks?
Most of the time, the largest aftershock is about 1.5 units smaller than the main shock. ... So you probably wouldn't feel it unless you were in a really big, shaky building.
How often to earthquakes of this size hit the region?
The last one to hit Virginia of that size was about 100 years ago, and in that area they happen about once a century. ... On the whole they're very infrequent. ... There hasn't been a really big one in New York City in a very long time, though there have been some smaller ones in New Jersey. Since these big ones occur so rarely, they're very hard to study.
Follow Tim Herrera on Twitter at @tim_herrera