As strange as it seems, the ground can play a big part in how well an earthquake travels.

Firstly, due to the positing of the North American Plate boundary and nearby fault lines, the West Coast sees a lot of activity. Because of all this activity, the crust along the West Coast is and also a lot weaker in comparison to the East Coast, where the plate boundary is further out to sea. Seismic waves find it much easier to travel through colder, stronger, less abused areas of the Crust than more offset surfaces such as in California. As Holly explains:

"The West Coast is worse due to the collision of the Pacific and North American plate, creating the San Andreas fault line. The East Coast's closest plate boundary is Mid-Atlantic ridge, and that's pretty far away from it! [The East Coast's crust is] cooler and stronger, but [it] does not necessarily have a thicker crust though. But the colder surface definitely makes waves travel faster!"

The actual bedrock can have an impact on how earthquakes travel. In Virginia, the Piedmont contributes to the , created millions of years ago, out of very old rock. The mountain ranges were created out of faulted marine sedimentary rocks, volcanic rocks and were part of the original Pangaea supercontinent. The old and faulting rock of the Appalachian range, combined with the coolness of the east coast, and potential activity in the Seismic Zone encourages further-moving waves . The breaks in the bedrock of California usually stop this kind of reflex.

"Virginia is part of the Appalachian Range, so a similar formation to Scotland and Norway [once all of these countries were attached and the range ran throughout]--very old rock squashed in Pangaea supercontinent collision 440 Ma [million years ago]," Holy tells us. "This created loads of faulting, hence the wide spread of seismic propagation."