There's been a surge in earthquakes in the U.S. over the last few years. In Texas, there are 10 times the number of earthquakes now than just a few years ago.
Scientists say it's likely linked to the boom in oil and gas activity, meaning that people who never felt the ground shake are starting to.
Here's how Pat Jones of Snyder, Texas, describes the earthquake that struck her town in 2010: "It just sounded like some car hit the back of our house. We got up and checked around and we didn't see anything or hear anything else."