People in Dallas were surprised by a swarm of small earthquakes that started shaking the city a couple of days ago. There have been 11 by last count. And the quakes, though new to the Dallas area, are just the most recent in a major upsurge in earthquakes in Texas over the last few years.
Earthquakes were pretty much unheard of in the Dallas area until 2008. Since then there have been a lot of these swarms of quakes. In Irving, Texas, where this new cluster is located, there have been more than 50 in the last several years, according to the city manager. This current swarm started around September.