It could just be shrink/swell of groundwater and clay formations, they may have shrunk during the extended drought and are now getting wet again.
http://news.nationalgeographic.com/...uakes-cause-injection-wells-fracking-science/ In Texas, "it's premature to speculate on the causes of the earthquakes," says Brian Stump, a seismologist and professor at Southern Methodist University, in Dallas, who is studying the recent temblors.
Meh my guess is fat chicks fleeing Oklahoma. I don't want anyone to be alarmed, but it is time to EVACUATE KATY!
There are 2 wells within 10 miles of the epicenter. HOWEVER, 1 of them was built, but then never used (never used fracking) The 2nd well did use fracking..but earthquakes began in the area several months before the well started fracking.