Since last fall, more than 20 low-level earthquakes have shaken homes and businesses around Azle, a rural community northwest of Fort Worth. The town lies in the heart of the Barnett Shale, and some residents, neighbors and experts blame the oil and gas industry for the underground instability. Some point specifically to injection wells, which pump drilling wastewater deep underground at high pressures.
State oil and gas regulators say it's too early to know if the seismic activity is linked to the injections wells, but experts outside Texas say the connection is real. This map, compiled by WFAA using data from the Texas Railroad Commission, which regulates oil and gas activity in the state, and the U.S. Geologic Survey, shows injection wells and their proximity to the earthquakes. Clicking on the icons shows details about both.
Interactive map by Matt Goodman, WFAA.com.