FORT WORTH, Texas (AP) - Could a rash of small earthquakes in areas with a lot of oil and gas drilling be a side effect of the North Texas energy exploration boom?
The Fort Worth Star Telegram reports that quakes in the town of Azle have thrust injection wells into the spotlight.
The state has about 35,000 active injection wells. But 7,000 of those are now being used for disposal.
The widespread use of hydraulic fracturing to extract natural gas and oil from shale formations has increased disposal well use. They send wastewater deep underground.
And there's some evidence disposal wells can make the earth quiver.
The powerful Texas Railroad Commission plans to hire a seismologist to study this and other issues. But outside researchers are already attempting to answer the question.
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