Drilling might be culprit behind Texas earthquakes

http://news.yahoo.com/s/ap/20090612/ap_on_re_us/us_texas_earthquakes_drilling;_ylt=At0tUBbq6EctDGlWUza5dvGs0NUE;_ylu=X3oDMTFpNmxzaGNuBHBvcwM1OARzZWMDYWNjb3JkaW9uX21vc3RfcG9wdWxhcgRzbGsDZHJpbGxpbmdtaWdo

By JEFF CARLTON, Associated Press Writer Jeff Carlton, Associated Press Writer – Fri Jun 12, 6:22 pm ET

CLEBURNE, Texas – The earth moved here on June 2. It was the first recorded earthquake in this Texas town's 140-year history — but not the last. There have been four small earthquakes since, none with a magnitude greater than 2.8. The most recent ones came Tuesday night, just as the City Council was meeting in an emergency session to discuss what to do about the ground moving.

The council's solution was to hire a geology consultant to try to answer the question on everyone's mind: Is natural gas drilling — which began in earnest here in 2001 and has brought great prosperity to Cleburne and other towns across North Texas — causing the quakes?

"I think John Q. Public thinks there is a correlation with drilling," Mayor Ted Reynolds said. "We haven't had a quake in recorded history, and all the sudden you drill and there are earthquakes."

At issue is a drilling practice called "fracking," in which water is injected into the ground at high pressure to fracture the layers of shale and release natural gas trapped in the rock.

There is no consensus among scientists about whether the practice is contributing to the quakes. But such seismic activity was once rare in Texas and seems to be increasing lately, lending support to the theory that drilling is having a destabilizing effect.
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