"But the Wilzetta was a dead fault that nobody ever worried about," says Katie Keranen, an assistant professor of geophysics at the University of Oklahoma.
We're driving in her
red SUV, just south of the Reneaus'
property, when she
stops to point out where the quake tore open a footwide fissure across State Highway 62.
The United States Geological Survey
(USGS) maintains a database of seismically risky areas.
Its assessment of the Wilzetta Fault, Keranen
notes, was "zero probability of expected ground motion.
This fault is like an extinct volcano.
It should never have been active."
When the Wilzetta mysteriously and violently awakened, Keranen
wanted to know why.
partnered with scientists from the USGS
and Columbia University's Lamont-Doherty Earth Observatory.
The morning after the initial foreshock, Keranen's
team scrambled to install three seismometers around Prague.
They did so in time to capture the quake system in unprecedented detail.
says, "We got this beautiful image of the fault plane.
Within a week, her
team and other scientists had placed a total of 25 devices around the fault zone.
One is buried in the Reneaus' backyard.
Now, having completed a yearlong study (just published in the journal Geology), Keranen's research indicates the Oklahoma earthquakes were likely attributable to underground injection of wastewater derived from "dewatering," separating crude oil from the soupy brine reaped through a drilling technique that allows previously inaccessible oil to be pumped up.
"Pretty much everybody who looks at our data accepts that these events were likely caused by injection," Keranen