HOUSTON Dec 20 Oklahoma is imposing guidelines
to reduce the risk of earthquakes caused by hydraulic fracturing
in its oil-rich shale formations, the first rules in the state
to target the controversial production technique.
The guidelines are aimed at the South Central Oklahoma Oil
Province (SCOOP) and Sooner Trend Anadarko Basin Canadian and
Kingfisher counties (STACK) formations, which are anticipated to
account for most new oil and gas activity in the state,
authorities said on Tuesday.
The moves by the Oklahoma Corporation Commission's Oil and
Gas conservation Division and the Oklahoma Geological Survey
came as earthquakes in the state have risen sharply since the
shale boom and the use of hydraulic fracturing, or fracking.
The guidelines, which go into effect immediately, require
producers to implement mitigation plans following an earthquake
of magnitude 2.5 or more and to suspend operations following a
quake of magnitude 3.5 or greater.
While the guidelines are technically voluntary, the Oklahoma
legislature this year gave the Oklahoma Corporation Commission
powers to make compliance mandatory.
So far, directives have focused on curbing use of injection
wells for the disposal of saltwater, a normal byproduct of
Oklahoma experienced almost 900 earthquakes magnitude 3.0 or
greater in 2015 versus just two or three a year before 2009. A
magnitude 5.0 earthquake in November near Cushing, Oklahoma, the
largest oil storage hub in the United States, renewed concerns a
quake could damage energy infrastructure.
That quake came just two months after a 5.8 magnitude
temblor, the strongest on record for the state.
Production in the STACK and SCOOP may rise if oil prices
keep rising following a deal last month by the Organization of
the Petroleum Exporting Countries (OPEC) to curb output.
While STACK and SCOOP produce much less water than the
Mississippian Lime formation, where most of Oklahoma's quakes
have occurred, some seismic anomalies have been observed in the
area and are believed to be related to hydraulic fracturing.
"The commission isn't concerned about it, but wants to give
guidelines to make sure they don't grow in magnitude. They're
taking it as a proactive approach to this new emerging formation
in the SCOOP and STACK," said Chad Warmington, president of the
Oklahoma Oil and Gas Association.
A study in May found about 90 percent of earthquakes in
Texas over 40 years were caused by oil and gas activities, and
frequency of those quakes rose in tandem with the shale boom.
(Reporting by Liz Hampton; Editing by Cynthia Osterman)