I am not a genius but I don't see how anyone with any common sense could read this article with all the qualifiers (I took the liberty of highlighting them for you) and come to the conclusion in the title of Mr. Ritters article, unless your goal was to help with the re-election of President Obama, an ardent believer in the evils of fossil fuels.
Read it yourself and make your own judgement!
Oil,
gas production blamed for spike in quakes
By MALCOLM RITTER
Associated Press
NEW YORK -- Oil and
gas production may
explain a sharp increase in small earthquakes in the nation's midsection, a new
study from the U.S. Geological Survey suggests.
The rate has jumped
six-fold from the late 20th century through last year, the team reports, and
the changes are "almost
certainly man-made."
Outside experts were split in their opinions about the report, which is not yet published but is
due to be presented at a meeting later this month.
The study said a relatively
mild increase starting in 2001 comes from increased quake activity in a methane
production area along the state line between Colorado and New Mexico. The
increase began about the time that methane production began there, so there's a
"clear possibility"
of a link, says lead author William Ellsworth of the USGS.
The increase over the
nation's midsection has gotten steeper since 2009, due to more quakes in a
variety of oil and gas production areas, including some in Arkansas and
Oklahoma, the researchers say.
It's not clear how the earthquake rates might be related
to oil and gas production, the study
authors said. They note that others have linked earthquakes to injecting huge
amounts of leftover wastewater deep into the earth.
There has been
concern about potential
earthquakes from a smaller-scale injection of fluids during a process known as
hydraulic fracturing, or fracking, which is used to recover gas. But Ellsworth said Friday he is
confident that fracking is not responsible for the earthquake trends his study
found, based on prior studies.
The study covers a
swath of the United States that lies roughly west of Ohio and east of Utah. It
counted earthquakes of magnitude 3 and above.
Magnitude 3 quakes
are mild, and may be felt by only a few people in the upper floors of
buildings, or may cause parked cars to rock slightly. The biggest counted in
the study was a magnitude-5.6 quake that hit Oklahoma last Nov. 5, damaging
dozens of homes. Experts
said it was too strong to be linked to oil and gas production.
The researchers
reported that from 1970 to 2000, the region they studied averaged about 21
quakes a year. That rose to about 29 a year for 2001 through 2008, they wrote,
and the three following years produced totals of 50, 87 and 134, respectively.
The study results
make sense and are likely
due to man-made stress in the ground, said Rowena Lohman, a Cornell University
geophysicist.
"The key thing
to remember is magnitude 3s are really small," Lohman said. "We've
seen this sort of behavior in the western United States for a long time."
Usually, it's with geothermal energy, dams or prospecting. With magnitude 4 quakes, a person standing on top
of them would at most feel like a sharp jolt, but mostly don't last long enough
to be a problem for buildings, she said.
The idea is to
understand how the man-made activity triggers quakes, she said. One possibility
is that the injected fluids change the friction and stickiness of minerals on
fault lines. Another concept is that they change the below-surface pressure
because the fluid is trapped and builds, and then "sets off something
that's about ready to go anyway," Lohman said.
But another expert was not convinced of a link to oil and
gas operations.
Austin Holland, the
Oklahoma state seismologist, said the new work presents an "interesting
hypothesis" but that the increase in earthquake rates could simply be the result of natural
processes.
Holland said clusters of
quakes can occur naturally, and that scientists do not yet fully understand the
natural cycles of seismic activity in the central United States. Comprehensive
earthquake records for the region go back only a few decades, he said, while
natural cycles stretch for tens of thousands of years. So too little is known to rule out
natural processes for causing the increase, he said.
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