New Study Suggests Disturbing Link Between Fracking and Large Earthquakes

New Study Suggests Disturbing Link Between Fracking and Large Earthquakes

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Kevin Samson
Activist Post

There has been an ongoing battle between researchers and the natural gas
and oil industries over whether or not hydraulic fracturing (fracking)
is definitively leading to an increase in earthquake activity.

Since September of 2010, nearly 1,000 earthquakes have rattled Arkansas
and the area around the New Madrid Fault Line. Previous to this,
Arkansas had a total of 38 quakes in 2009. Yet two cities, Greenbrier
and Guy had a swarm of 30 small earthquakes in a four-day period in early 2011, which paralleled fracking activity in the same area.



This uptick was echoed next-door in Oklahoma, where during roughly the
same period, the state saw an increase in earthquakes from 50 per year
to over 1,000 in 2010. The accumulating present-day data is also
mirrored by earlier government research, as you will see below.

Now, a study has appeared from The Geology Society of America, which
investigated the largest of the quakes that rattled Oklahoma and 17
other states in November of 2011. While supporting the research of
others in establishing a causal link between fracking and earthquakes,
they appear to have found another even more troubling aspect to the
data.


Hydraulic fracturing (fracking) pumps water and
chemicals into the ground at a pressurized rate exceeding what the
bedrock can withstand, resulting in a microquake that produces rock
fractures. Though initiated in 1947, technological advances now allow
horizontal fracturing, vastly increasing oil and gas collection. (Source)



The U.S. Army's Rocky Mountain Arsenal established an uncomfortable link
between their own operations and rising earthquake activity near
Denver, Colorado back in the early 1960s:
<blockquote class="tr_bq">
According to the RMA, “The Rocky Mountain Arsenal deep injection well
was constructed in 1961, and was drilled to a depth of 12,045 feet” and
165 million gallons of Basin F liquid waste, consisting of “very salty
water that includes some metals, chlorides, wastewater and toxic
organics” was injected into the well during 1962-1966. </blockquote>
<blockquote class="tr_bq">
Why was the process halted? “The Army discontinued use of the well in
February 1966 because of the possibility that the fluid injection was
“triggering earthquakes in the area,” according to the RMA. (Source)</blockquote>



They drew this conclusion even after the EPA stated that this method of
deep injection was safe. Over the decades that would follow, both the
U.S. Army Corps of Engineers and the U.S. Geological Survey would
accumulate data that showed a link between fracking and underground
instability that can trigger earthquakes.

One of the first large studies of an Oklahoma earthquake swarm which
began early in 2011 was conducted by the Oklahoma Geological Survey. The
results were released in August of 2011 and conclude with a probable
correlation within this event, as well as citing a connection made from
the historical record:
<blockquote class="tr_bq">
The strong correlation in time and space as well as a reasonable fit to a
physical model suggest that there is a possibility these earthquakes
were induced by hydraulic fracturing. </blockquote>
<blockquote class="tr_bq">
Our analysis showed that shortly after hydraulic fracturing began small
earthquakes started occurring, and more than 50 were identified, of
which 43 were large enough to be located. Most of these occurred within a
24 hour period after hydraulic fracturing operations had ceased. There
have been previous cases where seismologists have suggested a link
between hydraulic fracturing and earthquakes, but data was limited, so
drawing a definitive conclusion was not possible for these cases. The
first case occurred in June 1978 in Carter and Love Counties, just south
of Garvin County, with 70 cases in 6.2 hours. The second case occurred
in Love County with 90 earthquakes following the first and second
hydraulic fracturing stages. [Nicholson and Wesson, 1990] (Source)</blockquote>
Given
the aforementioned documentation by the U.S. Army and the U.S.
Geological Survey, the data is beginning to look conclusive.

However, there is one more concern that is addressed in the most recent
study conducted by the Geological Society of America, a non-profit
organization with tens of thousands of members from nearly 100
countries. According to the abstract of this study, which looked most
specifically at the largest earthquake reported, a 5.7 event that
occurred in November (after the study cited above):
<blockquote class="tr_bq">
Significant earthquakes are increasingly occurring within the
continental interior of the United States, including five of moment
magnitude (Mw) ≥ 5.0 in 2011 alone. Concurrently, the volume of fluid
injected into the subsurface related to the production of unconventional
resources continues to rise. Here we identify the largest earthquake
potentially related to injection, an Mw 5.7 earthquake in November 2011
in Oklahoma. The earthquake was felt in at least 17 states and caused
damage in the epicentral region. It occurred in a sequence, with 2
earthquakes of Mw 5.0 and a prolific sequence of aftershocks. </blockquote>
<blockquote class="tr_bq">
(...) </blockquote>
<blockquote class="tr_bq">
Subsurface data indicate that fluid was injected into effectively sealed
compartments, and we interpret that a net fluid volume increase after
18 yr of injection lowered effective stress on reservoir-bounding
faults. Significantly, this case indicates that decades-long lags
between the commencement of fluid injection and the onset of induced
earthquakes are possible, and modifies our common criteria for
fluid-induced events. The progressive rupture of three fault planes in this sequence suggests that stress changes from the initial rupture triggered the successive earthquakes, including one larger than the first [emphasis added]. (Source)</blockquote>
This is a worrisome conclusion which seems to indicate that even if
fracking is halted, earthquake activity can continue as a result of
previous activity, and earthquake magnitude can increase over time.

Much more studying needs to be done to confirm the above, and the full
results still need to be scrutinized by the scientific community.
However, in light of the worries already surrounding the historically
dangerous New Madrid Fault Line,
we should hope that definitive action is taken sooner rather than later
to halt a process that is dubious at best, and cataclysmic at worst.

Source:-
http://www.activistpost.com/2013/04/new-study-suggests-disturbing-link.html