TPT July 2015

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70 July 2015
Global Marketplace
Oil and gas
The idea that injecting water
deep into the ground can trigger
earthquakes, talked about
for decades, moves beyond
speculation
Seismic activity in Texas near the Dallas-Fort Worth area
has increased substantially recently. Kansas, Colorado, New
Mexico and Ohio have all experienced more frequent quakes
in the last year. But Oklahoma is by far the worst-hit state,
according to a study released on 23 April by the US Geological
Survey (USGS). Oklahoma in 2014 had more earthquakes of
magnitude 3 or higher than California, further evidence of a
huge increase recorded in recent years.
For the first time the USGS has published results of a
mapping of areas in the eastern and central United States
hit by earthquakes thought to be triggered by human activity.
The areas highlighted on its map “are located near deep fluid
injection wells or other industrial activities capable of inducing
earthquakes,” the study authors said.
In an interview with the Los Angeles Times, Mark Petersen,
chief of the USGS National Seismic Hazard Project, said
the pattern of increased quakes is troubling. He told Rong-
Gong Lin II, Jon Schleuss and Thomas Suh Lauder, “These
earthquakes are occurring at a higher rate than ever before,
and pose a much greater risk and threat to people living
nearby.” The reporters wrote that the release of the map
“comes as officials are coming to terms with the idea” that
wastewater disposal following oil and gas extraction by
hydraulic fracturing, or fracking, is causing more earthquakes.
The wastewater generated by this method – which involves
shooting a high-pressure mix of water, sand, and chemicals
deep underground – is often forced underground as well,
and can trigger earthquakes along faults that haven’t shifted
in a very long time. (“Man-made Earthquakes Increasing in
Central and Eastern US, Study Finds,” 23 April)
Another entity, the Oklahoma Geological Survey, said on 21
April that the sharp rise in quakes in the state is “very unlikely
to represent a naturally occurring process,” since they occur
in the same area that saw a huge jump in wastewater disposal
over the last several years. The seismicity rate in 2013 was 70
times greater than the background seismicity rate observed in
Oklahoma prior to 2008, state officials said.
Larger and more frequent quakes
To put the increase in both size and frequency of human-
induced earthquakes – and their threat to public safety – into
perspective, the Times cited a magnitude 5.6 earthquake
believed to have been caused by wastewater injection that
hit near Prague, Oklahoma, in 2011, injuring two people and
destroying 14 houses. That same year, a 5.3 earthquake
struck a remote part of Colorado, near the town of Trinidad
close to the New Mexico border, which the USGS said was
also triggered by wastewater injection.
In another instance, from the 1960s, according to a study
reviewed in the journal Science at the time, many scientists
concluded that injection of chemical-waste fluid in the Denver
Basin triggered seismic activity.
› For an example farther afield, Messrs Lin, Schleuss and
Lauder called attention to the desert town of Gazli in the
former Soviet republic of Uzbekistan, where earthquakes were
once rare occurrences. Like Oklahoma, this region was some
distance from the boundaries of the giant tectonic plates whose
crashes create the huge quakes well known in California.
Then, in 1976, two big earthquakes hit the Gazli area. And
a magnitude 7 quake struck in 1984, killing one person and
injuring more than 100. As noted by the Los Angeles Times,
“Scientists writing in the bulletin of the Seismological Society
of America at the time suggested that the quake could have
been induced by human activity at the gas field.”
Some 150 million Americans are
at risk from earthquakes and the
economic toll of quake damage is
roughly $4.5 billion a year
“Nearly half of all Americans – 150 million people – are
threatened by possibly damaging shaking from earthquakes.”
Rong-Gong Lin II, one of the three the Los Angeles Times
reporters mentioned in the previous item, was quoting
scientists at a meeting of the Seismological Society of
America to present the results of another study. Contributors
include attachés of the US Geological Survey (USGS).
(“Nearly Half of Americans Threatened by Earthquakes,
Study Finds,” 22 April). That figure – 150 million people,
from all 50 states and Puerto Rico – represents a jump from
1994, when the Federal Emergency Management Agency
estimated that 75 million Americans in 39 states were at
risk from earthquakes. The sharp increase in exposure to
quake damage is largely traceable to population increases
in areas prone to earthquakes, particularly California, said
William Leith, a study co-author and senior science advisor for
earthquake and geologic hazards at USGH.
A dollar value can be put on the threat. Authorities calculate
the average financial loss to earthquakes in the contiguous 48
states (excluding Alaska and Hawaii) to be roughly $4.5 billion
a year, mainly in California, Oregon and Washington state.
“Earthquakes remain an important threat to our economy,”
Kishor Jaiswal, a research contractor for the USGS, said in
a statement.
Security expert: the petrochemical
sector of the Middle East, in
particular, should be on alert
against cyber assaults
Andrew Wadsworth, head of process control security at the
defence technology company Lockheed Martin (Bethesda,
Maryland), is concerned that the nations of the GCC – the