First research links California earthquakes to oil operations

SAN FRANCISCO - A 2005 spate of quakes in California's Central Valley almost certainly was triggered by oilfield injection underground, a study published Thursday said in the first such link in California between oil and gas operations and earthquakes.

See Full Article

Researchers at the University of California at Santa Cruz, the University of Southern California and two French universities published their findings Thursday in a publication of the American Geophysical Union. The research links a local surge in injection by oil companies of wastewater underground, peaking in 2005, with an unusual jump in seismic activity in and around the Tejon Oilfield in southern Kern County.

In Oklahoma and other Midwestern states, the U.S. Geological Survey and others have linked oilfield operations with a dramatic surge in earthquakes. Many of those quakes occur in swarms in places where oil companies pump briny wastewater left over from oil and gas production deep underground.

"It's important to emphasize that definitely California is not Oklahoma," lead author Thomas Goebel at the University of California at Santa Cruz said Thursday. "We don't really expect to see such a drastic increase in earthquake occurrences" in California given different oilfield methods and geology in the two areas.

In Kern County, the shaking topped out on Sept. 22, 2005, with three quakes, the biggest magnitude 4.6, researchers said.

Researchers calculated the odds of that happening naturally, independently of the oilfield operations, at just 3 per cent, Goebel said. However, the oilfield operation "may change the pressure on ... faults, and cause some local earthquakes" in California, he said.

Researchers are now studying other areas of the state to see if California's high background level of shakiness is obscuring other seismic activity possibly linked to oilfield activity. California is the country's No. 3 oil-producing state.

The Center for Biological Diversity environmental group, using state figures, estimates that the amount of oilfield wastewater injected underground in California climbed from 350 million barrels in 1999 to 900 million barrels in 2014.

Catherine Reheis-Boyd, president of oil-industry group the Western States Petroleum Association, said the organization is reviewing the study. But she said the study's calls for careful monitoring are consistent with what the group's member companies are already doing.

California on Dec. 10 commissioned Lawrence Berkeley National Laboratory to study the overall potential for oilfield-induced quakes in the state, said Don Drysdale, spokesman for the state Division of Oil, Gas and Geothermal Resources, the main oil regulatory agency. Rules that went into effect last year for some intensive forms of oil production require monitoring for seismic activity.

"In California, of course, we have a lot of natural seismicity here, so it's much more difficult" to establish that an earthquake was caused by oilfield activity than it is in places like Oklahoma, which used to be quiet, said Art McGarr, a seismologist at the U.S. Geological Survey's Earthquake Science Center in Menlo Park, California.

"Nonetheless, I think they made at least a fairly convincing case that these earthquakes were related to fluid injection" by oilfield operators, said McGarr. He called the researchers' analysis "quite careful."



Advertisements

Latest Tech & Science News

  • Researchers sound alarm over millions of tonnes of plastic dumped into oceans

    Tech & Science CBC News
    A team of researchers set off from the southern California city of Los Angeles to the Hawaiian islands on a mission to collect data in the Pacific Ocean which might help find routes taken by millions of tonnes of plastic dumped into the seas each year. Source
  • Former astronaut, U.S. senator John Glenn dead at 95

    Tech & Science CBC News
    John Glenn, whose life took him to the celestial heights as the first American to orbit the Earth, then into the trenches of congressional infighting as a longtime Democratic senator, before he re-entered space as a 77-year-old, has died. Source
  • John Glenn, first U.S. astronaut to orbit Earth, dies

    Tech & Science CTV News
    WASHINGTON -- John Glenn, whose 1962 flight as the first U.S. astronaut to orbit the Earth made him an all-American hero and propelled him to a long career in the U.S. Senate, died Thursday. The last survivor of the original Mercury 7 astronauts was 95. Source
  • Sask. researcher helps ID feathered dinosaur tail trapped in amber

    Tech & Science CTV News
    REGINA - A Canadian researcher has helped identify a 99-million-year-old dinosaur tail which has been preserved in amber. The specimen was purchased from a Myanmar amber market in 2015 by a Chinese academic who recognized its potential. Source
  • It's already happening: Hundreds of animals, plants locally extinct due to climate change

    Tech & Science CBC News
    It may be tempting to take comfort in the idea that big changes related to climate change are decades away. But a new study from the University of Arizona has found that local extinctions related to global warming have already occurred in almost half of the species studied. Source
  • Feathered dinosaur tail found trapped in amber

    Tech & Science CBC News
    In 2015, scientist Lida Xing came across a beautiful and curious piece at an amber market in Myitkyina, Myanmar, likely destined to become a piece of jewelery. Trapped inside the yellow piece was a feather that others had overlooked as belonging to a plant. Source
  • 6.8 M earthquake strikes off north coast of California

    Tech & Science CBC News
    A 6.8 magnitude earthquake struck off the north coast of California at around 6:50 a.m. PT Thursday, the U.S. Geological Service reported. The quake struck roughly 165 kilometres west of Eureka. No tsunami alert was issued and no damage has been reported. Source
  • Giraffes threatened by extinction, put on watch list

    Tech & Science CBC News
    The giraffe, the tallest land animal, is now at risk of extinction, biologists say. Because the giraffe population has declined by nearly 40 per cent in just 30 years, scientists put it on the official watch list of threatened and endangered species worldwide, calling it "vulnerable. Source
  • Archaeologists examine Indigenous site dating back 2,200 years on Exploits River

    Tech & Science CBC News
    An archeological dig has uncovered material that dates back more than 2,000 years on the Exploits River. Laurie Maclean, an archeologist, and Don Pelley, dig assistant, spent two weeks in November sifting through mud, clay and dirt on the edge of the river in search of items that belonged to the Groswater Paleoeskimos. Source
  • Polar bears scavenging more orca-killed bowhead whales: study

    Tech & Science CTV News
    As more killer whales move into the Arctic, at least one population of polar bears is learning how to make the best of no longer being at the top of the food chain. Research presented at a scientific conference in Winnipeg this week suggests the bears are beginning to take advantage of the beached remains of an orca's favourite food - bowhead whales. Source