Register

Peak Oil is You


Donate Bitcoins ;-) or Paypal :-)


Page added on June 20, 2015

Bookmark and Share

The faster we pump wastewater into the ground, the greater our earthquake risk

The faster we pump wastewater into the ground, the greater our earthquake risk thumbnail

Injecting wastewater into the ground may be an effective way of disposing of salty fluids created through oil and gas production, but it also comes with a perilous side effect: earthquakes. Now, researchers have found that the rate at which we dispose of this liquid may greatly impact the chance that one of these quakes will occur. The faster we inject this water into the ground, the higher likelihood of induced Earth rumblings.

For years, researchers have known that humans can at least partially cause seismic activity. Whenever fluid is added to or withdrawn from the ground, the state of stress on the crust changes. And if that fluid pressure changes inside a fault, friction can decrease, causing the two sides of the fault to push away from each other. Wastewater and fluid injection, dam and reservoir construction, mining, and hydraulic fracturing all contribute to these pressure changes.

“It’s really only a smaller subset of injection wells that are linked to earthquakes.”

Fluid injection wells are important tools for the oil industry. They help dispose of saltwater byproducts from oil and gas activities, as well as pump fluids into existing oil reservoirs — increasing pressure and consequently boosting oil production. These wells are similar to fracking wells, which also inject fluids into the ground to fracture shale rocks and release natural gas. However, wells used for oil recovery inject fluids for years or decades at a time, while fracking wells only inject fluids for a few hours or days.

Experts have known about wastewater injection wells’ ability to trigger quakes for some time, but they’ve been unsure about which wells are the most to blame. “Many factors [of these wells] have been proposed that could contribute to earthquakes: the volume of water injected, the depth of injection, the closer you are to faults,” says George Choy, a research geophysicist at the USGS, who was not involved in the study. “If you can determine which ones are more important, you can prioritize controlling them.” Now, a new study published in Science has parsed these factors, finding that wells with the highest injection rates are twice as likely to be associated with earthquakes than lower-performing wells.

“The idea was to look at this on a broad scale,” study author Matthew Weingarten, a doctoral student at University of Colorado-Boulder, tells The Verge. “It’s really only a smaller subset of injection wells that are linked to earthquakes, so we wanted to try to figure out if there is some kind of well operation that increases the likelihood.”

Weingarten and his research team catalogued the production rates of 180,000 injection wells located between Colorado and the East Coast. They found the wells that pumped more than 300,000 barrels of wastewater into the ground per month were statistically associated with earthquakes. Wells that pump that much wastewater are considered “high rate”; about 18,000 wells — mostly in Oklahoma and Texas — were associated with the most seismic activity.

“Since this is a process that appears to be controllable, you could mitigate the effects.”

“We understand the physics of induced seismicity pretty well,” says Weingarten. “If you increase absolute pressure, you’re going to have an induced earthquake; the physics show these high-rate injection wells preserve the ambient fluid pressure over a larger magnitude than lower-rate wells.”

Weingarten notes that numerous factors were considered, including the wells’ total volume production and proximity to fault lines, but injection rates stood out. He suggests policy makers and regulators could maybe manipulate these rates to lessen induced earthquakes, though he isn’t making any formal recommendations.

Financial incentives may hinder attempts to limit the rate of wastewater injection. Typically, only 30 percent of oil can be extracted from a mature reservoir, but fluid injections increase oil recovery to between 50 and 70 percent. Still, Choy agrees that lowering injection rates may be something to consider, as the number of earthquakes associated with injection wells have increased over the past few decades. “Since this is a process that appears to be controllable, you could mitigate the effects. Obviously there’s some economic imperative to continue the process, but the least you can do is try to [control the rate].”

the verge



5 Comments on "The faster we pump wastewater into the ground, the greater our earthquake risk"

  1. Apneaman on Sat, 20th Jun 2015 3:26 pm 

    Another 4.4 Magnitude Industry Reported Quake in Alberta

    Chevron shuts down operations following seismic event near Fox Creek.

    http://thetyee.ca/News/2015/06/16/Another-Industry-Earthquake/

  2. penury on Sat, 20th Jun 2015 3:43 pm 

    Keep us informed when the governments or people require some thing to be done.

  3. Apneaman on Sat, 20th Jun 2015 5:35 pm 

    ?????????

  4. BobInget on Sat, 20th Jun 2015 7:13 pm 

    http://inhabitat.com/california-oil-refineries-use-94-million-gallons-of-water-a-day-and-nobody-is-stopping-them/

    n California, the ground is dry, cracking, and sinking faster than ever. Farmers are walking away from hundreds of thousands of acres of croplands because there is no water to irrigate. Golf courses and celebrities are shamed for watering their green lawns. But in the fourth year of the worst drought in California’s history, those who wish to save the Golden State have another silent enemy in the fight against the drought: oil refineries.

    Posted note:
    Refineries have lots of waste heat. Enough to desalinate all the sewage or ocean water needed and then some.

    It would e a great PR move to spend a few million becoming water self reliant.

    Refineries work on close margins thus are often unprofitable.
    Switching to natural gas cuts refineries out of the chain. (cuts out tanker trucks and choo choo trains as well)

  5. Makati1 on Sun, 21st Jun 2015 12:47 am 

    The Verge: Part of Vox Media, founded by “political strategist Jerome Armstrong”, “headquartered near Dupont Circle, Washington, D.C.” and funded by “Accel Partners and Comcast amongst others.” And on down the rabbit hole of the corporate propaganda mill. Just enough ‘facts’ to make it seem believable. Should begin: “Once upon a time…”

    “Financial incentives may hinder attempts to limit the rate of waste water injection.” says it all. It’s ALL about money/profits. Capitalism is killing the world. How did the human species go extinct? Capitalist Greed.

Leave a Reply

Your email address will not be published. Required fields are marked *