Environment, Education, Energy: Policy to People

Mapped: Oklahoma’s Earthquake Swarm (UPDATED 02/17)

More than a dozen small earthquakes shook central Oklahoma over the weekend, including several temblors that were 3.0-magnitude or higher, which people can generally feel. Did you feel the shaking? Find details on the earthquake near you. » UPDATED: 02/17/2014

The tremors are the latest in a swarm of quakes the U.S. Geological Survey says may be linked to waste fluid disposal wells used by the oil and gas industry. The swarm began in 2009, and has included more than 200 magnitude 3.0 or greater temblors. The “unusual” earthquakes don’t appear to be natural, and USGS seismologist Bill Leith has issued a warning of increased quakes throughout central Oklahoma.

StateImpact has mapped the earthquakes from 2009 to present, using data from the Oklahoma Geological Survey. Click around the map to see details on the time, location and magnitude of earthquakes near you.

Independent geophysicists have also linked earthquakes in Oklahoma — and other states — to disposal wells, which are used to store toxic drilling fluid deep underground, where it won’t contaminate water supplies. The swarm includes Oklahoma’s largest earthquake, a 5.7-magnitude temblor that shook the ground near Prague in November 2011, which some geophysicists say could be the largest linked to drilling activity.

StateImpact’s map shows earthquakes with a detectable magnitude recorded in Oklahoma from Jan. 1, 2009 to Feb. 17, 2014, and was built with data compiled by the Oklahoma Geological Survey. The red dots represent 3.0-magnitude or greater quakes, which people nearby are likely to have felt.

StateImpact Oklahoma is a partnership among Oklahoma’s public radio stations and relies on contributions from readers and listeners to fulfill its mission of public service to Oklahoma and beyond. Donate online.


  • Kevin
  • Name

    Seriously, why does everything get blamed on the oil and gas companies!?!

    • Denise

      Because they make money from it lol

    • miner

      well, apologist, it’s because they are causing this…get it?

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      I don’t think most of our commenters are blaming everything on oil and gas companies.

  • DoobZilla

    Well, “Name,” the reason that they are being blamed in this instance is because of the sheer fact that coincidences rarely exist in nature. The fact that Oklahoma’s history of earthquakes was mostly negligible until these last few years and has only recently become an issue shortly after “fracking” became commonplace in the Natural Gas industry might have something to do with this “bias.”

    While there is no conclusive proof, when a geophysicist says that these earthquakes are, “almost certainly manmade,” I kind of tend to take notice…

    Now, if this particular geophysicist is wrong, then so be it. But shouldn’t we kind of err on the side of caution here? For sixty-some-odd years, the tobacco industry said that smoking wasn’t bad for your health, but the empirical evidence always suggested otherwise… That might not be the best example, but it does point out the fallacy with always believing and never questioning what someone, who is trying to sell you something, says…

    • rhomin57

      Alcoholism goes hand in hand with tobacco smoking, but Govt doesn’t pick on the Alcohol companies. Why, because the Alcohol companies are huge lobbyists, and tobacco companies aren’t. Complain about a drunk that ran down some little kid why don’t ya. Doesn’t happen due to a cigarette.

      • peace55

        Now there’s an angry smoker! We are talking about earthquakes that can destroy property and lives in an instant and he can only think about the bum wrap tobacco companies get. Cigarettes can kill, but at least we all have a choice about it!

      • Denise

        More money in oil

    • Kyle Dobbs

      Doobzilla, they are beginning to have the same accusations in Texas. They believe their quakes are caused by all wells–oil, natural gas, and disposal wells. It makes no sense how wells have anything to do with this.

  • Naturalist1

    Seriously, why not, as statistically there’s no other logical source.

    • Denise

      Then the 5% (rich) wouldn’t make money . They control our economy by what they invest in . Oil makes them money :-)

  • Andrea

    I wish people would quit peeing in their pants about these earthquakes. Ladies and gentleman of Oklahoma we live on a fault line. We’ve had earthquakes before we started to drill baby drill and we will have earthquakes after we’ve finished drilling. Missouri lives on a fault line where a massive earthquake made the Mississippi River flow north for a short period of time. Why are we making a big fuss about it…… it’s easier than ever to get data quicker than ever. We don’t have to wait for our neighbor from 5 miles over to tell us he might have felt something. We aren’t as rural as we were 100 year ago or even 50 years ago. The areas that lie on our fault lines weren’t heavily populated until recently so of course we are going to have more reports of people feeling earthquakes because there are more people to feel and report them to news outlets. The report posted by Kevin is an excellent report that says these recent earthquakes (particularly the Praque sequence of earthquakes in 2011) were the result of natural seismic activity.

    • Denise

      There were no earthquakes mentioned in the 60′s or 70′s or 80′s when I lived there . Oklahoma may be on a fault line but was awakened by fracking period / cause and effect .
      Fracking is the cause and earthquakes are the effect.

      • r262

        Technically, it is not the fracking. It is the water waste produced from it and how it is disposed of that is in question. Ironically, in an attempt to protect the environment (prevent water contamination) another problem may have been created.

        • http://mywag.wordpress.com/ my wag

          r262, thank you for being clear and concise. Blaming waste water injection doesn’t mean anyone hates energy companies. It just means what it means. The quakes are the result of high pressure waste water injection into the ground. It is done to: #1. Hide an ugly problem…filthy, poisonous waste water. #2. It is the cheapest way to frack and accomplish 1st objective. #3. It has been happening for years. Arkansas and Texas have been in the news for this beginning a few years ago.

          If your causing a problem: Own it, like a true American. Don’t be a ‘fraidy cat’. Evasive and avoidance of responsibility are 2 despicable attributes of the way some businesses are run. And that’s a shame.

        • http://westchestergasette.blogspot.com/ WCGasette

          Technically, the fracking waste must be disposed of…so “technically” fracking IS the problem. These disposal/injection wells are located near areas of oil and gas activities since it is so toxic and the closer the injection wells the less money is spent on transportation.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      Oklahoma has always had earthquakes, that’s true. And Oklahoma’s population is definitely growing. However, the number of recorded earthquakes IS increasing.

      And while the OGS’s March 2013 report about the 2011 quake in Prague suggested it fit the pattern of natural quakes, other seismologists — and more recent studies — suggest it was triggered by oil and gas activity.

      The most recent warning from the USGS, issued in October 2013, says Oklahoma’s 2009-2013 swarm of quakes — which includes the Prague sequence — doesn’t appear to be natural.

      Here’s what USGS seismologist Bill Leith says in the warning.

      “We’ve statistically analyzed the recent earthquake rate changes and found that they do not seem to be due to typical, random fluctuations in natural seismicity rates,” said Bill Leith, USGS seismologist … The analysis suggests that a contributing factor to the increase in earthquakes triggers may be from activities such as wastewater disposal–a phenomenon known as injection-induced seismicity … This “swarm” includes the largest earthquake ever recorded in Oklahoma, a magnitude 5.6 that occurred near Prague Nov. 5, 2011. It damaged a number of homes as well as the historic Benedictine Hall at St. Gregory’s University, in Shawnee, Okla.

      Here’s a link to the USGS warning: http://on.doi.gov/HgLnmk

      These quakes are still relatively small — though people were hurt in the Prague quake — so the risk of injury is obviously small, but there are implications for property damage, building codes, and insurance coverage.

      • Sharon Sims-Belvin

        Joe…..you’ll have to show them in graph form. It would be very simple to create a graph for a few areas….Oklahoma, Texas(has had 15-20 in the past month) and a few other areas…maybe Arkansas and Colorado. Graph out quakes over the past..say 50 years. List when fracking began in those areas and when the earthquakes have been. We’ve graphed it in Texas and the results are impossible to dispute. It is very clear that the quakes are most definitely related to fracking. Ever “where” the quakes are……they are surrounded by frack sites and injection wells.

        • http://stateimpact.npr.org/oklahoma Joe Wertz

          A graph is a good idea! It’s a bit tricky to compare states as far as fracking goes, because not every state keeps the same records — or in the same format.

          Have a link to your graph in Texas?

          • Sharon Sims-Belvin

            Sharon Wilson has a blog….TxSharon BlueDaze Reform…She has graphs that compare earthquakes and fracking history in this area. She also has a tremendous amount of info on that blog. You should check it out and while you’re there, you should view the video of a blowout of chemical laced frack water in Denton, Tx. that happened a few months ago.

  • Denise

    Fracking causes it due to the shift in the earths plates being shifted done by oil companies :-)
    I grew up there and we had none in the 60′s 70′s or 80″s . None in the 90′s that I know of either . Just since fracking hmmm

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      Just to be 100% clear: None of the seismologists are suggesting that fracking itself is causing the quakes — it’s related to the wells that store waste fluid from drilling.

      But hydraulic fracturing does produce a lot of waste fluid, which is injected into those wells. “Fracking-related” is probably more accurate.

      • BILL M.


        • BILL M.


          • miner

            Hey grandpa, is everything is Obama’s fault?–quit regurgitating Fox bile all over this thread–go post in a relevant thread…sheesh you republicans find a conspiracy behind every tree–that’s why I left the Oklahoma in the 70′s– full of closed-minded extremists…ugh

          • http://stateimpact.npr.org/oklahoma Joe Wertz

            Let’s try our best to keep everything civil and constructive here, folks. No need for name-calling! StateImpact is going into our third year, and I’ve never had to delete any non-spam comments. Let’s keep it that way, and avoid the problems that plague other news site comment sections. Sound good?

      • http://westchestergasette.blogspot.com/ WCGasette

        Horizontal wells in shale cannot be fracked without creating tons of toxic waste. Injection sites are near these wells. But let’s not forget that even the USGS admits that extraction of the oil and gas from horizontal wells during the completion phase can create seismicity. There could be no extraction without “fracking.” All roads lead to the FRAC job.

    • transplanted okie

      Denise,fracking has been going on sine the 60′s. Hmmmmm!!!!!!!!!

  • Eddie M Reese

    I would like to see data from other states where fracking is occurring and if there is an increase in earthquake activity.

    • GeoSci

      Finally somebody speaks up in support of the actual scientific process! The way these people carry on one would think that Oklahoma is the only state that practices formation fracturing. If they are seriosly considering this as the primary cause of Oklahoma’s faults activating (there’s literally hundreds if not thousands of small faults criss-crossing the state) they really need to examine the occurances of earthquakes in other states where fracturing is practiced (pretty much all of them). Especially those with multiple fault lines.

      • http://stateimpact.npr.org/oklahoma Joe Wertz

        Our work obviously focuses on Oklahoma, but this has been studied in other states, too. Again, this phenomenon can be fracking-related, but it’s generally not fracking itself. Papers have been published supporting evidence of “induced seismicity” in California, Colorado, Arkansas and Texas. There may be others, but those are the ones that come to mind.

    • richardguldi

      Look up Azel TX. 19 quakes in November. None in history previous to when frackiing began.

  • JD

    If Fracking is 1 of the main contributors to these quakes, how is it that Kansas is unaffected? Because there is major Fracking goin on in Kansas for the last few years as well as Oklahoma.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      That’s a great question, JD. I’ll ask some seismologists today. Kansas certainly has a lot of disposal wells. Maybe there’s a geological difference in the two states? I’ll report back when I find out.

      • JD

        Thanks Joe! I am truely curious. I know there is a lot of Fracking in Southern KS, which I would assume has many geological similarities as Northern OK (where it seems the “swarms” are currently located).

    • jr023

      Pennsylvania also has major fracking going on

  • r262

    I am concerned that politics will prevent us from honestly looking at this situation objectively. One one end we have people screaming “fracking!” and the other a complete denial that there is a possibility that the waste water disposal wells may be causing these quakes.

    We all need to be open-minded and encourage research in this area. Then perhaps a new way of proceeding can be discoveted that will not cause the quakes and still be beneficial to the oil and gas companies.

    P. S. I am a staunch conservative, but I am not for turning a blind eye to what could be harmful to citizens to benefit big business. There is too much crony capitalism in both parties.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      Great comments! Your perspective seems sensible to me.

  • Horse with No Name

    I wouldn’t be too quick to base your assertions off of Keranen’s work. She and her co-authors had to invent faults surrounding the Wilzetta in order for their theory to work (faults which she claims to have seen on “proprietary 3D seismic,” meaning no one else can check her work), and they completely ignored the fact that the precursor quake in 2010 had arguably no influence by disposal wells (there hadn’t been an active disposal well in the area for almost 15 years prior).

    There may be good arguments for injection wells causing this rise in seismic activity, but Keranen’s ain’t it.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      That’s a heck of a claim, Horse. Anything to back it up? She co-authored the Prague papers with scientists at Columbia and the U.S. Geological Survey, and it was vetted and published in two pretty prestigious publications — Geology and Science.

  • Doug in Florida

    I recently made a semi-tongue-in-cheek comment in my new blog (http://reflectionsindarkglass.blogspot.com) suggesting that the earthquake swarm rattling my Oklahoma relatives might reflect a positive effect of fracking. Since we know that the biggest quake on record in North America, the New Madrid quake of the early 19th Century, took place before drilling and/or fracking, and that it was caused by the release of built up tension in the tectonic plates, is it possible that injection wells are lubricating the tectonic plates along fault lines and allowing the gradual release in small bursts of the accumulated tensions and will thus help prevent the build-up of the kind of tension that results in a major quake? Rattling windows over a long period of time would be preferred to knocking down entire major cities in one cataclysmic burst, I should think.

    • http://westchestergasette.blogspot.com/ WCGasette

      The Oklahoma Earthquake Swarm is a “Positive” effect of Fracking? Think again. It’s a FANTASY according to the USGS:


      “You can prevent large earthquakes by making lots of small ones, or by “lubricating” the fault with water
      FICTION: Seismologists have observed that for every magnitude
      6 earthquake there are about 10 of magnitude 5, 100 of magnitude 4,
      1,000 of magnitude 3, and so forth as the events get smaller and
      smaller. This sounds like a lot of small earthquakes, but there are
      never enough small ones to eliminate the occasional large event. It
      would take 32 magnitude 5′s, 1000 magnitude 4′s, OR 32,000 magnitude 3′s
      to equal the energy of one magnitude 6 event. So, even though we always
      record many more small events than large ones, there are far too few to
      eliminate the need for the occasional large earthquake. As for
      “lubricating” faults with water or some other substance, if anything,
      this would have the opposite effect. Injecting high- pressure fluids
      deep into the ground is known to be able to trigger earthquakes—to cause
      them to occur sooner than would have been the case without the
      injection. This would be a dangerous pursuit in any populated area, as
      one might trigger a damaging earthquake.”

  • Mike

    My question is – when will the studies become serious enough that they can used as evidentiary support the next time a 4 or 5 point temblor causes actual structural damage (like the 5.6 in 2011)? I can’t wait for the day the litigation opens up on the fracking industry. It will be as beautiful as seeing big tobacco take one on the chin.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      By “evidentiary support,” I’m assuming you mean in a lawsuit? I’m not sure what the threshold is for use in courtroom, but I know of at least three peer-reviewed studies in major science publications that make the link.

      However: Making the case for a general link is quite a bit different than proving that Well A caused Earthquake B on Day C that caused damage to Building D. At least that’s what the scientists tell me.

      Interesting that you made the tobacco parallel, which seismologists have made to me in interviews, too. Health scholars are confident that smoking causes cancer, but it’s nearly impossible to prove that a particular cigarette or company was responsible for one person’s tumor. That hasn’t stopped lawsuits or regulation of the tobacco industry, of course, but that’s been a slow, political, PR process as much as anything.

  • Concerned1111

    I took some time to read most of the comments below….and wanted to put my 2 cents in as a person who actually lives in the area (OK) of the recent swarm of earthquakes in Feb. I experienced the quakes first hand, I do not have tech knowledge which by making this statement some may already write me off. Anyway, here is what I witnessed, we had a rig go up in sight distance from our place, a few days in, we heard our first “boom” following that more activity, than the big weekend with Sunday – 2/16 topping it off for me, from 5:30pm – 2am every 20-30 min. I felt something, heard something, or both (enough to rock my couch on cement and my bed….interesting enough, guess what, that rig stopped drilling (yes, you can hear it, noisy things) and it pulled up shop. They say no drilling was happening when the swarm of quakes hit, a statement from the oil company to the newspaper but I know different. Since they have left, we have not had any quakes near our place….Yes it did do damage to our house with all the “little” rumbles. You don’t need to wait for a BIG quake to have damage if the swarm is consistent. This was this first time we have had earthquakes (that we noticed) at our home and have lived here over 25 years.

    • http://stateimpact.npr.org/oklahoma Joe Wertz

      What area do you live in, Concerned? I’d love to talk to you! My email is jwertz@stateimpact.org if you don’t feel comfortable giving details here.

    • http://westchestergasette.blogspot.com/ WCGasette

      What you are writing sounds very similar to what many have experienced in the Azle, TX quakeswarm. These smaller earthquakes do cause damage to property. And they may be the precursor to a very strong earthquake.

    • Kyle Dobbs

      Concerned, the drilling would not have caused a quake. You’re a virgin to the oilfield. My family has been in the oilfield all my life. The drilling does not case quakes. The only shaking felt during the drilling is on the floor around the rotary-table.



  • disqus_OUqwS070WZ
  • disqus_OUqwS070WZ

    This couldn’t be an anti-o&g biased site could it? Ummmmm??

About StateImpact

StateImpact seeks to inform and engage local communities with broadcast and online news focused on how state government decisions affect your lives.
Learn More »