Earthquakes Induced by Hydraulic Fracturing in Poland Township, Ohio by Robert J. Skoumal, Michael R. Brudzinski, and Brian S. Currie, Published online before print January 2015, doi: 10.1785/0120140168, Bulletin of the Seismological Society of America January 2015
Felt seismicity induced by hydraulic fracturing is very rare, with only a handful of reported cases worldwide. Using an optimized multistation cross‐correlation template‐matching routine, 77 earthquakes were identified in Poland Township, Mahoning County, Ohio, that were closely related spatially and temporally to active hydraulic fracturing operations. We identified earthquakes as small as local magnitudes (ML) ∼1 up to 3, potentially one of the largest earthquakes induced by hydraulic fracturing in the United States. These events all occurred from 4 to 12 March 2014, and the rate decayed once the Ohio Department of Natural Resources issued a shutdown of hydraulic fracturing at a nearby well on 10 March. Using a locally derived velocity model and double‐difference relocation, the earthquakes occurred during six stimulation stages along two horizontal well legs that were located ∼0.8 km away. Nearly 100 stimulation stages in nearby wells at greater distances from the earthquake source region did not coincide with detected seismicity. During the sequence, hypocenters migrated ∼600 m along an azimuth of 083°, defining a vertically oriented plane of seismicity close to the top of the Precambrian basement. The focal mechanism determined for the ML 3 event had a vertically oriented left‐lateral fault plane consistent with the earthquake distribution and the regional stress field. The focal mechanism, orientation, and depth of hypocenters were similar to those of the 2011 Youngstown earthquake sequence that occurred 18 km to the northwest and was correlated with wastewater injection instead of hydraulic fracturing. Considering the relatively large magnitude of the Poland Township events and the b‐value of 0.89, it appears the hydraulic fracturing induced slip along a pre‐existing fault/fracture zone optimally oriented in the regional stress field.
Investigation of Observed Seismicity in the Montney Trend AUTHOR(S) NOT PROVIDED, WERE THEY FROM CAPP? December 2014, BC Oil and Gas Commission
The Montney Trend (Montney) is a 29,850-square-kilometre underground siltstone formation that stretches from the B.C.-Alberta border near Dawson Creek….
The Montney currently has over 1,700 active natural gas wells, nearly all of which are horizontal wells drilled after 2005. …
In order to support unconventional gas development in the Montney, there has been an increase in demand for wastewater disposal capacity. Since 2005, the number of active wastewater disposal wells has increased from 89 to 104, and disposal volumes have increased 60 per cent over the same period [How much fresh water is intentionally contaminated and removed from the surface, permanently?]. Much of the increase is attributable to disposal of flowback fluids from hydraulic fracturing operations. …
….eight new seismograph stations (funded by the Commission, Geoscience BC, and the Canadian Association of Petroleum Producers) were added to the existing two Canadian National Seismograph Network (CNSN) stations to provide more accurate detection and location capabilities. Six went online in August 2013, and two in November 2014. With the new stations the CNSN began recording many more lower magnitude events than previously recorded, enhancing the Commission’s ability to track seismicity. This report’s primary focus is on the investigation into events recorded between August 2013 and
October 2014 in the Montney.
The investigation found that during this period 231 seismic events in the Montney were attributed to oil and gas operations – 38 induced by wastewater disposal and 193 by
hydraulic fracturing operations.
None of the recorded events resulted in any injuries, property damage or loss of wellbore containment. The report finds that events ranging from 2.5 to 4.4 ML may produce actual fault movements in the range of one millimetre to centimetres within the target formation and at depth. [What damage do such events cause to the casings and seals that industry and regulators promise prevent leaks to surface and into groundwater?] …
Currently 450 wells are completed in the Montney each year. These wells average 14 hydraulic fracture stages per wellbore, totaling about 7,500 hydraulic fracture stages for the
investigation period. Injected volumes of hydraulic fracturing fluid range from about 700-3,500 m3 per stage, depending on area and operator. During the investigation period, hydraulic fracturing operations triggered 193 induced events. Therefore, approximately 2.6 per cent of pumped stages triggered events. …
Several [did CAPP edit out how many in exchange for funding or equipment?] instances of casing deformation have occurred within the horizontal portion of shale gas wellbores, but there was no loss of integrity with the wells and no impact on the vertical portions of wellbores. [That’s not what the Septimus diagram in Appendix 3 says (immediately below): “damaged vertical wellbore at 1059m.” How much gas and toxic chemical migration has occurred in the quake areas? Is anyone monitoring for such?] …
Preliminary results indicate induced events triggered by injection at wastewater disposal wells may be mitigated by reducing disposal rate and pressure. Commission water disposal project approvals contain conditions limiting formation pressure to 120 per cent of original formation pressure. [At today’s prices, how long will oil and gas companies mitigate the damages their greed causes? What good are voluntary “best practices” (legally unenforceable) and promises to support regulator recommendations?]
… The effectiveness of mitigation methods for induced seismicity related to hydraulic
fracturing is difficult to assess given the many operational parameters involved.
… Identifying and predicting geohazards that may cause induced seismicity is challenging. In many cases, reflection seismic does not resolve small scale strike slip faulting, which may be susceptible to reactivation and generation of induced seismicity events.
… The Commission is working with the operator on mitigation options.
… The Canadian Association of Petroleum Producers has an induced seismicity [VOLUNTARY, UNINSPECTED, UNENFORCEABLE] operating practice that has recommendations for assessing seismicity potential, drilling design and responding to induced seismicity.
… Several attempts have been made to mitigate the seismicity through reducing volumes and/or pump rates, but results are inconclusive. [Emphasis added to text, hilites and pink added to images]
Fracking caused 220 earthquakes in area: OGC by William Stodalka, January 8, 2015, Alaska Highway News
Fracking caused 11 earthquakes in the Montney basin area surrounding Fort St. John and Dawson Creek between August 2013 and October 2014 that could be felt on the surface, a new B.C. Oil and Gas Commission report states. However, no person or property was injured as a result of those earthquakes, according to the report.
The number of earthquakes is associated with development, according to an oil and gas industry executive. “I would think that the percentage of induced events will be definitely scaled back or forward with activity counts,” said Brad Herald, vice-president of Western Canada Operations for the Canadian Association of Petroleum Producers (CAPP).
The amount of seismic events caused by oil and gas operations that could not be felt on the surface was much higher. There were about 220 seismic events in the Montney in those circumstances. The earthquakes ranged from 1 to 4.4 on the Mercalli scale. The Mercalli scale, which is used in place of the Richter scale, measures earthquake magnitude.
According to the U.S. Geological Service, 1 to 3 magnitude quakes can rarely be felt on the surface. The majority of the earthquakes were in this category. A 3 to 3.9 magnitude quake can be “felt only by a few persons at best, especially on upper floors of buildings.” Less than 10 of these events were in this category. A 4 to 4.9 earthquake can be felt indoors by many, and outdoors by few. It could also wake some people up. Only one or two events were in this category.
The majority of the seismic events — about 84 per cent — came as a result of regular fracking well operations. The other 16 per cent were caused by disposal wells.
But the report stated that two disposal wells created 38 seismic events.
B.C. has 104 disposal wells within its borders.
Hydraulic fracturing — the process used to extract natural gas from deep underground — has long been linked to earthquakes.
“I don’t think it’s a surprise to us,” said Herald. “We monitor those active areas globally in terms of induced seismicity to hydraulic fracturing … we do understand that in some instances there’s induced seismicity related to hydraulic fracturing.”
Last year, his group came forward with a list of operating guidelines to help operators deal with the possibility of earthquakes.
“Industry takes this very seriously and we understand the public has concerns about the issue,” Herald added. “There has been no injuries and no damage to property, but it’s still a felt event, they can be unsettling for people at the surface.”
He further explained that the likelihood of fracking-caused earthquakes would depend on where activities were taking place. In 2012, fracking was linked to earthquakes in the Horn River basin — the area around Northern Rockies Regional Municipality.
But the Montney basin area has seen more development. By August 2014, close to 90 per cent of fracking operations occurred in the Montney area, the OGC report stated.
“We want to understand where the events are occurring,” said Herald.
Questions sent to the OGC about whether or not they expected these events to increase either in strength or numbers were not returned as of press time.
Report recommendations supported by CAPP
The report also made some recommendations about seismic events caused by fracking.
Three included identifying pre-existing faults, a dense array deploment requested in certain areas where more information is needed, fault zone avoidance for fracking operations, and early flow back of fluids used in fracking.
Herald said that his group was supportive of the recommendations. [Red emphasis added]
We have detailed an example of relatively large magnitude seismicity begin associated with hydraulic fracture operations. For the example discussed, we hypothesize that the large events observed are activating larger, fault-scale features beneath the treatment formation that are optimally oriented to slip in the stress field in which the events are occurring. The recorded waveform peak values are in accord with the reports of these events being felt on surface.
The recognition that events generated during hydraulic fractures can have the potential to be felt on surface is important for a number of reasons. From a perspective of due diligence, such events need to be as accurately characterized in terms of location and source parameters as possible (including magnitudes, but also source radii).
The public concern about connections from the treatment zone to groundwater aquifers can be answered with these data. From the perspective of fault activation, often this is an undesirable consequence of hydraulic stimulation if these faults provide pathways for fluid to escape formation.
Again, being able to position these faults with respect to the reservoir stimulation is of prime concern. Finally, if these events are generating ground motions large enough to be felt on surface, there needs to be an assessment of seismic hazard on site to answer questions about where shaking may be most intense and to what standards equipment needs to be built to withstand such motion. [Emphasis added]
FUNNY! Fracking Lawsuit Looks a Tad Weaker Now that We’re Having Earthquakes Every 45 Minutes by Jim Schutze, January 8, 2015, Dallas Observer
Forget about the end times. The real issue is whether 11 earthquakes in 27 hours is enough to poison the jury pool.
Remember? In August 2013, a gas drilling company sued us for $30 million — sued our city, that is — for denying fracking permits close to churches, homes and parks. So you have to wonder: If that piece of business went to court now, how could the judge seat a jury of people in this entire area who haven’t had their teeth rattled and the shit scared out of them by this weird plague of earthquakes centered near the former Texas Stadium?
See also: One More This Morning Makes Ten
I’d love to sit in on that jury selection process. “Of those of you whose homes have been shaken by multiple earthquakes, how many of you care?”
Or, more to the point: “How many of you are confident that the scores of earthquakes have nothing whatsoever to do with damn fracking? Of those of you who are confident, how many of you can name the president of the United States?”
Granted, scientists are not quite ready to lay blame for the shaking on fracking or the underground disposal of drilling waste from all those wells just yet, and the Texas Railroad Commission gets touchy about speculation along those lines. Hey, maybe the sudden spate of quakes here since 2008 is coinky-dink. Want to bet your lawsuit on that?
The company that sued Dallas, Trinity East, had a couple toes to stand on: In 2008 our brilliant City Council voted to take a check for $19 million from them — quickly cashed and spent, of course — in exchange for 3,600 acres of mineral rights within the city. But that deal came straight out of the closed-door good-old-boy system at City Hall — same people who sponsored the Trinity toll road — where everything is under the table and nobody knows about a deal until the deal is already done.
In February 2013, we found out that former City Manager Mary Suhm had been working for Trinity East since 2008, helping them get their deal done, and we only found that out because council persons Angela Hunt and Scott Griggs managed to bust out a secret memo revealing it.
See also: “Mary Suhm Signed a Secret Side Deal.”
Suhm had promised the council she would work to make sure there was no fracking in parks. The memo showed she had agreed to help Trinity East get a deal for fracking in parks.
I never blamed Suhm as much as some people did. Her job was always to scarf up all the money she could for stuff like the toll road, just about any way she could, even if meant selling the city’s parks down the river. The real villains were the rest of the council who went along with it. May I please mention again — one of my favorite stories — that when Hunt called Suhm out on the secret side deal, council member Vonciel Jones Hill compared Hunt to Haman, the killer of the Jews in the Bible’s Book of Esther. Huh? OK, see what I mean?
The first thing City Hall did when Trinity East filed suit was take the whole matter back behind closed doors where it started. The city and the company agreed that the most important thing for both to do was handle their differences in secret and keep the prying eyes of the public out of the whole fracking question.
And you can see their point. The city and Trinity East were doing just fine together until Hunt and Hill turned the light on. But now back to my original question: What about those earthquakes? How do you keep those secret?
Presumably, one side or the other should have some leverage in the threat of taking it to court rather than settling. The courthouse and an actual trial ought to look better to one of them than the other. And in fact until the whole city started shaking like a bowl of Jell-O all the time, I might have thought it was Trinity East that would have had the edge at trial. Dallas did take their check and spend it, then denied them the right to drill.
But, c’mon. The entire Trinity East argument — the argument of the entire fracking industry, in fact — is that fracking is safe and harmless as kittens with a ball of string. So I ask again: eleven earthquakes in 27 hours?
Eleven earthquakes in 27 hours? Eleven earthquakes in 27 hours?
The jurors are going to look at those Trinity East dudes and see horns and tails on them. Talk about Haman. I’m not saying the city should hope or try to go to court. Always better to settle if you can. But they absolutely should not offer more than five dollars and a kick in the ass. [Emphasis added]
Dallas Earthquake Causes Water Main Break by Bradford Pearson, January 6, 2015, Dallas Front Burner
So these earthquakes have now gone from “Oh, those are kinda cute and fun and not at all harmless” to “these are actually gonna cost us some money.” This is from before tonight’s quake, but after this afternoon’s. And it’s crazy that I even have to differentiate.
Thor Johnson: Another video of the earthquake damage one block from my house
Click on image to go to article to view video
ALSO FUNNY! BREAKING: Texas Railroad Commission to start naming DFW earthquakes by TXSHARON, January 7, 2014, Bluedaze
[Refer also to:
Slide from Ernst presentations