Fluid Injection and Seismic Activity in the Northern Montney Play, British Columbia, Canada, with Special Reference to the 17 August 2015 Mw 4.6 Induced Earthquake by Alireza Babaie Mahania, Ryan Schultzb, Honn Kaoc, Dan Walkerd, Jeff Johnsond, and Carlos Salasa, April 2017, Published online before print February 2017, doi: 10.1785/0120160175, Bulletin of the Seismological Society of America
b. Alberta Geological Survey, Alberta Energy Regulator, Suite, 205, 4999‐98 Avenue, Edmonton, Alberta, Canada T6B 2X3
c. Pacific Geoscience Center, Geological Survey of Canada, 9860 West Saanich Road, Sidney, British Columbia, Canada V8L 4B2
d. British Columbia Oil & Gas Commission, No. 300, 398 Harbour Road, Victoria, British Columbia, Canada V9A 3S1
In this article, we analyzed the recent seismic activity in the northern Montney Play of British Columbia in 2015 and its connection with fluid injection (hydraulic fracturing and long‐term injection of gas and wastewater disposal) in the region. The earthquake sequence used in this study includes 676 events from 3 October 2014 to 31 December 2015 from the Progress Energy earthquake catalog with moment magnitude as small as 1. Spatial and temporal correlation of seismic activity with the fluid injection in the region revealed that these events are better correlated with hydraulic fracturing (correlation coefficient of ∼0.17 at confidence level close to 99.7%, with a lag time between 0 and 2 days) than other types of injection. Using the double‐difference relocation technique, we obtained depth constraints for some of the events for which supplementary, industry‐provided waveforms were available. The depths of these events range from 0.5 to 2.5 km and are mostly constrained above the target zone where hydraulic fracturing was taking place. The best‐fit moment tensor solution for the event on 17 August 2015 gives a moment magnitude of 4.6 and a predominantly thrust mechanism in the northwest–southeast direction with a shallow focal depth of 4 km. This is consistent with that obtained through double‐difference relocation for this event (1.3 km), given the depth uncertainty of the moment tensor inversion.
Federal scientist has proof: fracking by Petronas-owned company caused a big B.C. earthquake by Erin Ellis, April 12th 2017, National Observer
The largest earthquake yet detected in British Columbia’s northeastern shale gas region was conclusively caused by fracking from Progress Energy Inc. in August 2015, says a federal scientist whose study was published this month.
Honn Kao, a research scientist with the Geological Survey of Canada, says it’s now clear that the 4.6 magnitude quake, which was felt at the surface near the resource town of Fort St. John, was the direct result of liquids being pumped into underground rock formations under high pressure to extract natural gas.
“It confirms what we’ve learned so far, that the majority of earthquakes induced in northeastern British Columbia appear to be related to hydraulic fracturing operations rather than other injection operations,” Kao said in a telephone interview from his office in Sidney, B.C., near Victoria.
Progress Energy of Calgary is owned by Petronas, the national oil company of Malaysia which has floated plans to build a liquified natural gas processing plant on B.C.’s coast near Prince Rupert. The source of the gas would be the Montney shale gas area where hundreds of small seismic events have been detected by monitoring stations since fracking began in the area in the mid-1980s. The company hasn’t made a final decision on whether to proceed with the project to ship liquified gas to Asian markets.
Support for proposals to build LNG facilities have been a key component of the federal and provincial governments’ economic policies and the issue could land in the middle of B.C.’s May 9 election.
Question of damage
“Now almost everybody, including industry and the research community, agrees that there is no doubt that hydraulic fracturing and waste water injection can cause earthquakes,” Kao said.
“Now the question is how big or how damaging these earthquakes can be.”
“This is something that’s very different from the reports for the Central and Eastern United States where they indicate that most of their induced earthquakes are related to waste water injection.”
The BC Oil and Gas Commission also reported in December 2015 that fracking was behind the quake which caused no damage. The commission is a provincial Crown corporation which regulates shale oil production.
Kao said his research, published in the Bulletin of the Seismological Society of America, was possible because Progress Energy and Canadian Natural Resources Limited shared data from their seismographic stations with him. Corporate monitoring points far outnumber those of the government.
“Progress Energy has been very open and they make it very clear that they want to know the cause of induced seismicity as much as we do,” said Kao. “They spent a lot of money setting up seismic arrays trying to figure out where are the earthquakes, how big they are and so on.”
More monitors installed
The key issue now is whether seismic activity can be consistently kept below magnitude 4 which cannot be felt at the surface, he added. [What’s the purpose of this belittling? Quakes below M4 are felt at the surface and some cause damage.]
Phil Rygg, director of communications for the BC Oil and Gas Commission, says the study mirrors its research on the Horn River Basin near the Yukon border and the Montney region where the 4.6-magnitude earthquake occurred.
That’s why the commission has required more monitoring stations, prompt reporting of ground motion and a halt in production after a quake of magnitude 4 or higher. Progress Energy did stop work immediately after the Aug. 17, 2015, earthquake, but resumed after a go-ahead from the commission.
Rygg noted there has been no surface damage from induced quakes in British Columbia. [But subsurface damage has occurred. Is anyone monitoring industry’s rogue methane migration into groundwater and buildings caused by the quakes and well bore damages from the quakes? Most likely not.]
David Sterna, director of communications at Calgary-based Progress Energy, declined to be interviewed because he said the company hasn’t yet reviewed the latest research. But he said in an emailed response that there have not been any stronger earthquakes since 2015 and the company has installed more detection equipment since then.
“Since 2012, Progress Energy has completed more than 3,400 hydraulic fractures without any incident of injury or property damage,” Sterna wrote. “As part of our commitment to safety, Progress Energy has installed 17 localized seismograph arrays in our operating areas to monitor potential occurrences of induced seismicity from our activities.” [Emphasis added]
Anticipating hazards from fracking-induced earthquakes in Canada and US
by Seismological Society of America, April 12, 2017, phys.org
As hydraulic fracturing operations expand in Canada and in some parts of the United States, researchers at the 2017 Seismological Society of America’s (SSA) Annual Meeting are taking a closer look at ways to minimize hazards from the earthquakes triggered by those operations.
… At the SSA Annual Meeting, experts will speak about the growing recognition that hydraulic fracturing or fracking can produce earthquakes magnitude 3 and larger, acknowledging that this type of seismic activity is difficult to predict and may be difficult to stop once it begins.
Most induced earthquakes in Canada have been linked to hydraulic fracturing, in contrast to induced earthquakes studied in the central and eastern United States. In the U.S., these earthquakes have been linked primarily to massive amounts of wastewater injected back into the ground after oil and gas recovery. However, some presentations at the SSA meeting will take a closer look at the possibilities for fracking earthquakes in the United States.
Michael Brudzinski of Miami University and his colleagues will discuss their work to identify swarms of small magnitude earthquakes in Ohio that appear to be correlated in time and space with hydraulic fracturing or wastewater disposal. Their work suggest that there are roughly three times more earthquake sequences of magnitude 2 or larger induced by hydraulic fracturing compared to wastewater disposal in the area—even though there are about 10 times more hydraulic fracturing wells than wastewater disposal wells. Their technique, they say, provides evidence of induced seismicity from hydraulic fracturing in Oklahoma, Arkansas, Pennsylvania, West Virginia and Texas as well.
Zenming Wang and colleagues are preparing for the onset of oil and gas exploration in the Rome Trough of eastern Kentucky, conducting a study of the natural background seismicity in the area to be able to better identify induced earthquakes if they occur. In their SSA presentation, they will also discuss how an area like eastern Kentucky might assess and prepare for ground shaking hazards from induced earthquakes, since the ruptures may occur on unmapped or “quiet” faults.
In western Alberta and eastern British Columbia in Canada, a significant increase in the rate of felt earthquakes from hydraulic fracturing has researchers looking at ways to mitigate potential damage to infrastructure in the region. In her SSA presentation, Gail Atkinson of Western University will discuss the factors that affect the likelihood of damaging ground motion from fracking-induced earthquakes.
Based on these factors, Atkinson proposes targeted “exclusion zones” with a radius of about five kilometers around critical infrastructure such as major dams. This would be combined real-time monitoring to track the rate of seismic events of magnitude 2 or greater within 25 kilometers, [IS THAT ENOUGH?REFER BELOW FOR HOW FAR THE 4.6M QUAKE WAS FELT IN NE BC] with fracking operations adjusted to potentially reduce this rate to less hazardous levels. [Emphasis added]
More information: “Correlation Algorithms to Better Characterize Seismicity Induced by Hydraulic Fracturing” will be presented at the SSA Annual Meeting on Wednesday, April 19. All presentation abstracts for the 2017 SSA Annual Meeting can be accessed at meetings.seismosoc.org/abstracts
[Refer also to:
But the BC Oil and Gas Commission would not grant the Tyee an interview with Walker to discuss his presentation in detail.
Walker gave another presentation on lessons learned from the industry-triggered earthquakes in B.C. at a 2015 Montreal meeting of the American Geophysical Union.
At that meeting, he said that controlling earthquakes caused by wastewater disposal wells was easier than managing tremors set off from fluid injection from hydraulic fracturing. [Emphasis added]
Search “frac quake” on the ernst versus encana website for many more reports, papers and posts on frac quakes, the risks and massive damages on the surface that they can cause. ]