Non-Intuitive Result

This quote was in response to a query from Adrian Demaid (Open University, UK), who asked me for examples where research had an unexpected result.

“About twenty-five years ago Battelle was asked to estimate the cost of fracture to the US economy, we came up with an amount of about a few percent of gross domestic product.  While the actual figure can easily be disputed, the real cost is probably very large.

The key to arriving at our result was an appreciation of the role that material variability plays in engineering specifications. It appears that typical engineering standards assign properties about two standard deviations below the mean of alloys when specifying dimensions. For example, if the coefficient of variation of the yield strength of a particular steel is seven percent, it is assumed that all pieces of that steel are treated as if their yield strength is 14 percent below the actual mean. Of course, engineers did not work this position out statistically -— the various rules-of-thumb just seem to come out that way. If metallurgists could reduce scatter consistently, we would have lighter structures with no sacrifice of safety. Extending this idea to other mechanical properties and plugging our estimates into the economics model gave rise to the large costs that we reported.

The above argument leads to the non-intuitive conclusion that the fracture research with the greatest economic benefit would be in the area of materials production (especially welding). Our report soft-pedaled this point, since the sponsors had a vested interest in justifying additional funding for fracture mechanics research.

When I made my point about the importance of production research, at technical meetings, I was attacked by researchers with the same motivation  — they cited all sorts of unsolved analytical problems and promising experimental approaches. My reply that success in their approaches would at best lead to a tiny reduction in safety factors only poured oil on the fire.”

Fracking Can Cause Earthquakes (Rev. 7 Jan 2012)

Scientists have coined the term 'induced seismicity' to describe earthquakes caused by human activity. Several examples of earthquakes in the past caused by oil and gas drilling have been documented. These earthquakes can be triggered when water under pressure encounters a fault (i.e., a crack in the subsurface rock, which can be very small or up to miles in extent)*

The fracking process produces tiny earthquakes as a side effect of the cracking to release the gas. and oil trapped in the rock. But they are detectable only by sensitive instruments. The question is whether the current technology being used in Ohio can trigger earthquakes large enough to be felt by humans. In order to avoid the possibility of earthquakes, the driller has to be sure that his shaft does not encounter a fault. Unfortunately, the the number, size, and location of all faults in Ohio is unknown.

In the first half of 2011, people living in both England and Oklahoma felt tremors. In both places expert analysis has suggested that they were caused by fracking. The second half of 2011 has seen major earthquakes centered in both Virginia and Oklahoma. Activists have claimed that these bigger earthquakes are also caused by fracking, but a good case has not yet been made.

There is also evidence of earthquakes at, or near, fracking-waste-water injection well sites (storage pits). Good evidence for such earthquakes was found near injection wells in Arkansas; there were multiple small earthquakes, whose numbers and intensity greatly diminished when injecting liquid into the wells was stopped. Other suspect earthquakes have recently occurred in Texas and West Virginia, as well as in Ohio (Youngstown and Marietta).

It is not only fracking waste that can cause earthquakes – any liquid will do. In an on-line comment on a 31 December, 2011 article in the Columbus Dispatch, Jeff Cox wrote:

“The increase of fluid pressure from the injection of liquids wastes in northeast Ohio and near Lake Erie by the Stauffer Chemical Company into a nearly 6,000 feet deep sandstone formation was implicated by Ohio University researchers to have triggered a 5.0 magnitude earthquake and two aftershocks on January 31, 1986 … Two and possibly three prior earthquakes in that area during 1983 are thought by researchers to have likely also been caused by the same deep well injection site. ... The Ohio Geological Survey and other geologists determined that a sequence of earthquakes of magnitudes ranging from 2.6 to 4.3 that shook downtown Ashtabula, Ohio from 1987 to 2003 were caused by a nearby deep well site injecting hazardous waste fluids near two faults into a 5,900 feet deep basal sandstone formation. The researchers state, “like many faults that rupture in … stable subcontinental region earthquakes, the faults were previously unknown…”

Youngstown suffered eleven earthquakes in 2011. After the magnitude 4.0 quake on New Year's Eve, the State finally stepped in and ordered a five-mile exclusion zone around the guilty injection well and verified that a previously unknown fault the cause. Subsequently the owner of the well agreed to empty it.

Some have argued that there are very many injection wells that do not cause earthquakes. This is true. It is only the unlucky driller who encounters a fault and triggers an earthquake. At a minimum, Ohio should forbid deep drilling at locations near critical infrastructure (bridges, dams, pipelines, etc.) and in areas of high population density.

The West Virginia State Geologist, faced with a Youngstown-type situation, has called for a mapping of faults. This is good advice for Ohio, since we don't know where all of the faults in the State are located.

ADDED COMMENTS

9 Jan 2012:Article in Columbus Dispatch: State to buy seismomiter (sp ?)

10 Jan, 2012: Letter to the Columbus Dispatch from API executive "The overwhelming majority of hydraulic-fracturing operations take place without any reported seismic activity"   meaning that they concede that fracking can cause earthquakes.

11 Jan 2012: CAVEATS: 


1. Solving the earthquake problem does not mean that I am giving deep drilling a green light. The very serious pollution-generation and explosion-potential problems remain.


2. By far the greatest sources of energy waste and greenhouse-gas generation are electric power plants and motor vehicles. The technology exists to replace coal and gasoline with natural gas. The industry has an obligation to produce the gas with the greatest regard to publichealth and safety.

14 Jan 2012: Found reports of induction-well-caused earthquakes in local papers from NY  ("Fracking Sparks Eartquake Concerns ", democratandchronicle.com, 16 N ov. 2011) & SC

15 Jan 2012: Report found from Reuters that sensing out faults will cost $5 million per well. But I believe that the Governemnt is doing a nation-wide survey which is due in Ohio in two years.

FURTHER READING

* All references are on-line and available by Googling the title, except that of Jeff Cox, which is reproduced in full in the text.

Fracking and Earthquakes

Anon “Can Fracking Cause Earthquakes?” The Week 14 November 2011

Corbyn, Zoe “Model Predicts Size of Fracking Earthquakes” Nature 09 Dec. 2011

Daley, John C. K. “US Government Confirms Link Between Earthquakes and Hydraulic Fracturing” Energy Daily, 15 Nov. 2011

Lawrence Berkeley Laboratory (LBL) “What is Induced Seismicity ?” (undated report on LBL web site; heavy going, but worth it)

Ohio Geology

Michael C. Hansen “Earthquakes and Risk in Ohio” Geofacts No. 3, ODNR, April 2007

Spencer Hunt “Tracking Tremors” Columbus Dispatch, 15 Nov. 2011

ODNR Division of Geological Survey – Ohio Seismic Network “Ohio Earthquakes of 2.0 or Greater Magnitude. 2010 to the Present” (web site)

Earthquakes Attributed to Fracking

Austin Holland “Examination of Possibly Induced Seismicity from Hydraulic Fracturing in the Eola Field, Garvin County, Oklahoma” Oklahoma Geological Survey Open-File Report OF1-2011, August 2011 (Magnitude 2.8, 18 Jab 2011)

Brian Swint “Fracking probably caused small Blackpool earthquakes in U.K.: Report” Bloomberg News, 2 November, 2011 (Magnitude 2.3, 1 April 2011 and Magnitude 1.5, 27 May 2011)

Earthquakes Attributed to Injection Wells

Arkansas, 2010-11 (Highly Probable)

Arkansas Geological Survey “Earthquakes” (web site with catalog of earthquakes up to date)

Sarah Eddington “Arkansas Earthquakes Decline After Injection Well Closes” Insurance Journal, 16 Mar 2011

UPI.com “Clues Sought in Arkansas Earthquake Swarm”

Northeast Ohio, 1986-2003 (Probable)

Jeff Cox "Comment" Columbus Dispatch (on-line version, found just below Sanner article cited below)

Jeff Hecht “ Waste burial blamed for earthquakes” New Scientist, 1 Sep 1988

C. Nicholson, et al. “the northeastern Ohio earthquake of 31 january 1986: Was induced?” Bulletin of the Seismological Society of America, Feb 1988, page 188

Leonardo Seeber, et al. “A Fluid-Injection-Triggered Earthquake Sequence in Ashtabula , Ohio: Implication for Seismogenesis in Stable Continental Regions” Bulletin of the Seismological Society of America, Feb 2004, page 76

Marietta Ohio, 2011 (Probable)

Anon. “Quake shakes region again” Parkersburg News and Sentinel 1 Sep 2011

Younstown OH, 2011 (Highly Probable)

Karl Henkel “Is new well source of quakes ?”, Youngstown Vindicator, 5 Nov 2011

Spencer Hunt “State plans to relieve pressure in brine well to quell quakes” Columbus Dispatch, 5 Jan 2012

Ann Sanner (AP) “Disposal of brine into well halted” Columbus Dispatch, 31 Dec 2011

Thomas J. Sherran (AP) “Brine well caused quakes, expert says” Columbus Dispatch, 3 Jan 2012

Joe Vardon “State links quakes to work on wells” Columbus Dispatch, 1 Jan 2012

Dallas-Fort Worth Airport TX, 2008-9 (Probable)

Cliff Froelich, et al. “The Dallas-Fort Worth Earthquake Sequence: October 2008 through May 2009” Bulletin of the Seismological Society of America, Feb 2011, page 76

West Virginia, 2010 (Highly Probable)

Pam Kasey “Geologist: Site Injection Wells away from critical infrastructure” The State Journal 5 Jan 2012


DEP Officials See Possible Link between Fracking Disposal, Earthquakes", dailymail.com, 12 Jan 2012

Recent Large Earthquakes (Probably Unconnected to Fracking)

USGS Earthquakes Hazards Program

Virginia, 23 Aug 2011, magnitude 5.8

Oklahoma, 6 Nov 2011, Magnitude 5.6