Some Truths about Fracking (and Earthquakes), Part 3

WHATS IN THIS BLOG:
• Four-year old boy illustrates how oil molecule travels through shale rock.
• Oklahoma in 2015 recorded six times as many earthquakes as California.
• Most of these earthquakes are a result of oil and gas activities.
• Is fracking causing the earthquakes?

Earlier articles on Some truths about Fracking, Part 1 and Part 2, are available (click on the links, then minimize to return to this blog article).

PRESENTATION ON FRACKING AND EARTHQUAKES:
On March 2 in the small town of Independence, Kansas, not far from the Oklahoma border, I gave a presentation to almost 50 attendees: teachers, corn and cattle farmers, lawyers, retired persons, as well as geologists and petroleum engineers.

THE ENTERTAINING PRESENTATION RELIED HEAVILY ON PROPS:
(1) Ryker, aged 4, pretended he was an oil molecule and showed he had difficulty getting past people pretending to be lumps of shale rock in order to reach the wellbore. However, his progress was much faster when he got into a fracture (crack) between two lines of shale-lump-people. Learning: you have to crack up the shale to get the oil or gas out fast enough to make a profitable well. To watch a 2-min clip of the little guy, click on this link . After the video, turn it off and click on the header (at the top) labeled Ian Palmer — Gray Nomad.

(2) Volunteers stood in a line to represent geological layers of rock, at different depths, in Oklahoma:
a. Eyes stand for aquifers (shallow depths less than 1,000 feet usually)
b. Shins stand for shale (Woodford shale which exists over a large part of Oklahoma and surrounds Oklahoma City, and contains lots of oil and gas. Typically about 5,000 feet deep)
c. Ankles stand for Arbuckle limestone (where most disposal wells inject their wastewater)
d. Boots stand for Basement (thick granite where large faults exist)

(3) Using broom handles to represent wells and paper cutouts to represent fractures, I explained how the new technology has made shale-gas and shale-oil a revolution. The key is a long horizontal well (1-2 miles) which is fracked about 20 times along its length by pumping water down the well under high pressure. Total water pumped is typically 5 million gallons (yes that’s 5 million jugs of milk), which would cover a football stadium to a depth of about 10 feet. In shale rock, which is heterogeneous, the fracs are a complicated system of cracks, which enables oil or gas molecules to enter a crack then zip along the cracks until they reach a well.

EARTHQUAKES FROM THE FRACKING OPERATION:
(4) The fracking operation splits the shale rock in hundreds of different places, each like an axe splits a log of wood. During each split, some of the energy is released as an earthquake but the energy is so small it’s called a micro-earthquake. So there are hundreds of micro-earthquakes created in each frac job. These can’t be felt at the surface……each has only as much energy as a 1-gallon jug of milk falling from a kitchen countertop to the floor.
(5) Some of the frac water comes back out when a well is turned on to production after the fracking operations are complete – but only about 20% of it. The rest is sucked into the shale and trapped.

So a shale-gas or shale-oil well will produce gas or oil, or sometimes both, plus some of the frac water, plus salt water which was originally in the shale. The oil or gas is sent to a pipeline, while the wastewater must be disposed of. This wastewater volume from a single well is probably a football stadium filled to 10 feet for each well (or maybe more than 10 feet).
(6) Disposal wells are often drilled into the Arbuckle limestone (the ankles). The volume of wastewater has increased steadily from the year 2000 to 2010, because of the increase in production wells drilled during this time (because the price of oil went up toward $100/barrel). To illustrate the volume of wastewater injected into a disposal well:

a. For 2000 I used a small bucket and a small funnel to inject wastewater from 1 production well (1 football stadium to a depth of 10 feet).
b. For 2005 I used a medium-sized bucket and funnel to inject wastewater from 10 production wells (10 football stadiums).
c. For 2010 I used a large bucket and large funnel to inject wastewater from 100 production wells (100 football stadiums).

EARTHQUAKES FROM DISPOSAL WELLS:
(7) The high-pressure wastewater plume is like a balloon that spreads out from the bottom of the disposal well. In 2010 the plume spread out a lot more than in 2005. It can spread out by 10 miles or more – like from Independence to Neodesha or to Cherryvale or to Caney.

(8) If the high-pressure wastewater plume hits a fault in the Basement, or the top of a basement fault in the Arbuckle, it may force the fault to slip along its length, and this creates an earthquake. A fault is just a big fracture. A big fault means a big earthquake. The wastewater plume may takes months or even years to reach a big fault.

(9) These are real earthquakes, which are felt at the surface of the earth:
a. See chart for damage caused by different magnitudes of earthquakes.
b. An M = 3 earthquake is same as 27,000 jugs of milk falling to the floor (c.f. a micro-earthquake created by a fracking operation is 1 jug of milk).
c. An M = 5.1 quake (24 million jugs of milk) was recorded in Fairview, northwest of Oklahoma City, on 13 February 2016 (third-largest quake ever recorded in Oklahoma).

TAKEAWAYS:
• Fracking does cause earthquakes, but these are micro-earthquakes with M < 0, and are NOT felt at the surface and are NOT damaging.
• High-pressure wastewater injected into disposal wells spreads out in a plume. If/when the plume hits a fault, the high-pressure wastewater can cause the fault to slip and cause an earthquake of magnitude M = 3 or greater.
• Oklahoma in 2015 had 6 times as many earthquakes as California.
• The largest earthquake in Oklahoma occurred in Prague, Oklahoma, on November 2011. It was magnitude 5.6 in, and it cracked walls and toppled chimneys.

• For earthquakes induced by disposal wells, what can be done? New disposal wells need to consider whether there are faults nearby. High-volume and high-rate disposal wells need to be monitored for earthquakes. Volumes of wastewater can be reduced, in current disposal wells, or they can be shut down. Alternatives to injecting into the Arbuckle formation can be found, which are further from the Basement.
• What is the likelihood of “the big one” occurring? Apparently, swarms of earthquakes sometimes precede a big one. Oklahoma has been getting swarms of quakes in 2014, 2015, and 2016 (see bar-chart picture).
• I am writing a new book about fracking and earthquakes, called Fracman: the Risks and Perils of Fracking Decisions. The first draft is almost complete.
• I am available to present this one-hour presentation. Please contact me at my email ian@higgs-palmer.com

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The Gray Nomad
Probing the practice of Christian believers……

For nation will rise against nation, and kingdom against kingdom, and there will be famines and earthquakes in various places. [Book of Matthew, chapter 24].