The Shale Controversy

The Shale Controversy

In the early twenty-first century, the shale-gas and shale-oil revolution took off in the United States, and Dr. Palmer was in the middle of it, beginning a new career as a consultant in oil and gas production. Dr. Palmer had worked as a fracking engineer for eighteen years at a major oil and gas company, but he gained a fresh perspective in his consultant role—the environmental view. He did extensive R&D work and taught professional classes on shale-gas and shale-oil.

The Shale Controversy assesses the pros and cons of the shale revolution in an open and transparent way, and it is written for lay readers as well as experts. Dr. Palmer strives to clarify emotional issues with facts and data, enumerating the benefits of cheap gas and oil for personal household and work use as well as the trade balance achieved for the United States. On a global scale, cheap energy has lifted millions of people into the middle class. A downside is the threat, present and future, of earthquakes induced by wastewater disposal in connection with drilling of shale wells. Although the threat has declined in Oklahoma, Texas could find the menace recurring in the mighty Permian basin.

The hot topic of global warming attributed to the burning of fossil fuels, including shale-oil and shale-gas, leads Dr. Palmer’s thoughts to the dilemma and immense challenge faced by oil and gas companies. Dr. Palmer rounds out the book with a discussion on how rapidly global warming needs to be constrained and a summary of potential solutions to meet the deadlines that the experts insist are coming at us fast.

EARLY REVIEWS

Despite having been in oil and gas for over ten years, I’ve always struggled with how to simplify the complexities of the industry. Dr. Palmer has done it in his book. It is thorough, fact rich, fair and easy to follow. If you want to explore the big questions, better understand the issues and decisions associated with powering our world, this book is a must read.” –  Mark Madison, Managing member, Absolute Oil+Gas.

“The author covers a range of engineering and science in an easily understood but authoritative manner, from the fracking of petroleum bearing shales and its contribution in the supply of oil and gas, to the dilemma of an increasing carbon dioxide concentration (from the combustion of these fuels) in the atmosphere, which results in significant global warming. He uses his experiences in his home continent of Australia, combined with his knowledge of the petroleum industry in his adopted country (USA) to illustrate the dilemma”. – Leith Cooper, Farmer and Rancher.

“Dr. Palmer has written an in-depth review of shale hydraulic fracturing in vertical and horizontal wells using historical facts detailing its humble beginning.  From drilling and completion engineers to the everyday layman, the material is presented in an easy-to-understand manner while still covering all facets of the industry- drilling, completions, water management, economics, and environment.  It is hard to put the book down before reaching the final chapters.  Anyone interested in this industry will benefit from this easy read.” – Gary Rodvelt, Global Completions Advisor at CastleRod Consulting, LLC.

Chapter 1

Aladdin’s cave from Arabian Nights was filled with tremendous treasure that the protagonists fought over, as the 2019 movie Aladdin depicted. In this book, Aladdin’s cave represents the benefits of the shale-oil and shale-gas revolution, which include a resurgent supply of cheap oil and gas in the USA, with the country becoming self-sufficient in gas and oil, even selling gas and oil overseas.

In Greek legend, Pandora’s box was filled with evils that Pandora inadvertently released when she lifted the lid. In this book, Pandora’s box represents the harm or damage that may be caused by the shale revolution, including the contamination of aquifers, induced earthquakes, and global warming.

I’m an insider reporting on oil and gas activities. I worked for corporate oil and gas companies for eighteen years, then as a consultant for twelve years—a total of thirty years. Memories of some of my activities are also recorded in the book—to add a little flavor.

To understand the shale revolution, we need to first understand fracking, the nickname for hydraulic fracturing—the technique commonly used to make oil or gas flow faster into a well. I give talks on fracking, shale-oil, and shale-gas geared toward the layperson. When I first prepared the content for my talks, I used my great-grandson, Ryker, aged four, to demonstrate why we need fracking in shale wells.

In a small Kansas town called Independence, I introduced Ryker to the audience as Molly. I bunched up twelve folks in a box shape and asked Ryker to start from one side of the box and work his way through to the opposite side. It took a couple of minutes, but after much pushing and squeezing, he made it, and his Meme rewarded him with a chocolate Easter bunny.

I told the audience that Ryker represented a gas or oil molecule able to move only slowly through a block of shale rock toward an underground well. It’s slow and tortuous because the molecule is confronted by rough and irregular pieces of shale sticking out at odd angles. In other words, the innate flowability or permeability of shale is very low.

Then we redid the demo, but this time the people were separated into two bunches, with an open pathway in between the two groups. Ryker ran along the gap and got from one end to the other in two seconds flat. I explained that when a gas or oil molecule finds itself in an open crack, it can move rapidly toward a well without the usual obstacles. And this is the secret of shale-oil and shale-gas.

When we pump a hydraulic fracture at the bottom of a well, we create cracks. Fracking is just cracking. A hydraulic fracture, or frac, is just an assemblage of cracks created in the shale. And the oil or gas molecules that happen to fall into one of these cracks can find a pathway to the well that is open and quick and easy. The more a fracking operation cracks up the shale, the more oil or gas molecules can get into the crack system and the faster they move toward the well. This means more oil or gas is produced from the well every day.

Figure 1. In a complex fracture, such as in shale rock, gas or oil molecules can move easily along crack conduits to the well.
Figure 1. In a complex fracture, such as in shale rock, gas or oil molecules can move easily along crack conduits to the well.

Now what do these cracks in the shale look like? If you walk across your driveway or along a sidewalk, you will see cracks in the concrete. They’re long and thin. That’s what cracks look like in shale underground. However, if a lot of cracks exist, some of them will join up and connect in what we call a network of cracks. This is the usual situation we see after fracking a shale layer underground, and we call it a complex fracture—see figure 1.

The second question is, How do we actually perform the operation that creates a fracture in the shale? The short answer is that we must overcome the earth stress, which is essentially the force holding the rocks together in an underground layer. The earth stress can be high enough to crush a man’s hand—as if it had been placed under a steamroller paving a roadway. We use high-powered pumps to pump water down a well, and the pressure of the water has to be thousands of pounds per square inch to overcome the earth stress in the rock. The pressure breaks a piece of the rock like an ax splitting a log, and the result is a crack—or usually many cracks. The high-pressure water cracks up the rock around a well.

Fracking is not quite as simple as it may sound at this point. Soap, sand, and chemicals are also injected along with the water. The soap is used to make the water slick, as this lowers the pumping pressure required to force the water down through the well and saves on pumping costs. The sand, called proppant, is used to prop open the created fractures after the pumps are turned off when the fracking operation is complete—see figure 2.

Shale oil gas drilling Proppant-sand holds the cracks open but allows gas or oil molecules to move freely along the cracks to the well
Figure 2: Proppant-sand holds the cracks open but allows gas or oil molecules to move freely along the cracks to the well.

The few added chemicals serve many purposes. One is a biocide to stop algae from growing in the reservoir. One is to stop the shale from swelling. Another is to stop the metal well casing from rusting. And yet another is to prevent scale from forming in the well. These are the common additives used in shale fracking.

The Barnett Shale discovery well used slickwater, but some frac operations add gel thickener, which carries the proppant-sand deeper into the fracture network and farther from the well.

Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

0 Comments
Inline Feedbacks
View all comments
0
Would love your thoughts, please comment.x
()
x