Fracking is making headlines.
But do you know what it is? And how it affects the environment? And you?
“Fracking” is a slang term for a process called induced hydraulic fracturing.
This process creates veins or seams (“fractures”) in rock to enable removal of hydrocarbons like natural gas and oil. Fracking is typically done in non-porous or impermeable layers of rock and rock formations because the hydrocarbons are otherwise trapped in the rock. Creating fractures in the rock opens up channels for the hydrocarbons to escape.
PICTURE THIS: Imagine draining food in a colander. The colander is similar to a porous formation. Water drains freely through the colander, and any remaining water can be shaken out with a little extra effort. Now imagine that same colander lined with two layers of coffee filters. This would represent impermeable rock. There is very little drainage, and shaking yields limited results. In this case, you need to poke holes in the coffee filters (like fractures) to help the water flow.
Fracking in Shale
Shales are some of the largest rock formations that contain natural gas and oil. These formations are deep in the earth and found in abundance all over the world. Fracking is typically done in shale formations, and has received a lot of publicity as the fracking industry expands.
Shale formations are under tremendous pressure, which can cause the fracking seam to seal quickly due to scaling, debris and clumping from the mixed hydrocarbons. To combat this, a fracking fluid containing proppants (sand) is injected into the seams and acts as mini-spacers to stop the new seams from closing. Proppants are a solid material like treated sand or man-made ceramics that contain scale inhibitors and friction reducers to help keep the seams clear.
Before fracking in shale, a few things must be done.
- First, the main wellbore is drilled and cemented into place.
- Next, the horizontal arms from the main vertical bore are drilled — Occasionally, specialized equipment and minor explosive charges are used following this step, though fracking fluid injection lines typically are run into the horizontal well arms. This fluid (90% water, 9.5% proppant, and 0.5% chemicals added) is highly pressurized up to 15,000 psi at about 100 barrels per minute.
Fracking and the Environment
Concerns have been voiced around the seismic and environmental impact of fracking, and with good reasons, due to some accidents and poor practices in the industry.
Many fracking companies have a high degree of environmental responsibility and go beyond required industry standards to ensure they limit the environmental impact of their activities. These companies use considerably less water than permitted by standard fracking guidelines. They filter used water and bring it up to tight standards before responsibly disposing of it.
However, damage from unstable seismic activity can be as detrimental to fracking companies as it can be to the local community. Seismic activities can destroy wells and piping, resulting in millions of dollars in fines to the fracking companies because of the potential of leaking and environmental damages. Several environmental studies have concluded that fracking activity has no statistical relationship to seismic changes in areas already susceptible to seismic activity.
Every day, more and more gas reserves are discovered, and the current reserves are often determined to be larger than previously thought. Current estimates indicate we could power the world’s energy demands for 100 years at the current growth projections using only natural gas as the fuel. While these estimates have been debated, the point is clear that this natural power source is available in abundance.
Current technology advances have made this an economical energy source to harvest.
Now that you have an idea of what Induced Hydraulic Fracturing is, explore the Current Technologies and Equipment used to get the “good stuff” out today. When you’re finished, review how advancements in technology are addressing the 4 major concerns associated with fracking by Making the Process Safer. And don’t forget to follow up on your research! Check back or subscribe for a reminder — we’ll be wrapping up our Fracking Series soon by answering Why We Frack (in the First Place).