I want to go back to basics this week. I write a lot about regulations, pipelines, and treating gas after the well head. But an ongoing question and concern that I find a lot of people have, is hydraulic fracturing also known as fracking. So I want to simply discuss in this blog exactly what hydraulic fracturing is.
By simple definition, fracking is a technique used when drilling for natural gas and oil. It is a technique where rock below the surface is fractured open by pressurized liquid made up of sand, water, and chemicals. So what does that mean?
I am going to start with the processes of drilling and thus leading to the fracking segment of drilling. When you begin drilling, the well bore is lined with steel pipe and the annulus between the well bore and lining is filled with cement. There is a minimum of 7 layers of this process to ensure that the well does not collapse and the fresh water aquifers are protected from any contamination. As you can tell form the picture on the right, there are many layers between the well bore and the aquifer.
Now that we understand the initial process of the initial drilling process, let’s move on the hydraulic fracturing process. This video made by Marathon Oil does a great job of explaining and showing the drilling and fracking process.
Once the well is drilled, a perforating gun is sent down the well and an electric impulse denotes bullets which creates holes in the shale. Proppant is then sent down to open the shale and hold open the cracks in the shale.
Proppant is made up of 99% sand and water. The proppant allows the gas and fluid to escape the shale and flow up the well. The picture you see is actually proppant that has been used at a well site in the hydraulic fracturing process. The sand has been washed and dried to show what the proppant that is used looks like.
Finally, you can see from the picture below, the entire process from when the well is set and the flow of gas has begun with the fracking process. Fracking has gotten a negative light shown on it but learning the process can help see what goes on behind the scenes when it comes to drilling for oil and gas. Hydraulic fracturing has revolutionized the way we drill for gas. It has allowed us to retrieve gas from tough shales that were difficult to reach in the past. Companies take extra precautions to protect the aquifers and avoid contamination of the earth all while providing the much-needed gas resources our society needs.
