This is a post you will want to refer to in the future.
If you haven’t heard about fracking, then you’ve been hibernating. As a reader of this blog you are probably suspicious of the hysteria surrounding this old completions process. And you should be. I’ll give you the facts so that you can argue the issue effectively.
To begin, we’ll go over conventional drilling. This involves drilling a vertical hole in the ground and setting a pipe in the bore. Next comes compeletions, such as perfing. You have this pipe in the ground and you want to open up say 20 feet of it to let the oil flow out of the sandstone into your bore. To do this you lower a special explosive charge, which consists of small shaped charges on a tool called a gun. This is set off and blows perfectly round holes in the pipe we call perforations. The oil then flows into the pipe and up to the surface. Later as the well ages you come back and set a pump to pump the oil out. This is conventional production.
Now occasionally in the old days they would come across a formation that had oil in it, but it didn’t flow particularly well (pun intended). This is called tight oil. Way back when, they’d put dynamite down the hole and set it off. Amazingly this would actually work to stimulate the formation, though results were not always consistent. This was the original fraturing technology, or frack job.
Around 1947 engineers invented hydraulic fracturing which used water and sand to fracture the formation with high pressure, with the sand holding open the fractures. This technology was developed over the years and was quite common by the early 1970’s. I’ve read papers from that time period discussing the technique. Hydraulic fracturing is therefore old technology that has been around for a long time; in fact, over 4 million oil wells have been hydraulically fractured. In 1997 I even bought a used frac tank (used to store the water) for a small plant I was running.
Now there was a type of formation that no one could produce, the famous shale formations. They had a lot of oil in them, however drilling a vertical well and fracking it gave poor results since you could only get say 50 feet into the formation from your bore, so the oil you could eventually produce was limited to an uneconomical amount. You would have basically a cylinder 80 feet high and 50 feet in radius. There’s just not enough oil contained in that cylinder to make you any money.
In the mid aughts horizontal drilling was more-or-less perfected and someone came up with the bright idea to run the bore horizontally in the shale. Now your cylinder just became up to 2 miles long, and thus the potential was there to produce a lot of oil (and gas). A shale oil horizontal well can typically be counted on to deliver over 300,000 bbls. of oil today. That is economical to produce.
There was one big problem. You could only frack say 50 feet of it. If you tried to do more, all you would end up doing is pumping your water into the formation through the first section of your frack. In other words, you could frack say 50 feet, and then the process would stop as you could not maintain pressure.
Here then came the new technology. It was called multi-zonal fracking which basically consists of using sliding sleeves to cover up previous frack zones and move to a new zone. This allowed oil companies to place fracks down the entire 2 miles in different zones. THIS was the new technology, not hydraulic fracturing.
So how did this mass confusion arise? It started innocently enough with a newspaper article describing the shale boom. The reporter wanted to insert some slickster jargon (and the oil patch has plenty of jargon), so the reporter called the new technology “fracking”, instead of giving a detailed description of the sliding sleeve technology which had been the breakthrough. I do not believe the reporter was malicious, I believe instead she wanted to use the sexy term “fracking” to spice up the story.
Only a few weeks later the eco freaks came crawling out whining how oil companies were experimenting on our water supply with this new technology. As an aside, I wonder what they would think about acid stimulation (LOL).
So let’s analyze the scare stories. You know, fracturing will pollute the water. I guess they think you will get huge fissures coming up and polluting the water table. To get an idea of how stupid this is, first take your two hands and touch your thumbs and pointer fingers together and make a circle. This is about the size of the bore hole. Now imagine standing at the base of the Empire State Building and looking up the side of the building. The top of the building is way up there, in fact you can’t even see it. Except that’s not high enough. Stack 10 Empire State Buildings on top of each other, and now you have the right height. Yes, the small circle of your hand (the horizontal well bore) is separated from the water table by 10 Empire State Buildings of rock and clay.
How about the fissures? Well unfortunately for the eco freaks, in order to scare you they always make sure to mention the recipe for frack fluid. Read any news article about fracking and you will be sure to see the following: “sand, water and CHEMICALS”. They really want to mention the chemicals, which as an aside are similar to your hair conditioner, but that doesn’t matter, it could be tetra methyl death and still would not matter. Did you notice “sand”? Oops, they’ve screwed up. Why is there sand in the frack fluid? Yes, that is right, the size of the fractures are the width of a grain of sand and the sand props the fractures open after the pressure is taken off. Oops. Furthermore an oil company is lucky if they can get these sand sized fractures to extend even 100 ft. from the well bore. That leaves a good 10,000 feet of rock and clay before you get to the water table.
Finally you have the scare stories of lighting water on fire. Personally I think this is naturally occuring methane. In fact, that is how you find oil and gas. You look for surface indications like methane bubbling up or oil seeps like the La Brea tar pits in California. You don’t have to believe me on this, just Google search “methane separator water well” and you will find these tank devices for sale. They separate out the methane from well water and vent it off through a pipe to your roof. Methane in well water has been around.
But there IS a small chance that an oil company is responsible, though this was never claimed and there was never a lawsuit. The problem here is that people now confuse “fracking” with drilling and production. IF there was a problem, 99% of the time this was due to a fly-by-night company doing a crappy job with a cement job. Think about the Macondo Oil Well blow out that took down the Deep Water Horizon. That is an example of a crappy oil company screwing up a cement job. Bottom line, this has absolutely nothing to do with fracking and instead involves the conventional drilling and completions process. In that case (pun intended) gas can leak up the outside of the well casing and into the water table. Again, this has nothing whatsoever to do with fracking and is a potential problem with any oil or gas well.
The final myth is the earthquake myth. Fracking does not cause earthquakes. What probably causes earthquakes is the disposal of produced water. Most people think of oil wells as tapping into an underground lake of oil. This is incorrect. What you do is drill into sandstone, shale, or other rock formations and release the trapped fluid. The fluid is a mixture of oil, gas, and salt water. The fluid is called emulsion. At the surface you separate out the emulsion into its constituents in a process vessel called a treater, and you get your oil, gas, and salt water. Unfortunately the salt water is saltier than the ocean in most cases and there is no way to clean it up since you would end up with tons and tons of contaminated salt. Instead what happens is that companies drill disposal wells and pump the water back into the formation, or into a depleted formation.
This is the problem. In Oklahoma many of the older wells are what we call “watered out”. There might be 100 bbls. of water for 1 bbl. of oil. When oil was high, companies discovered that they could pump real hard on a few wells, out of the water layer, and this would allow them to produce oil economically from the other wells. This of course produced a lot of salt water, so disposal wells were drilled to handle it. Unfortunately the wells were drilled on hidden fault lines. This caused the earthquakes, not fracking.
Now yes even shale wells will produce a lot of salt water, a typical number being 30 bbls. of salt water for 100 bbls. of oil. This is known as the water cut. This water has to be disposed of (as is the case for the vast majority of oil wells). This is not a problem if you make sure there are no faults where you are drilling. In the Bakken they probably dispose of 300,000 bbls. of salt water per day, and they don’t have earthquakes. Same in Saudi Arabia where they produce probably 10 times as much water.
This ends my review of the fracking controversy. It is stupid, and hopefully you are now better equipped to argue it.