We have finally reached the final blog in our three-part series. The part I know you have all been waiting for…Shale Plays!
As you can see from the map below, the shale plays lie in the tight sand, within the basins and these geological formations are all over the United States of America. The natural resources we get from shale is considered an unconventional resource. It’s unconventional because you cannot drill into the shale just any way. You have to use unconventional techniques to get natural resources.
So come on y’all, we have a great deal to learn about Shale Plays…
Before we even dig into the meat of this blog, let’s get the burning question answered. Why is it called a shale “play”?! There are now several oil shales and gas shales finding favor in the US. Any area of interest or an area that is liked by the oil and gas companies is called a “play.” Thus a shale area of interest is called a shale play. (Mind Blown)
What is the makeup of shale?
Geology.com defines shale as a fine-grain, sedimentary rock that forms from the compaction of silt and clay-sized mineral particles that we commonly call “mud”. Because of its makeup, shale is in a category of sedimentary rocks know a “mudstones”.
What makes shale different than other mudstones? They are fissiled and laminated. “Laminated” means that the rock is made up of many thin layers. “Fissile” means the rock easily splits into thin pieces along the lamination. So, in a nutshell: shale is heavily compacted mud that can break into thin pieces with sharp edges.
What determines to color of shale?
I discovered that there are different colors of shale. Your black shales usually indicate that there is organic material present in the shale. Just a tiny percentage of this material, around 1-2%, can make the shale dark grey or black. When there are organic materials in the dark shale, guess what that can mean? That’s right, oil and gas. There is a catch though…The organic debris has to be heated and preserved the right way for it to produce a natural resource. Shale can also be red, brown, yellow or even green. The coloring really depends on what minerals are present. The colored clay that comes from the shale is used in the bricks for the houses that are popping up all over the Houston suburbs. Shale can also be crushed, mixed with limestone, and then heated. A bunch of scientific stuff happens…. then POOF! You have cement that hardens into the concrete.
What Is Shale Gas?
Basically, shale gas is a natural gas that is present is shale rock. Shale is a rock that the gas cannot flow through easily because the shale is compact or has low permeability. Shale gas and tight gas are both unconventional, because of the elaborate production methods it takes to get them from the ground. Oil shale generally refers to any sedimentary rock that has large amounts of an organic material called kerogen. The kerogen is the part of the rock that breaks down and releases hydrocarbons when heated. The hydrocarbons in oil shale can then be used as an energy resource. Again, oil shale is unconventional because of how we drill for it. The graphic below is a great example of just that:
As stated before, there are so many different rabbit holes we could go down, but I have to have materials for future blogs! I just hope my paraphrasing does all this knowledge justice.
Remember, this was the last part of a three-part blog. You can always go to www.croftsystems.net/blog to read the previous parts of this blog or any of the blogs our company employees have written.
