The first thing I do when looking into a new play is get an understanding of the geology. It makes sense to me to get a grasp of what makes the play a play. The geographic area of exploration in the Mississippi Lime is north central Oklahoma and into south central Kansas.
What makes this a unique play is that the target rock formations are carbonates rather than siliciclastics or shale, which have been the driving force behind unconventional drilling methods. On top of that, the Mississippian oil trend is a combination of stratigraphic traps (pinchout, reef, and unconformity) producing from relatively shallow depths of 4000 to 7000 feet. These liquids-rich zones were once thought to have been extinguished by vertical, conventional drilling many years ago. Now, with the technological advancements made with horizontal drilling and fracing, operators are able to unlock vast amounts of hydrocarbons. This could be first of many oil plays re-opened for discovery.
With a group of Mississippian aged limestones being targeted here, it will be important to keep in mind which reservoir operators are shooting for. The “Mississippi Chat” consists of weathered limestone, chert, and dolomite deposited in a debris flow. Underlying the “chat” is the Mississippi Lime which was subjected to weathering, digenesis, and erosion. So, depending on where the drilling penetrates, lithologies and reservoir properties will vary throughout the play. However, a great benefit of drilling into these shallow carbonates is that it will be quite a lot cheaper to develop. According to Magnolia Petroleum, a Mississippi Lime operator, lateral lengths range between 2500 to 5000 feet and fractured between 6 and 12 stages. A typical well may only cost around $2.5 million with an average estimated oil recovery around 400 MBOE. Along with infrastructure already in place in and around Oklahoma, this has the right ingredients for a good economic play. Look forward to a follow up to this blog where I will use Drilling Info and DI-Desktop to highlight which, where and how E&P companies are doing in the Mississippi Limestones.