-Physics of Drilling-

Substances in reservoirs deep under the surface of the earth experiences tremendous amounts of pressure as a result of being sandwiched between enormous masses of earth, when a well is drilled the primary driving force of the substance up the well is this pressure which acts radially into the production well. However as the volume of substance in the reservoir decreases the magnitude of the pressure in the reservoir decreases reducing amount of substance produced. On top of that as the substance drains the reservoir rock begins to collapse on itself, reducing permiability, the stability of the reservoir and the rate at which the substance is produced. The solution is an injection well that helps slow the loss of pressure, where a pump on the surface injects a substance, steam used in figure 4-4, under rediculously massive amounts of force into the reservoir. However there is still a chance of damaging the reservoir rock if the injectant is pumped into the reservoir at too high of a pressure. In this picture the substance in the reservoir is heavy viscous oil, the steam is used as the injectant in this example because the heat radiats into the surrounding heavy oil making it lighter in order to increas production. While drilling the well head topside has to supress the pressure of the reservoir properly in order to continue drilling. This video shows what happens when that pressure is accidentally released. The dangerous gysers that result are know as blowouts.