Using Network Pathways Through Rock in Oil Recovery
http://www.sciencedirect.com/science/article/pii/0009250981850130
This class is cross-listed between so many majors, and taken by such a wide variety of students because there are so many applications of networks in the real world. This article is a crossover with geology and petroleum engineering. The article briefs the reader on how oil droplets collect in veins in rock. In essence the tiny oil droplets scattered throughout the ground are pushed by water through rock until they all collect in one location. Knowing the location of these collections of oil is one of the biggest businesses in the world, and a good petroleum engineer or geologist will go to great lengths to try to figure out how/why/and where these oil deposits are.
Going into more detail, the article explains that if given two paths, the water will travel through the smaller one if capillary action is the dominant translation method, or the larger one if the water is being moved via a pressure gradient (pushing the oil with it). Using this fact, one can take a cross section of a core sample of rock from an oil field, and then map out the pore sizes as a network, much like out highway graphs in class. With knowledge of the boundary conditions (in order to figure out if the water is moving from capillary action or pressure gradient, thus affecting the path it takes), these scientists can then map out and predict where oil would collect in that sample of rock using, essentially a Nash Equilibrium model for the network, where the water are “drivers” on the highway, the pore sizes are city streets vs highways, etc.
The issue with large scale use lies in the fact that this is a very small scale process. You need microscopic knowledge of the rock, and a map of all the pore sizes to determine where the oil will be, and that is just not practical for the scale the oil industry operates on. However, this paper is still relevant because someday, down the road, we may find an the missing piece to larger scale application or use a different industry/process. It also opens our minds to what is possible with networks, and how they can be used to interpret the world around us.