This post was written by Audrey Sharrock, a Petroleum Engineering Senior. She participated in the MPGE externship program over the summer. 2017 was the first time MPGE was able to offer an externship for our students by working with our close alumni and friends. This program allowed students to gain valuable experience all while working in labs and spaces that are familiar.
Nostalgia and bitter-sweetness has begun to follow me as summer is nearly ending and I approach my last year of college. To say college was difficult would be an understatement. However, the skill-sets, both technical and personal, I have gained, bears testament to MPGE’s incredible faculty, some of whom have tremendously contributed to my successful pursuit and future endeavors in petroleum engineering. I would like to share with you some food for thought.
This summer, I had the privilege to work on a project provided by Devon Energy. My faculty lead was Carl Sondergeld and my mentors were Gary Stowe and Ali Tinni Ouessini. I worked in a team with two other P.E undergraduates; we word in the IC3 lab. Precisely, our work was a quantitative and qualitative analysis of irreducible water saturation from core inventory we received by Devon Energy.We conducted many experiments. Without going into great detail, I’d like to share scratch the surface of what our analysis entailed and what I learned.
We obtained samples from the core received while ensuring the sample set would be an accurate representation of the entire core inventory. We began by oven-drying our samples completely to ensure all mobile/reducible water was in fact, dried; this took upwards of two weeks. Meanwhile, we kept busy running other necessary and resourceful tests to help us better understand the porous media and mineralogy. We quantified mineralogy distribution of our samples by running Fourier Transform Infrared Resonance (FTIR) Spectroscopy. We concluded directly from FTIR that our sample set was very heterogeneous: varied contents of quartz, feldspars, carbonates and clays. We also prepared sample material for a Mercury Injection Capillary Pressure Test (MICP). MICP gave us the pore throat size distribution within a rock sample; it is a function of many petro-physical parameters including sorting and permeability. We concluded from MICP that the entire sample set contained large systems of small pores. Ultimately, we were able to differentiate well-sorted and higher permeability samples from poorly sorted and lower permeability samples.
Honing in on two weeks, all of our samples were completely dry, and we could begin testing for irreducible water saturation. We obtained total porosity by addition of two measurements: connected porosity and fluid filled porosity. Connected porosity of each sample was found by conducting a helium based porosimetry test, where helium is injected at high pressure on a full core plug. Fluid filled porosity of each sample was found by Nuclear Magnetic Resonance (NMR). Without going into great length, NMR is capable to differentiate water from hydrocarbon filled pores, and thus, allowed us the capability to obtain specifically, water filled pore porosity from hydrocarbon filled pore porosity. Ultimately, irreducible water saturation could be quantified once we had the water filled pore porosity and the total porosity.
Once our project was complete, we were asked to present to Devon in Oklahoma City. It was such a privilege to be given the opportunity to share our analysis with industry professionals. I greatly appreciate Dr. Sondergeld for his incredible guidance and support in order to make this happen.
The project was quite extensive and thought provoking. Although this externship program might have been something new, it was absolutely influential in broadening my scope of the industry. The training we received and hands-on daily tasks were a huge contributing factor to my learning. It has been such a privilege to work on this assignment provided by Devon. I owe my newly acquired technical experience in petrophysics to the entire MPGE faculty, particularly Dr. Sondergeld, Dr. Tinni and Mr. Stowe, and of course, Devon Energy. Thank you!