Introduction To January Focus: Oil Sands

It is my pleasure to bring to you some fine articles by my friends and colleagues. All these articles were solicited by me for this special section because I have seen the excellent work that these passionate, first-rate geophysicists are doing and I wish to bring their outstanding work to the attention of the wider geophysics community. I asked the primary authors to submit and I am very grateful to all of them and their co-authors for providing such excellent articles. Dragana enriches every project she touches through her passion for and knowledge of geophysics. As a result, interpreting complex reservoirs like the oil sands comes naturally to her. She and her co-authors set the context for oil sands reservoir interpretation in a problem-solving framework. Tammy is an up-andcoming young geophysicist successfully implementing leading edge seismic reservoir characterization technologies. She and Garrett combine these with their geologic grasp of the depositional environment to substantially improve their understanding of their reservoir and unlock its value. We all need to learn to demonstrate the real value of geophysics. Their paper is particularly important because they demonstrate the economic value of geophysics for their play. I have been admiring Ted’s microseismic work since the late 90’s. Microseismic is going to be an important tool in the future of the oil sands. Ted continues to be on the forefront of every practical advancement in microseismic. He and Katie show that recent advancements in microseismic evaluation have important applications in oil sands. I encourage you to read the articles in this January Focus on Oil Sands and learn what these incisive geophysicists would like you to know.

Dragana, Jan, and I (Strategies to fill in the details for an oil sands reservoir: Kinosis example) provide the theme for the section with the idea that “the key is to ask the data the right questions about the reservoir”. All of these articles follow that problem solving paradigm. Dragana, Jan and I develop the concept of oil sands interpretation as a problem solving exercise. Focus on the basic problem(s) you are trying to solve. Conventional interpretation is just the starting point, building the skeleton for the material interpretation, which is expanded through attributes and then focused problem solving for reservoir characterization fleshes out the skeleton to find where the bitumen is and what is around it.

Tammy and Garrett (Characterization of the Albian Lower Grand Rapids Formation, Cold Lake, Alberta) employ these concepts to add real value to their oil sands play. Tammy uses joint PP and PS pre-stack inversion to derive density. Density fleshes out the conventional interpretation to differentiate bitumen sands from mudstones. They show how the combination of the inversion with conventional seismic interpretation and depositional models brings clarity to the understanding of their reservoir. The result is a much clearer pay map, which is in line with the geologic understanding of the area. A geologically sound pay map will allow them to develop this reservoir optimally, increasing its value to the company.

Microseismic will be a significant tool in the future of oil sands developments, primarily because of concerns about caprock. Beyond that, Ted and Katie (Microseismic Monitoring Applications in Heavy Oil Reservoirs) show it has many more uses in oil sands reservoirs and demonstrate that it will be a valuable tool to infer reservoir behavior. Microseismic monitoring has been rapidly developing new techniques through it use in hydraulic fracturing. It is no longer “dots in a box”. These new techniques are relevant for oil sands reservoirs. Ted and Katie show several examples of what can be done today using microseismic monitoring in oil sands reservoirs, including seismic moment tensor inversion that shows changes of maximum stress direction with depth in an oil sands reservoir. They demonstrate that failure mechanisms, e.g. tensile, shear, explosive, implosive, etc., can be determined and that the failure mechanisms help us to understand how the steam chambers are evolving.

I hope that you enjoy reading these articles as much as I have. I am very grateful to these authors for sharing some fine geophysics with all of us. I use or I am trying to use all of the techniques described here in our oil sands plays and elsewhere. It is my aspiration that these articles will give you a leg up on where oil sands geophysics is going and that you will be able to use these techniques too.

Cheers,
David Gray