- The basic reservoir parameters (thickness, porosity, permeability, saturation, and thermal diffusivity) are fundamentally a function of geology.
- There is some control over viscosity via on injection pressure and temperature; or using a different process such as solvent. That said, maximum operating pressure is still dictated by the fracture pressure of the overburden and pressure of gas and/or water zones. The density and viscosity at reservoir temperature, is not a choice.
- Even well length is dictated by the geology. There is flexibility in where and how long an operator drills their wells, but the reservoir architecture still ultimately dictates well placement.
Thus, comparing raw SOR performance between operators is like comparing basketball skills between people of different heights.
“Who has the best performance?” might be the wrong question, when we could be asking “Who is making the most of the reservoir they have?” Another important question is, which pads are under or over performing? If the two pads are of unequal reservoir quality, simply comparing rate and SOR is insufficient; we cannot tell if the performance is due to better reservoir, or better operations.
HOW TO ACCOUNT FOR GEOLOGY WHEN BENCHMARKING
To properly compare projects, patterns and well pairs, you need a database of well pairs and geological parameters, as well as the processes in place to combine quantitative petrophysical data, core data, production data and qualitative reservoir quality assessments. Fortunately, GLJ can leverage over two decades of experience in the in-situ oil sands space.
Building the data pipelines to combine these different data sources into a digestible format is not a trivial task. Like many oil and gas professionals, I had been doing it manually in excel for years! However, with advancements in automation and data visualization, combining 20 years of data gathering is no longer such a daunting task.
Simply integrating the original bitumen in place, into the production performance analysis will vastly improve the ability to compare different pads and projects. For example, the following is a plot of production, normalized as rate per well pair, and to the first month of steam injection.