The objective of this research is to examine the link between total petroleum systems (TPS), geomodeling and reserves determination with a view to improve production forecasting, and to increase petroleum rates and recoveries while keeping an eye on economics and externalities. Petroleum as used in this paper includes oil, dry gas, and natural gas liquids.
The proposed method links geoscience and engineering through a multi-disciplinary team. Proper understanding of the petroleum system is the foundation for rigorous geomodeling and for increasing economically petroleum rates and recoveries. The idea is not to convert geoscience into engineering or vice versa. Rather the idea is to make sure that members of the team understand properly the data that the other participants need, and that they communicate each other precisely what they need and the form in which the data it must be supplied.
The anticipated outcome is that the interaction will lead to a better understanding of the reservoir(s) and consequently improved forecasting of petroleum rates and recoveries.
Results of the study indicate that engineering deals properly with three essential elements of TPS: reservoir, seal, and overburden rock. However, there is a lack of proper understanding of the first essential element: source rock. Similarly, engineering has a good handle on the fourth essential process of the petroleum system: the accumulation. But there is a lack of proper understanding of the first three processes: trap formation, generation, and migration of hydrocarbons.
This paper looks at filling the gap in this lack of understanding. Having clear knowledge of the type of data needed by engineering from the beginning is important, for instance, when building variograms and performing geomodeling. For example, geoscience can generate 3D geological grids using hundreds or thousands of millions of cells. But engineering can only use in practice a fraction of those cells for simulating multiphase fluid flow. Thus, upscaling and downscaling of the geologic grid is necessary in some cases.
The novelty of this paper is the linking of the TPS, geomodeling, forecasting and reserves determination of unconventional reservoirs. This type of linking leads geoscience and engineering to talk the same language with a view to improve communication. The result is better, faster, and more accurate studies that improve production forecasting, economic rates, and recoveries of petroleum reservoirs.