Integrated petrophysical uncertainty evaluation impacts reservoir models

摘要

Propagating uncertainty from well logs to production forecasts enables quantification of its effect on other subsurface measurements. Nowadays, 3-D reservoir models play an essential role in the assessment of hydrocarbon resources. They not only are used to estimate in-place volumes but also are the primary input to flow simulation for optimizing and forecasting how much resource can actually be recovered. A 3-D reservoir model is a gridded numerical representation of the producing reservoir intervals. Each cell of the model must contain information about the rock type present at that location along with its porosity, permeability, and fluid saturation. These values are commonly distributed away from the wells using geostatistical modeling techniques. The input data for these algorithms include the interpreted well log values as well as parameters such as proportions of sands, average porosity, geological body dimensions, spatial correlation lengths, porosity-permeability relationships, saturation-height functions, etc., all of which are derived direcdy from well logs and cores.