"Using digital rocks and pore-scale multi-physics to characterize a sandstone reservoir"
Mita Sengupta, Hess Corporation
ABSTRACT
Digital rocks are 3D image-based representations of pore-scale geometries that live in virtual laboratories. Imaging techniques such as computed tomography (CT), microcomputed tomography (micro-CT), and FIB-SEM (Focused Ion Beam-Scanning Electron Microscopy) can help obtain 3-D high- resolution images of rock samples. These volume-imaging techniques produce data that can be explored using image processing and multi-physics simulations to understand material phases, grain structure, porous networks, and physical mechanisms that occur in them, without having to carry out destructive tests.
Today, we can use digital rocks to complement and expand physical measurements, and gain further insight into the key geologic properties that influence the physical behavior of rocks. We demonstrate the practical applicability of digital rock physics for reservoir characterization, particularly when integrated with physical measurements. In our study, we focus on porosity, permeability, electrical conductivity, and velocity measurements. Physical measurements provide “ground truth” to validate the digital computations. We combine lab measurements with numerical computations to enhance our understanding of multi-physics relationships in a heterogeneous sandstone reservoir.
Digital rock physics is a powerful technique for understanding subsurface processes, and represents a paradigm shift in the field of rock physics. Our study shows that digital rock physics has evolved into a practically usable tool that can, not only bring physical insight into relationships between relevant rock properties, but can also bring quantitative value to real geophysical and engineering problems of oil exploration and production. Digital rock physics re-emphasizes the importance of rock physics as a strategic area of knowledge that builds and strengthens bridges between geology, geophysics and reservoir engineering.