Page 112 - Principles of Applied Reservoir Simulation 2E

Part II: Reservoir Simulation 91

logging, well testing, and 3D seismic analysis. The Macro Scale focuses on data
sampling at the level of core analysis and fluid property analysis. The Micro
Scale includes pore scale data obtained from techniques such as thin section
analysis and measurements of grain-size distribution. Each of these scales
contributes to the final reservoir model.

MICRO

GIGA

Figure 11-2. Reservoir scales (after
Haldorsen and Lake, 1989; reprinted by
permission of the Society of Petroleum
Engineers).

11.2 Integrating Scales - the Flow Unit

All of the information collected at various scales must be integrated into
a single, comprehensive, and consistent representation of the reservoir. The
integration of data obtained at different scales is a difficult issue that is often
referred to as the "scale-up" problem [for example, see Oreskes, et al., 1994].
Attempts to relate data from two different scales can be difficult. For example,
permeability is often obtained from both pressure transient testing and routine
core analysis. The respective permeabilities, however, may appear to be
uncorrelated because they represent two different measurement scales. An
important task of the scale-up problem is to develop a detailed understanding
of how measured parameters vary with scale. The focus on detail in one or more