Waterflood Recovery and Fluid Flow Upscaling in a Shallow Marine and Fluvial Sandstone Sequence

Abstract

Detailed reservoir characterisation and modelling has been an active area of petroleum technology development for several years now, but incorporating and scaling up these geologic models into fluid flow and production simulations is a major challenge. The objective of this study is to properly incorporate all relevant levels geological heterogeneity identified in a detailed outcrop reservoir description into a flow simulation of an hypothetical reservoir. We apply the "geopseudo" upscaling methodology to the geological description of a shallow marine sequence exposed in the Book Cliffs. The study identifies which features are important for field-scale fluid flow and recovery for a waterflood.A cross section waterflood flow simulation, using the geopseudo upscaling technique, was carried out on an interpreted cross-sectional panel through a portion of the Book Cliffs outcrop in Utah. The section consists of the following lithofacies: Undifferentiated Upper Shoreface deposits, Hummocky Cross Stratified sands, the Swaley Cross Stratified sands, Fluvio-Tidal Channel Sandstones and two units of Heterolithics. A grid block size of 10 metres by 1 metre was used, with two stages of upscaling to account for the effects of small-scale heterogeneities. The thin beds of shales were accounted for using vertical and horizontal transmissibility multipliers between grid blocks. Sensitivity runs were carried out to assess the relative contribution of different geological parameters to the waterflood performance.

Quantitative Outcrop Data for Flow Simulation

“…However, these pictorial records are difficult or impossible to incorporate into the gridded data structures required for reservoir simulation. Modeling of fluid flow through heterogeneous hydrocarbon reservoirs and aquifers requires a more structured integration of stratal geometry and rock property observations, and a greater emphasis on unambiguous quantitative prediction of petrophysical variations throughout the deposit (e.g., Anderson 1989;Dreyer et al 1993;Ciametti et al 1995;Koltermann and Gorelick 1996;White and Barton 1999). Some types and scales of geologic variation may have little influence on fluid flow, whereas other variations may be critical to accurate prediction.…”

The Effect of Discontinuous Shales on Reservoir Performance During Immiscible Flow

“…Their effect on two-phase fluid flow is less well understood. Other studies 10,11 have suggested that oil located in the junction where two shales intersect is bypassed by the displacing fluid; in this case, the oil remains trapped by the shales (fig. 1b).…”

Upscaling of Unstable Miscible Displacements and Multiphase Flows Using Multiresolution Wavelet Transformation

“…They computed the effective properties for the geological units at the geostatistical scale by up-scaling from a small-scale description, and the properties at the simulation scale from a second up-scaling using the effective properties from the first step as input. Similar approaches were used earlier by Ciammetti et al 15 and Stephen et al 16 in which the effect of very small-scale heterogeneities was included in the generation of the pseudo-functions for various geological facies. A review of application of the pseudo-relative permeabilities for up-scaling is given by Barker and Thibeau 17 Barker and Dupouy 18 present a comparison among five different methods of dynamic pseudo-relative permeabilities.…”

“…The densities o ρ and w ρ are evaluated under the standard conditions. We then combine Eqs (15). and(16)to obtain a single equation for P o which contains no explicit time derivatives of the phase saturations:…”