ABSTRACT: Methods to Analyze One- and Two-Dimensional Samples for Reservoir Characterization
YUAN, LI-PING, and RUDY STROBL, Alberta Geological Survey, Alberta Research Council, AOSTRA/ARC Joint Geological Research Program, Edmonton, Alberta, Canada
Quantification of the spatial distributions of reservoir heterogeneities is a major task in the reservoir characterization. Variograms have been the most common method to perform such quantification. However, variograms are based on point (zero-dimensional) samples and may not contain some vital information. One example is the reservoir connectivity; i.e. variograms cannot distinguish between a shale formation with disconnected channel sands and a sandy formation with disconnected shales. Sparse point samples cannot provide enough information to determine whether values between samples are continuous.
Linear (one-dimensional) samples, such as sand and shale thicknesses, can be obtained from drilling. Imaging (two-dimensional) samples are usually not available from the target reservoir, however, outcrops with similar lithofacies geometries to the reservoir may be used to quantify the spatial heterogeneity distribution.
Line segment analysis for one-dimensional data and image analysis for two-dimensional data have been applied to quantify synthetic pictures and outcrops. Line segment analysis provides a method for direct use of one-dimensional reservoir data but requires further refinement. Image analysis techniques can adequately quantify the connectivity of the tested examples.
AAPG Search and Discovery Article #91013©1992 AAPG Eastern Section Meeting, Champaign, Illinois, September 20-22, 1992 (2009)