1999 Conference Abstracts

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1999 Abstract: Bhattacharya et al.

From Geomodels to Engineering Models— Opportunities for Spreadsheet Computing

Saibal Bhattacharya, W. Lynn Watney, John H. Doveton
Willard J. Guy, Geoff Bohling
Kansas Geological Survey
1930 Constant Avenue – Campus West
Lawrence, Kansas 66047


Data used to build reservoir models come from different scales, such as core, log, well tests, pressure and production profiles, and seismic; thus they carry the inherent need for calibration to a common scale. Unfortunately, as no accepted procedure is available to solve this calibration problem, doubts remain about the representativeness of the data that are often used to describe a reservoir model. In the absence of a standardized upscaling method, a series of procedural steps, described in this paper, can be employed on data gathered from different sources to test and build a coherent reservoir model. Each step in this procedure is a part of an iteration loop that checks for consistency and coherency among the available data. In case of a mismatch, the process encourages the user to go back to the previous step or steps and revise one or more of the relevant assumptions. The method outlined in this paper, the Super Pickett crossplot, integrates data from different sources such as cores, well logs, and well performance to build a volumetric geomodel that is then used to validate the mass balance calculation. The strength of this method lies in the fact that the major elements (the Super Pickett plot, the volumetric and material balance calculations) of the process can be performed in a spreadsheet environment, making it both cost effective, versatile, and portable. This exercise enables the building of an internally consistent geo-engineering model representing the reservoir. Such a model can be used effectively as the basis for reservoir simulation studies.