About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Houston Geological Society Bulletin

Abstract


Houston Geological Society Bulletin, Volume 41, No. 7, March 1999. Pages 15-15.

Abstract: Using Previous HitSeismicNext Hit Attributes to Predict Reservoir Properties-Potential Risks

By

Cynthia T. Kalkomey
Kalkulations, Inc.

Advances in software for generating Previous HitseismicNext Hit attributes and the growing emphasis on production geophysics have led to the widespread use of Previous HitseismicNext Hit attributes as predictors of reservoir properties. Often, we can show-using Previous HitseismicNext Hit modeling or from rock physics-a physically justifiable relationship between a Previous HitseismicNext Hit Previous HitattributeNext Hit and the reservoir property of interest. When this is true, we can reduce greatly the uncertainty of interwell predictions of reservoir properties.

The first critically important step in the use of Previous HitseismicNext Hit attributes is to accurately tie the well and Previous HitseismicNext Hit data-both vertically and aerially. Successful application then relies on identifying a Previous HitseismicNext Hit Previous HitattributeNext Hit that is significantly correlated with the reservoir property being modeled. If found, the dense Previous HitseismicNext Hit data can be used to guide the interpolation between sparse well data using geostatistical, regression, or neural network techniques. The purpose of this process is to estimate volumes of petroleum in place or to make reservoir management decisions such as the location and number of wells, depletion strategy, or gas and water injection operations.

All of the prediction methods-regression, geostatistics, and neural networks-require the interpreter to make inferences from a small number of wells to a larger population assumed to be represented by that sample. Inference should not be based solely on an empirical relationship between a Previous HitseismicNext Hit Previous HitattributeNext Hit and reservoir property derived from the small sample. This study quantifies the probability of observing spuriously high correlations between the well and Previous HitseismicNext Hit data; that is, the probability of observing a significant sample correlation when the Previous HitseismicNext Hit attributes are actually uncorrelated with the reservoir property. If the correlation is indeed spurious and the Previous HitseismicNext Hit Previous HitattributeTop is used as a predictor, not only will the estimated reservoir property be biased, but its error variance will be underestimated. This can lead to highly confident, but very inaccurate, predictions and, ultimately, to poor reservoir management decisions.

End_of_Record - Last_Page 15---------------

 

Copyright © 2005 by Houston Geological Society. All rights reserved.