Questions Why do core and log porosities sometimes not match?What is the difference between total and effective porosity?How many different definitions of effective porosity exist? Recommendation Measure total porosity values on cores at reservoir-representative net confining stress and use these values to correlate total porosity derived from logs.If your model calls for the use of effective porosity, subsequently adjust the core-correlated log total porosities.Ensure your definition of effective porosity is consistent within your team for a given reservoir.
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