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Line 66: − − [[file:overview-of-routine-core-analysis_fig3.png|thumb|{{figure number|3}}Data compiled from 5300 sidewall core samples indicate that sidewall cores from low permeability formations have an indicated permeability greater than that determined from conventional core analysis. Sidewall cores from formations with more than 20 md permeability consistently have a measured permeability that is lower than that from conventional analysis. (After <ref name=pt05r38 />; data from <ref name=pt05r82 />.)]]
Overview of routine core analysis (view source)
Revision as of 15:05, 17 June 2014
, 15:05, 17 June 2014→Porosity
In samples having a porosity greater than 30%, sidewall core porosity is 1 to 2% lower than conventional analysis porosity. This results from slight compaction that occurs during coring. Medium and low porosity percussion sidewall samples, especially from highly cemented rocks, display porosity that is much too high due to fracturing and grain shattering. The deviation between measured porosity and true porosity becomes greater as the actual porosity decreases. Uncertainty caused by systematic variation in sidewall core porosity relative to plug analysis values can be minimized by development of correlations between sidewall core and conventional core values.<ref name=pt05r38 /> (For more on porosity, see [[Porosity]].)
In samples having a porosity greater than 30%, sidewall core porosity is 1 to 2% lower than conventional analysis porosity. This results from slight compaction that occurs during coring. Medium and low porosity percussion sidewall samples, especially from highly cemented rocks, display porosity that is much too high due to fracturing and grain shattering. The deviation between measured porosity and true porosity becomes greater as the actual porosity decreases. Uncertainty caused by systematic variation in sidewall core porosity relative to plug analysis values can be minimized by development of correlations between sidewall core and conventional core values.<ref name=pt05r38 /> (For more on porosity, see [[Porosity]].)
==[[Permeability]]==
==[[Permeability]]==