Wellsite Determination of Porosity and Permeability Using Drilled Cuttings


Eric Nigh, Exploration Logging, Inc.
Michael Taylor, Exlog Canada



The availability of porosity and permeability values has been limited to determination by after-the-fact methods, namely wireline logging, conventional core analysis and drillstem tests. Determination of porosity and permeability from drilled cuttings can now be achieved at the wellsite using an advanced formation evaluation system, P-K’". Samples collected one lag time after being drilled can be processed and plotted within thirty minutes to derive porosity and permeability values. These values can then calibrate an online drilling porosity log derived from a drilling model. A P-K calibrated drilling porosity log linked to MWD formation radioactivity and resistivity logs provide the log analyst with the fundamental formation evaluation tools while drilling.