porosity in gas shale calculation
I need your help. I have to calculate porosity in shale (potencially gas/oil shale). I have sonic log, GR
, laterolog and neutron log (this one is not calibrated into porosity units, but is in counts/min). All logs are old fashioned Soviet logs only on sheetpapers. Now question: can I freely apply GR to calculate Vsh in shale; and can I apply Willy equation for calculating porosity in shale? Will it be correct? I have many doubts, that's why I ask for help. All calculation have to be done with no software.