Effect of

(Gas, Clays, Overpressure Intervals, Secondary

Porosity, Fractures)

on

Apparent Porosity of Sonic, Density and Neutron

Logging Tools

1

5. Determination of Porosity• Porosity from:

– Acoustic log– Density log– Neutron log

• Effect of:– Hydrocarbons – Shale– Carbonates– Uncompacted Sands – Pressure – Lithology

Sonic velocity and transit times for common rocks and casing

ChartPor-3

Atomic number and atomic weight for formation elements

Actual and apparent densities of formation substances

Detecting overpressuredzone using the

sonic log

Density log in overpressured

shales