A modelling of effects of variable saturation in invaded zone near borehole on neutron tool response in the gas-bearing Miocene formations of the Carpathian foredeep, Poland

► Neutron porosity tool response was calculated for a gas-bearing rock medium crossed by the borehole. ► The invaded zone is defined by a specific hyperbolic function. ► The saturation function is based on the Miocene formations reached in gas-bearing rocks.