A measure of rock permeability (i.e., the degree to which natural gas and crude oil can move through the rocks).
a unit of permability. That value which will allow flow of 1 milliliter/sec of 1 centipoise viscosity through 1 cm2 under pressure of 1 atmosphere per cm.
The unit of measurement of rock permeability, i.e. the extent to which it will allow a fluid to flow through it. The permeability of most oil and gas reservoir rocks is measured in millidarcies, (thousandths of a Darcy)