Changes

==Reservoir Permeability==

==Reservoir Permeability==

[[File:Average permeability.jpg|300px|thumbnail|right|{{figure number|1|}}Average permeability for various producing fields on the UK and Norwegian continental shelves.<ref>Spencer, S. J., M. L. Somers, W. V. Pinczewski, and I. D. Doig, 1987, Numerical simulation of gas drainage from coal seams: SPE Paper 16857, 1987 SPE Annual Technical Conference and Exhibition, Dallas, Texas, p. 27-30.</> (Gluyas et al. 2004; Abbots 1991; Gluyas et al. 1992; Oxtoby et al. 1995).]]

[[File:Average permeability.jpg|300px|thumbnail|right|{{figure number|1|}}Average permeability for various producing fields on the UK and Norwegian continental shelves.<ref>Spencer, S. J., M. L. Somers, W. V. Pinczewski, and I. D. Doig, 1987, Numerical simulation of gas drainage from coal seams: SPE Paper 16857, 1987 SPE Annual Technical Conference and Exhibition, Dallas, Texas, p. 27-30.</ref> (Gluyas et al. 2004; Abbots 1991; Gluyas et al. 1992; Oxtoby et al. 1995).]]

Permeability is an intrinsic property of a material that determines how easily a fluid can pass through it. In the petroleum industry, the Darcy (D) is the standard unit of permeability, but milidarcies (1 mD = 10-3 D) are more commonly used. A Darcy is defined as a flow rate of 10-2 ms-1 for a fluid of 1 cp (centipoise) under a pressure of 10-4atm m-2. Permeability in reservoir rocks may range from 0.1 mD to more than 10 D.<ref name=gluyas2004 />

Permeability is an intrinsic property of a material that determines how easily a fluid can pass through it. In the petroleum industry, the Darcy (D) is the standard unit of permeability, but milidarcies (1 mD = 10-3 D) are more commonly used. A Darcy is defined as a flow rate of 10-2 ms-1 for a fluid of 1 cp (centipoise) under a pressure of 10-4atm m-2. Permeability in reservoir rocks may range from 0.1 mD to more than 10 D.<ref name=gluyas2004 />