Permeability converter
Convert between darcy and square meters, the units of how easily fluid moves through rock.
That's about the same as reservoir sandstone. For water that is a hydraulic conductivity of about 0.00966 cm/s.
What it means
How well does it flow?
Hydraulic conductivity assumes water at 20 °C. For oil or gas the same rock gives a different figure.
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Your permeability in every unit
Learn
Three things worth knowing
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One darcy is about 10⁻¹² m²
Exactly 9.869×10⁻¹³ m². The darcy survives because the SI figure is unwieldy and full of negative exponents.
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Darcy and the fountains of Dijon
Henry Darcy worked out the law of flow through sand in 1856 while designing the water supply for Dijon. Petroleum engineering has used it ever since.
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Permeability is not porosity
Pumice is full of holes but barely lets water through, because the holes do not connect. Porosity is space; permeability is whether it joins up.
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Background
About permeability
Permeability measures how readily fluid passes through porous rock. The darcy is defined so that one darcy passes one cubic centimeter of one-centipoise fluid per second through a square centimeter under one atmosphere per centimeter.
Reservoir engineers work in millidarcy; a good oil reservoir is 100 to 1,000 mD.