Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

C

Empirical coefficient C of the Wyllie-Rose relation.

Porosity

Porosity as a volume fraction.

Swi

Irreducible water saturation as a fraction.

x

Porosity exponent x.

y

Irreducible saturation exponent y.

Estimate permeability in millidarcies from porosity and irreducible water saturation with the Wyllie-Rose power-law relation. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

k

Permeability in millidarcies.

• Aquifer calculations assume a geometry, boundary condition, flow regime, hydraulic properties, well construction, and observation response. Heterogeneity, anisotropy, leakage, storage, partial penetration, recharge, and pumping history can invalidate simple analytical solutions.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

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