Formation Water Properties
Calculate water density, viscosity, compressibility, and formation volume factor using McCain correlations. Accounts for salinity effects.
Input Parameters
McCain (1991) correlations for formation water properties
Water Density
--
lb/ft³
Water Viscosity
--
cp
Compressibility
--
1/psi ×10&sup6;
Water FVF (Bw)
--
RB/STB
Density (g/cc)
--
Density (ppg)
--
Rs (gas in water)
--
scf/STB
How this was calculated
Water FVF (McCain): Bw = (1 + dVwp)(1 + dVwT), where dVwp and dVwT are pressure and temperature corrections.
Viscosity (McCain): μw at 1 atm from T, then pressure correction applied. Salinity correction factor applied.
Compressibility (Osif): cw = 1/(7.033P + 541.5*S - 537*T + 403300), with salinity in weight fraction.
Gas Solubility in Water: Rsw from McCain correlation, reduced by salinity correction.
Need help with reservoir simulation, waterflood design, or produced water management?
Book a free strategy call →Understanding Formation Water Properties
Formation water (brine) properties are essential inputs for reservoir engineering calculations, including material balance, numerical simulation, and waterflood design. Unlike fresh water, formation water contains dissolved salts (primarily NaCl) that significantly affect density, viscosity, and compressibility. Salinity levels in petroleum reservoirs commonly range from 10,000 to over 300,000 ppm NaCl equivalent.
The McCain (1991) correlations provide reliable estimates of water density, viscosity, formation volume factor (Bw), and compressibility (cw) as functions of temperature, pressure, and salinity. Water viscosity decreases with temperature but increases slightly with pressure and salinity. The formation volume factor accounts for thermal expansion and pressure compression of the water phase. These correlations are implemented in most commercial reservoir simulators. All calculations run in your browser. Built by Groundwork Analytics.