Crest Operating Company

Petroleum fluid and rock properties are used to determine the physical properties of single phase and multiphase petroleum fluids (Gas, Oil and Water) and their related rock properties from PVT data.  Calculations are based on correlations widely used by the petroleum industry.   Input and  output can be either in English (Oil Field) or SI (Metric) units.

This is a BETA version and has not had exhaustive testing. Please inform our support organization of any issues with this software. This is provided as free software. All software has errors.  While we have tried hard to be accurate Sigma Energy does not guarantee that the results are correct and accepts no responsibility for any errors.



Compressibility Factor  – Z Factor
Gas Properties from Correlations
Gas Properties from Composition
Oil Fluid Properties from Correlations
Water Fluid Properties from Correlation
Rock Properties
Two Phase Volume
Total Compressibility


When entering data in a table on any of the calculators, you must “leave” the last cell for that data value to be included in the calculations.