Beginning in 1973, we pioneered integrated petrophysics for reservoir description in support of field, pool, and basin studies, and in productivity analysis from logs and cores in support of reservoir simulations. More recently, we have developed unique solutions for unconventional reservoirs and for calculation of rock mechanical properties for stimulation design and seismic attribute interpretation.

Although Ross Crain, P.Eng. has retired from professional practice, his experience and methods continue in the capable hands of Dorian Holgate, P.Geol. See Dorian's resume and contact info HERE.

"The cheapest oil you will ever find is already in your well files. Use some high-quality petrophysical analysis to help you find it.



These analyses require accurate and calibrated values for shale, porosity, mineralogy, saturation, permeability, and natural fracture intensity, controlled by sample, core, geochem, XRD, test, and production history data. A good analysis integrates and reconciles ALL available data, and updates to reflect new data are a normal part of the job.

Unconventional reservoirs need specialized analysis models specifically tailored to the situation. Most conventional petrophysical software does not have the appropriate code built-in, so custom code is required. Check out Crain's Integrated Petrophysics Courses to find successful solutions for tight gas, tight oil, gas shale, oil shale, tar sands, coal, coal bed methane, gas hydrates, geothermal energy, potash, low resistivity, radioactive, laminated sand-shale, laminated porosity, metamorphic, igneous, and volcaniclastics. Don't forget to calibrate to ground truth specific to your project -- methods and parameters that worked in one play probably won't work in another, no matter how similar you think the projects may be.

When the petrophysical analysis has been properly calibrated, add calibrated mechanical properties models to aid stimulation design for a complete picture of your reservoir. Not sure how to do this? Check out Crain's Integrated Petrophysics Courses for straight-forward solutions.

Here's an example of what you should be looking for.

Example of a deterministic petrophysical analysis in a shale gas with relatively low clay and kerogen volume. TOC weight %, core porosity, core oil and water saturation, core permeability, and XRD clay and dolomite values are shown as coloured dots. The dark shading in Track 4 is the kerogen volume, red shading is free gas, and blue is irreducible water. Since the zone is radioactive due to uranium, clay volume is difficult to capture from logs unless a spectral gamma ray log is run, as was done in this well. XRD clay volume is used to calibrate this result. Similarly, the other minerals, kerogen, porosity, and water saturation are calibrated, step-by-step, to obtain a good match to all the "ground truth".


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