Page 141 - Reservoir Formation Damage

Characterization of Reservoir Rock 123

and therefore the deviations of the measured and estimated rock properties
are given by:

e = f-f* (6-14)

Then, Chakrabarty and Longo (1997) determine the goodness of the
estimates of the mineral fractions by the following sum of the squares
of the deviations:

(6-15)

As stated by Chakrabarty and Longo (1997), the chemical laboratories
measuring the rock properties usually also provide the standard deviations
of the measured properties. Similarly, the service companies running the
wireline logs can provide the standard deviations of the geochemical well
logging. They suggest that the XRD pattern can provide the initial
estimates of the mineral fractions. Otherwise, a reasonable initial guess,
such as evenly distributed mineral fractions can be used.
Chakrabarty and Longo (1997) demonstrated their method, called the
modified matrix algebra-based method, by several examples. Chakrabarty
and Longo (1997) show satisfactory comparisons of the measured and
predicted properties of the various rock samples.

References

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