As with many comparison studies, this project started
with the reconciliation of analysis sourced from different
laboratories using different methodologies.
There was a significant business driver to this work as
we noticed differences in porosity and fluid saturations
which contribute to (~25%) difference in hydrocarbon
pore volume among vendors using alternative
techniques. These differences directly impact log
calibration objectives as well as estimations of
hydrocarbons in place.
We began to ask simple questions -- should we use
crushed samples or routine core plugs? What is the
impact of analytical technique on the results? What role
does lithology and organic content play in the results
from different analytical techniques? What is the role of
sample size? What is the variability between vendors for
identical procedures? If there is variability, what is the
Ten twin Permian samples from the Delaware Basin will
be discussed in-depth using a plethora of available
information including X-Ray Diffraction (XRD), Total
Organic Carbon (TOC)/RockEval, Retort, and Dean-
Stark/Gas Research Institute (GRI) protocol analysis from two labs and RCA from one lab. These 10 samples
were picked to represent varying lithofacies with a range
of organic, mineralogical, and water/oil content. The
level of oversight at each data source was also tracked.
Through detailed analysis of the raw data from these
measurements, we address the questions above. With
these results, we hope to 1) maximize every dollar spent
in core analysis, 2) focus oversight where it is truly
required, and 3) accurately and consistently evaluate the
core analysis in the Permian play for fast and value-
driven business decisions.