Whole core (full-diameter) permeabilities can be as great as 3- to 4-orders of magnitude greater than in-situ effective gas permeabilities measured on core plugs. Fracturing plays a
major role in the difference with additional influence of confining stress, Klinkenberg effect,
and relative permeability. If the fractures exist in the subsurface then plug data must be used
within a dual-porosity model. If this scale of fracturing is not present in the subsurface, then
whole-core data must be used with care. Detailed well testing can resolve the appropriate
model.

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Last updated June 2004
http://www.kgs.ku.edu/PRS/publication/2001-33/P3-03a.html