Air-saturated formation permeability to air sweep with Klinkenberg correction or Knudsen correction:
(1)
k_a = k_{air}
There is a statistical correlation between initial formation compressibility cr(ϕ)cr(ϕ) and formation porosity which can be picked by various compressibility-porosity models.
See also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petrophysics
[Permeability] [Relative permeability] [Absolute permeability @model]