Work out porosity and permeability instantly with clear inputs, formula shown and shareable results.
Porosity is pore volume over bulk volume - 22% here. Permeability is a different property, estimated by the Kozeny-Carman relation from grain size and porosity: k = d^2 phi^3 / (180 (1-phi)^2). Because grain diameter is squared, fine sand can share a sandstone's porosity while transmitting orders of magnitude less fluid.
Porosity
phi = pore volume / bulk volume
Kozeny-Carman permeability
k = d^2 phi^3 / (180 (1 - phi)^2)
Yes. Clay and chalk have high porosity but tiny, poorly connected pores, so they hold water without transmitting it.
The permeability that passes 1 cm3/s of 1 cP fluid through a 1 cm2 area under a 1 atm/cm gradient - about 9.87e-13 m2.