Cross check in cross-borehole shows that root-mean-square error of predicted porosity of simple cokriging is less than 10% compared with that of linear re-gression method.
The minimum underbalance is independent of viscosity and compressibility and of reservoir fluids.It is a function of the formation porosity, permeability and radius of perforation channels.
The relative amount of these two kinds of water varies greatly from one kind of rock or sediment to another, even though their porosities may be the same.
Another way to reduce the impact of high winds on tall buildings is to increase their porosity - " cutting out" parts out of the structure and allowing air to flow through, as well as around the building mass.