Abstract: Studying the variation of porosity, permeability and the net overburden pressure in formation, can guide the development and modification of oilfields, to statistical and analysis and research on the natural core data of Zhongyuan oilfield by using the newly introduced cmx-300, the core automatic analyzer
developed in late 1980’and applied to study high-pressure porosity and permeability were made. The research shows that the relationship between formation porosity, permeability and net overburden pressure is closely related to univariate quadratic equation; when porosity matches net overburden pressure with exponent relationship, the presented physical significance is clearer, the accuracy requirement can be met and the compressibility of rocks can gained automatically. The compressibility
and average hydraulic radius of the rocks is exponential is put forward; the ratio of permeability under the net overburden pressure and ground permeability is only related to the value of the overburden pressure, but nothing to do with the surface permeability.

Key words: porosity, permeability, net overburden pressure, laboratory testing, Zhongyuan oil field