Abstract
To provide a more reliable assessment of tight and shale formations, it is essential to know their physical properties as they immensely affect the economic production of hydrocarbons from these reservoirs.
In this paper, emphasis will be laid on determining the permeability and porosity of these formations based on laboratory investigation.
To determine the permeability of tight samples, instationary test equipment has been developed and built, including the transient measurement principle. The interpretation of data using this method allows the permeability, effective porosity and Klinkenberg effect to be quantified by means of just a single measurement run. The evaluation of the measured data is carried out numerically via the inverse solution of the differential flow equations. Evaluation procedures and experienced gained in determining the permeability and porosity of various tight materials such as caprock, salt rock samples, tight gas and shale gas cores are fully addressed. In addition, the sophisticated experimental setup will be presented.
Together with the determination of the pure density of samples by helium pycnometer, reliable statements can be derived about the properties of the pore space of the material. Furthermore, the use of mercury porosimetry in determining the porosity and pore radius distribution of the tight samples is also highlighted.
The detailed analysis of the results of the porosity and permeability measurements provide valuable insight for the evaluation of the reservoir with valuable information such as dual porosity behavior.
