title: Development of a correlation to correct mercury intrusion porosimetry data
Creators: name: Abiashue, Lucky
Publisher: name: Memorial University of Newfoundland
Year: 2023

description: Analysis of the core data, such as capillary pressure, permeability, and porosity is important in assessing and modeling hydrocarbon flow in a reservoir. Mercury intrusion porosimetry (MIP) method is the fastest and least expensive method of measuring capillary pressure compared to other methods such as centrifuge, porous plate, and vapor desorption. In addition to the injection pressure versus mercury saturation, this method also provides porosity and pore size distribution of the sample. The sample permeability can then be estimated using models with parameters such as capillary pressure, mercury saturation and others. Previous research shows that MICP tests generate saturations curves that are lower than those obtained from other methods. The aim of this work is to improve on the permeability and porosity results obtained using mercury intrusion porosimetry method by comparing them against more accurate measurements such as gas permeametry and porosimetry, and finally develop a correlation based on which the data from mercury porosimetry tests could be corrected. The literature review conducted as a part of this study confirmed that such a correction has not been proposed in the literature. In this research work, MIP method was used to measure porosity and permeability of Nineteen core plug samples from HIBERNIA B16-17, a well drilled offshore Newfoundland and Labrador (Canada). For comparison purposes, the same samples were used for permeability measurement using a more accurate method known as Klinkenberg-corrected gas permeametry. For porosity comparison, some helium pycnometry data were found in the literature for samples collected from the same reservoir / reservoir depth as those of the core plug samples used in this study. In addition, a well-accepted correlation from the literature, known as Swanson model, was used to calculate core plug permeabilities for comparison against measurements. These comparative analyses resulted in improved understanding about the trends and provided correlations between the measurement methods. The resulting correlations can be used to correct the porosity and permeability values obtained from the MIP method and improve accuracy. The comparative analysis conducted in this study shows that the porosity values obtained by helium pycnometry are mostly greater than those obtained by the MIP method with an average difference of 9.8%. In addition, the permeability values obtained from the Klinkenberg-corrected gas permeametry are greater than the results from the MIP method with an average difference of 22.9%. The permeability data estimated by Swanson correlation exhibited higher error when compared to the gas permeametry data, with an average percentage difference of 49.3%. Both the porosity and permeability values obtained from the MIP method are generally lower than the more accurate data collected from gas porosimetry or permeametry; therefore, applying the proposed correction is recommended to generate more accurate porosity and permeability values.