Elizabeth Zuluaga's thesis
by
Elizabeth Zuluaga, MSE
University of Texas at Austin, 1999
Supervisor: Ekwere J. Peters
Measurement of basic petrophysical properties of rocks in situ has always been a challenge
in the well logging petroleum industry. Many logging tools are available to measure porosity in situ such as
Resistivity, Sonic, Neutron, and Density tools. However, quantitative measurement of absolute permeability of the
formation in situ has represented a major challenge. There has been some development of NMR imaging techniques
to derive quantitative values for porosity and absolute permeability. The literature shows validations of
different relationships used to derive petrophysical properties of rocks from NMR techniques. These validations
have only been performed for single, average values of porosity and permeability by comparison with bulk
laboratory measurements. In this research, two practical and quantitative NMR techniques: T1-Saturation
Recovery Technique and Carr-Purcell-Meiboom-Gill (CPMG) multi-spin-echo NMR technique were used to derive
three-dimensional porosity and permeability distributions of three layered heterogeneous Antolini sandstone
cores.
Once porosity and permeability were calculated for small voxels within the sample,
first-contact miscible displacements were performed in the sample and imaged. For further validation of the
petrophysical properties obtained by NMRI, these miscible displacements were then numerically simulated using
the porosity and permeability information obtained by NMRI. A powerful, three-dimensional numerical simulator
was used to simulate the first-contact miscible displacements.
Results show that the NMR imaging techniques and algorithms used to derive the 3D porosity
and permeability distributions of the cores are effective tools for obtaining the petrophysical properties of
highly heterogeneous porous media.
Back to theses index
