Petrographic coded correlations in petrophysics - Comparison and declaration of physical rock properties from experimental measurements
Research output: Thesis › Doctoral Thesis
Physical rock properties and correlations of these properties for various distinct lithologies define key parameters for geological, geophysical and engineering applications. Numerous rock types of different geological units and formations from eastern Austria were therefore sampled. Measured lithologies comprehend carbonates, sandstones, igneous- and metamorphic rocks. Diagrams of directional petrophysical parameters as a function of porosity show trends for the main lithology groups. Formation factor used as resistivity value, was correlated to other petrophysical properties like permeability, seismic wave velocities and thermal conductivity. New insight into the pore space of numerous samples is presented by scanning electron microscopy and Computer tomography. The anisotropy of the directional petrophysical parameters was also calculated and correlated. These correlations are identified for formation factor and permeability and for seismic velocities and thermal conductivity because they are largely controlled by the pore space and the mineral framework respectively. Model calculations had also been assessed for the elastic parameters of all lithological subgroups. Bound models were used to test the elastic parameters and a new model-based approach was used to classify the lithological groups further into subgroups. The new classification was then successfully tested for the automatic approach. This automatic approach was finally tested for different starting parameters and the resulting correlation of compressional- and shear modulus showed that the classification worked better for the empirical starting parameters. Magnetic measurements of the anisotropy of magnetic susceptibility (AMS) were conducted for some selected samples. AMS measurements were conducted together with the aim of estimating pore space properties using the Ferrofluid impregnation method. Insights into mineral- and pore space structures and anisotropies of measured samples was gained. The AMS data was finally correlated to the experimental data and the pore space data.
|Translated title of the contribution||Petrographisch kodierte Korrelationen in der Petrophysik - Vergleich und Deklaration von Gesteinseigenschaften basierend auf experimentellen Messungen|
|Publication status||Published - 2019|