Date of Award
Master of Science (MS)
David A. Budd
Matthew J. Pranter
James W. Jennings
Previous research into the lateral variability of dolostones’ attributes at outcrop and subsurface interwell scale suggest that variogram properties such as the correlation range and hole-effect wavelength may follow a power-law function with respect to the scale at which sampling is conducted. The research question posed in this thesis is, does a power-law relationship exist between variogram attributes (i.e., correlation range and hole-effect wavelength) and sampling scale across greater magnitudes of scale (i.e. from thin-section to interwell scale). This question was addressed by analyzing the spatial variability of various properties of dolomites at sub-meter sampling scales (thin-section, outcrop slab, and outcrop photomosaics). Porosity and permeability were analyzed on five outcrop slabs and were shown to have either long-range trends or apparent correlation ranges of 4-20 cm and hole-effects with wavelengths of 20-30 cm. Thin-sections were collected from each of these slabs and analyzed for porosity. These sample were shown to have either long-range trends or apparent correlation ranges of 0.2-0.5 cm and hole-effect wavelengths of 2.8-4.6 cm. Outcrop photomosaics were shown to have either long-range trends or apparent correlation ranges of 5-230 cm and hole effects with wavelengths of 70-560 cm.
The data collected herein and previously collected literature data do define a power-law relationship for both correlation range and hole-effect wavelength over several magnitudes of sampling scale. Three possible hypotheses were considered as explanations of this relationship.
Jaecks, Robert, "Spatial Geostatistics, Lateral Variability, and Scale Invariance of Variogram Properties Within Dolomites" (2012). Geological Sciences Graduate Theses & Dissertations. 53.