This report presents a statistical analysis of outcrop-permeability data for quantifying spatial patterns of petrophysical heterogeneity in carbonates that are difficult or impossible to observe in the subsurface. In the study, workers made permeability measurements using plug samples and mechanical field permeameters (MFP) from Permian and Cretaceous shallow-water platform carbonate outcrops in West Texas and New Mexico. The report includes a detailed discussion of factors affecting the accuracy of the measurements and the portability of resulting spatial statistics to subsurface studies.