The Proceedings of the Eighth International Conference on Creationism (2018)

Whitmore and Garner ◀ The Coconino Sandstone ▶ 2018 ICC 615 Figure 46. Roundness scale developed by Powers (1953) and modified by Folk (1955). Figure 47. A comparison of overall grain size and sorting of modern eolian sand dunes with the grain size and sorting of the Coconino Sandstone. Sorting data from modern dunes consists of two sets of data: 465 samples fromAhlbrandt (1979) and 54 samples sieved by Whitmore and his students for a total of 519 samples. Ahlbrandt’s samples were sieved with ¼ phi sieves and Whitmore’s data was prepared with ½ phi sieves. All points are from sand dunes (not interdunes, beaches, etc.). The plot was made with the “R” statistical package and shows the 75, 90, 95, and 99% confidence intervals (R Development Core Team, 2011). The Coconino data was obtained by counting and measuring grains on 80 thin sections; thus the two sets of data were obtained by different methods, but we believe they are comparable. The combined plot shows there is some overlap of the 95% confidence interval between the two plots, but that the Coconino is finer and more poorly sorted than most modern eolian deposits. It is important to note that is is almost no grain-size data from sand waves for which to compare these two data sets.