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Coconino Sandstone is a geologic formation that spreads across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah.
This rock formation is particularly prominent in southeastern Utah, where it can be seen in a number of national parks and monuments, including Zion National Park, Capitol Reef National Park, the San Rafael Swell, and Canyonlands National Park. It is also present in the Grand Canyon, where it is visible as a prominent white cliff forming layer. Coconino sandstone frequently appears just below the Kaibab Limestone or the Toroweap layer. Coconino layers are typically buff to white in color, argued by many to be the remnants of eolian (wind-deposited) sand dunes deposited approximately 260 million years ago (McKee 1979)
Young and Old Earth creationists, i.e. Dr. Leonard Brand, have argued that fossil tracks in the Grand Canyon's Coconino Sandstone point to a more recent underwater deposition, rather than desert wind deposition of dry sand. Because many of the tracks have characteristics that are "just about impossible" to explain unless the animals were moving underwater, Dr. Leonard Brand has suggested that newt-like animals made the tracks while walking under water and being pushed by a current. To test his ideas, he and his colleague videotaped living newts walking through a laboratory tank with running water. All 238 trackways made by the newts had features similar to the fossilized trackways in the Coconino Sandstone, and their videotaped behaviour while making the trackways thus indicated how the animals that made the fossilized trackways might have been moving. Putting together all of his observations, Brand and Tang (1978) thus came to the conclusion that the configurations and characteristics of the animals trackways made on the submerged sand surfaces most closely resembled the fossilized quadruped trackways of the Coconino Sandstone. Indeed, when the locomotion behaviour of the living amphibians is taken into account, the fossilized trackways can be interpreted as implying that the animals must have been entirely under water (not swimming at the surface) and moving upslope (against the current) in an attempt to get out of the water.
Brand and Tang’s (1991) failed to demonstrate an underwater origin for the Coconino Sandstone as discussed by conventional paleontologists, i.e. Lockley (1992), Loope (1992), and Lockley and Hunt (1995). For example, Brand and Tang’s (1991) research completely overlooks the effects of microbial crusts that form when microorganisms grow in the upper several millimeters of a dune when moisture from dew and mist that dampen the sand during the night. They quickly create a crust, which have the properties of wet or damp sand. Because Brand and Tang (1991) did not replicate such crusts in his experiments, his experiments fail as an accurate comparison between how footprints would be preserved in sandy substrates of varying moisture conditions. They found that evident toe marks and sole impressions can form in sand of different water content. The difference in the substrates that they found is the relative percentages of these marks formed in different substrates, which can effected can be effected by a wide variety of factors that Brand and Tang (1991) failed to account for in their research. Also, the ancient vertebrates, which made the Coconino tracks were not salamanders, differed significantly enough from salamanders that salamanders are not appropriate models in terms of behavior or tracking making processes. For these and many other reasons, conventional paleontologists, i.e. Lockley (1992), Loope (1992), and Lockley and Hunt (1995) all disagree completely with Brand and Tang’s (1991) interpretations. Instead they argue that these tracks were clearly made in dry sand.
Reference Cited
Brand, L.R. and Tang, T., 1991, "Fossil vertebrate footprints in the Coconino Sandstone (Permian) of northern Arizona: Evidence for underwater origin." Geology, vol. 19, pp. 1201–1204.
Lockey, M.G., 1992, "Comment: Comment and Reply on "Fossil vertebrate footprints in the Coconino Sandstone (Permian) of northern Arizona: Evidence for underwater origin"" Geology. vol. 20, no. 7, pp. 666-667.
Lockey, M., and A.P. Hunt, 1995, Dinosaur Tracks and Other Fossil Footprints of the Western United States. Columbia University Press.
Loope, D.B., 1992, "Comment: Comment and Reply on "Fossil vertebrate footprints in the Coconino Sandstone (Permian) of northern Arizona: Evidence for underwater origin"" Geology. vol. 20, no. 7, pp. 667-668.
McKee, E.D., 1979. "A study of global sand seas: Ancient sandstones considered to be eolian." U. S. Geological Survey Professional Paper 1052, Reston, VA: USGS.