Coconino sandstone was deposited underwater (Talk.Origins)

Claim CC365.1:


 * The Coconino Sandstone, the origin of which is conventionally attributed to desert sand dunes, was deposited by water. Evidence for this (in addition to the character of fossil footprints therein) includes cross-bedding angles of only 25 degrees, not the 30-34 degrees one expects from desert dunes.

Source:
 * Andrew Snelling and Steven Austin, 1992. Grand Canyon: Startling evidence for Noah's Flood! Creation 15(1): 47.

CreationWiki response:

Please take not that Snelling's and Austin's model isn't the only creationist model to explain the Coconino Sandstone. Whitmore also has proposes a model that claims that it underwent "substratal liquefaction prior to lithification".


 * Whitmore, J., 2005. Sandstone Clast Breccias, Homogenized Sand, and Sand Intrusions: Evidence of Substratal Liquefaction in the Basal Coconino Sandstone (Permian), Grand Canyon, Arizona. Geological Society of America Abstracts with Programs 37(7): 440.


 * 1) The big problem with such conclusions is typical of Uniformitarian Geology, in which they assume conditions similar to today, but a Global Flood such as is described in Genesis would create conditions not observed on Earth today and as such ignoring it will cause errors.
 * 2) There are several lines of positive evidence for underwater disposition and against wind-blown disposition.


 * See: Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.

Furthermore, in support of the substratal hypothesis, Whitmore cites:

1) deformed and homogenized zones in the basal meter of the Coconino containing angular clasts of bedded Coconino sandstone, 2) sand-filled cracks (connected to the Coconino) which penetrate at a downward angle into the Hermit and 3) thin section analysis of the sand-filled cracks showing homogenized, non-bedded sand (typical of sand intrusions).


 * 1) The claim some of the features are distinctive of an eolian environment is on the assumptions of Uniformitarian Geology, which ignores the possible affects of the Genesis Flood.
 * 2) Furthermore, Talk.Origins' source is out of date. A 1990 study by Dr Glen Visher the Professor of Geology at the University of Tulsa in Oklahoma found evidence pointing to underwater deposition and against wind-blown deposition. Such evidence includes:
 * Parting lineations, which is erosion formed by short bursts of fast-flowing water. They have never been observed in desert sand dunes.
 * Evidence for the process by which sand is deposited is found in the differences of grain size found in sandstone. An analysis of the Coconino Sandstone's sand grain sizes were shown be consistent with underwater deposition and not wind-blown deposition.

See:
 * Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.
 * Visher, G. S., 1990. Exploration Stratigraphy, 2nd edition, PennWell Publishing Co., Tulsa, Oklahoma, pp. 211–213.


 * 1) The extent of the sand body is readily explained by the Genesis Flood, which was more than capable of depositing such a large body of sand.
 * 2) In terms of grain size, the degree of inhomogeneity is more consistent with underwater deposition and not wind-blown deposition.

These features are only being interpreted as lee sides based on uniformitarian assumptions. Such high and steep slopes are consistent with underwater disposition in 300 feet of water and a current speed of 2-3.75 miles per hour.
 * See: Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.

Ripple marks are also known to form in water as well as high-angle crossbedding, but the conditions needed for both to occur together violates uniformitarianism.

The most this shows is that some of the sand was dry for a time, and even this assumes they are really rain pits and not air bubbles.

This reference is a little vague, but such steps would seem to result from fluctuations in water current.


 * 1) This assumes that tracks were made during deposition.
 * 2) The fact that the tacks are well preserved shows that they were covered quickly, which would tend to support rapid disposition regardless of  the mode.
 * 3) The sharp definition and clear impression of the tracks tends to support wet sand rather than dry sand, since the cohesion of wet sand holds the form of a track better and longer than dry sand.

This actually supports the water deposition hypothesis since it is consistent with animals trying to get out of rising water. Uniformity would assume that present day processes explain the past, yet present day animal behaviour produces tracks up and down, as well as across the slopes.

While such features are interpreted as inconsistent with water disposition, such interpretations are based on Uniformitarianism and thereby ignore the effects of catastrophic disposition. When catastrophic underwater deposition is considered these features are not a problem for underwater deposition. Actually, the preservation of such features requires rapid burial, so even if one could prove that this sand stone was deposited by wind the process would have had to have been catastrophic. That said there are many features observed in Coconino sand stone that can only be formed underwater, showing that they were underwater.

See:
 * Walker, T., 2003. Paleosols: digging deeper buries ‘challenge’ to Flood geology. CEN TJ 17(3): 28-34.
 * Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.

If a person looks carefully at modern dunes, they will see both the lee side and the windward sides preserved in the bedding planes. The assumed windward side is completely absent from the coconino sandstones. Furthermore, these features are consistent with underwater disposition. Wind ripples are just one way such bed forms can form. They can result from ripples in any flow with a high rate deposition from suspension and can occur underwater. Wind ripples are the common uniformitarian interpretation, but such structures can form underwater.

See:
 * USGS, (n.d.). "Cross-Bedding, Bedforms, and Paleocurrents".
 * Colby College, (n.d.). Bedforms & Sedimentary Structures.
 * Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.

This is Talk.Origins' best argument, because they do refute the argument that the cross-beds slope angle is a problem, but then again it was also the weakest argument in the article.

The fact that most modern sand waves do not produce cross-beds steeper than 10 degrees only shows that the coconino crossbeds were not typical sand waves. Modern sand waves are smaller than what is found in Coconino Sandstone and so do make a good comparison, however a Global flood such as is described in Genesis would have produce larger sand waves and naturally steeper angles.
 * See: Snelling, A. A. & Austin, S. A., 1992. Startling evidence for Noah's Flood. Creation 15(1): 46-50.

This is an interesting conclusion, and a form of Circular Reasoning:
 * 1) They interpret bedding and laminations as resulting from grain-fall because that is how such angles would be produce by wind.
 * 2) They then use this claim of grain-fall bedding and lamination to argue against underwater disposition.