Is it true that "[sand] grains in the Coconino Sandstone come from the Appalachian Mountains"?

Question

The Creation Museum is a terrifying place for scientists of all stripes. One of their exhibits is the "Flood Geology" exhibit, which purports to explain how a flood of (literally) Biblical proportions circa 6000 years ago explains all the features of the Earth we see today. One panel at that exhibit is titled "Evidences of the Flood in the Grand Canyon":

^{(photo taken by John Scalzi; click for larger, more-readable version - if you think you can handle it)}

This is obviously boneheaded in so, so many ways, but anyway - this panel makes the following claim:

Sand grains in the Coconino Sandstone come from the Appalachian Mountains.

Three related questions:

1. Is this claim true? (The Creation Museum is not beyond telling outright lies, so I have to ask...)
2. If so, how did it get there?
3. How do we determine that a particular grain of sand originates in the Appalachians?

Answer 1

Jeffrey Ralh of Yale and coauthors published Combined single-grain (U-Th)/He and U/Pb dating of detrital zircons from the Navajo Sandstone, Utah, which concludes that Navajo sandstone originated from the Appalachian Mountains. A review of the article is found here: http://www.geotimes.org/nov03/NN_navajo.html.

Rahl et al. propsed that a large river system transported the sediment.

However, Ralh's research concerned only Navajo sandstone, not Coconino sandstone as far as I know.

U–Pb ages of detrital zircons from Permian and Jurassic eolian sandstones of the Colorado Plateau, USA: paleogeographic implications does investigate Coconino Sandstone and other sandstones from the region and discusses what fraction are of Appalachian origin and transport mechanisms.

34% of Coconino Sandstone zircon grains are reported to be of Appalachian origin in table 4.