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In page Geology of the Grand Canyon area:

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Formations of the Supai Group are from oldest to youngest (an unconformity is present at the top of each): Watahomigi (see 5a in figure 1) is a slope-forming gray limestone with some red chert bands, sandstone, and purple siltstone that is 100 to 300 feet (30 to 90 m) thick.[6] Manakacha (see 5b in figure 1) is a cliff- and slope-forming pale red sandstone and red shale that averages 300 feet (90 m) thick in Grand Canyon.[7] Wescogame (see 5c in figure 1) is a ledge- and slope-forming pale red sandstone and siltstone that is 100 to 200 feet (30 to 60 m) thick.[8] Esplanade (see 5d in figure 1) is a ledge- and cliff-forming pale red sandstone and siltstone that is 200 to 800 feet (60 to 200 m) thick.[9] An unconformity marks the top of the Supai Group.