<ul><li><strong>The tile.</strong> A square lattice carries the valley floor, the talus aprons and the wash's channel; a skirt drops straight from the outline to a flat base at Z = 0, the valley's red beds in section. The floor stands 0.10 m over the base, 10 mm higher at the back edge and lower at the front, with low drifts over all of it and a field of transverse dunes in the front corner (long stoss slopes, lee faces near the angle of repose).</li><li><strong>The layer cake.</strong> Every formation is cut from the same section, as in Monument Valley: an Organ Rock shale slope and talus apron up to the cliffs' foot, a cliff of De Chelly sandstone in five horizontal beds, a crumbling Moenkopi shale slope, and a Shinarump caprock on top, flat and overhanging the slope by 12 mm. The cliff is 0.28 m of the 0.483 m relief, the slope 0.055 m and the cap 0.028 m, the proportions of the real column (the cliff about two thirds of the relief, the cap a few percent). The beds run flush where they can; a ledge opens only where a strong bed sits on a weak one. Every bed stands as its own rounded band: its face rounds back over the outer fifth of its thickness into a parting 2.3–3.6 mm deep at each bedding plane, so the cliff reads in horizontal strata, the way the plateau's walls do. Each bed carries its own colour, level and continuous round every formation: maroon at the foot where it grades from the Organ Rock, then red-orange, salmon, a pale cream bed, deep red, orange, and a bleached top, each with a dark seam at its parting and a few thin pale laminae. Vertical joints cut into every face but open and close up it (their depth swings between 45% and 100% from height to height), so they never read as one unbroken flute. Desert varnish hangs from the rim and the ledges in a few thin dark streaks, densest high up and fading down the cliff. The Moenkopi slope is red-brown shale in thin beds, a few of them grey-green; the caprock's face is a dark, thinly bedded grey-brown ledge. The caps' tops are weathered slickrock: pale grey-buff where bare, red sand blown over the rest in soft-edged drifts, darker pans where rain stands.</li><li><strong>The formations.</strong> Two mesas at the back, a canyon between their walls; a butte in front, taller than it is wide; a spire that stands to the top of the cliff sandstone, its cap long gone, worn to a totem: its girth narrows fast off the talus (to 58% of its foot's at a fifth of its height), then slowly up a slender shaft, its hardest bed left as a swelling knob under a 34% top, and every parting cut into it. Each formation sits on its own apron and runs 35 mm into it.</li><li><strong>The aprons.</strong> Talus at the angle of repose: 35.0° at the cliff's foot easing to 31.0° at the toe, the concave profile scree takes (measured talus steepens upslope from 31–34° to 35–37°: <a href="https://en.wikipedia.org/wiki/Scree">Wikipedia, Scree</a>; <a href="https://en.wikipedia.org/wiki/Angle_of_repose">angle of repose</a>), then easing into the floor. Scree in the cliffs' own colours: angular fragments of every bed packed with dark gaps between them, coarser pieces among the fine, a few grey caprock chips, chutes of paler debris, and the Organ Rock's banded red-brown shale showing through just under the bench.</li><li><strong>The wash.</strong> It enters at the back edge, runs down the canyon between the mesas and out across the valley between the butte and the spire, and leaves by the front edge, falling 22.5 mm the whole way and never rising. Its bed is read off the floor along its line, held falling, and cut 8 mm under it; a ribbon of buff sand lies on it, rippled across the flow, with gravel bars and cracked mud, its edges run under the banks. On a map, the wash carries on into the next tile.</li><li><strong>Scatter.</strong> 60 fallen blocks on the aprons and at their toes, cut angular by bedding and joint planes and hard-edged, the biggest rolled furthest out, sealed into the talus and held apart. Utah junipers and pinyon as low, broad, lopsided crowns of five dense clumps on short leaning stems, sweeping nearly to the sand; 118 low scrub cushions, big sagebrush silver grey-green with about one in three on the floor rubber rabbitbrush going olive-gold; six cottonwoods turning gold on the wash's banks.</li></ul>
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