Just off the White River road (ahem, where I took a wrong turn), these are some of the most beautiful and unusual formations I’ve seen — white minerals in the upper Chadron layer seems to have leached down over the lower layer (yellow and faintly magenta paleosols). These colorful laters represent a layer of sea-floor-deposit Pierre Shale that was exposed to wind/sun/erosion for a long time. Pierre Shale is dark gray when it has not weathered. The layers in this uniquely sculpted formation represent approximately 31 million years of EXPOSURE AND EROSION! The same members are exposed in the Yellow Mounds of Conata basin, but this is the first time I’ve seen them resembling “petits fours glacés” — little iced cakes! The tops are typically mounded, but the sides are vertical, with what appears to be some (limetone?) ledging. I wish the light had been better, as they really were stunning. Reminiscent of translucent cave formations… or maybe a travertine terrace?