At the summit of Mount Moran a crown
Of Flathead Sandstone still looks down, thrust up
On faulted basement rock. The Miocene
Catastrophe that lifted from the deep
Three thousand feet of buried sediment
Exhumed the Flathead last, and so this cap
Of Cambrian sand, evidence of spent
Primeval seas, survived the ice and rain
That scraped accretion from the continent
Washing eroded sediment down
The igneous cliffs of the uplift block
To meltwater streams and the outwash plain
Fanning the valley floor. The same red rock
Lies buried here, sheared along the fault strike,
Still balanced on a ribbonlike black dike,
But downdropped in the graben, under shale
And bedded seashell, ash and ocean shoal,
Four miles below the floor of Jackson Hole.
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