Ash, Pyroclasts, and Lava. Bottom from the Top Down.

Superposition seems to hold only the layers have slid down into the Colorado River graben. The top here is the bottom of time. The Bridge Springs Ash turns from a lithified tuff to a welded tuff just traversing this ridge alone. And the Horney Toads had it comming.

Norah Jones on YouTube:
https://www.youtube.com/watch?v=Sl_4CVB6EVQ