Here is a great video of a flash flood in Thompson Canyon, which is in Utah and very near these outcrops. This particular video was shot by Doug Jerolmack last summer. I found this on Paul Heller's website, which is a great resource for videos of clastic sedimentation.
[youtube=http://www.youtube.com/watch?v=8t4JVoBtTSs]
Note the debris-rich front of the flow, full of twigs, sticks, and other stuff (pause at 00:19). After some time, the debris-poor part of the flow comes through.
Pause at 00:34 and note the levee of woody debris that has formed on the edge of the flow. This is a defining characteristic of these types of flows and help keep it going by providing additional confinement.
At 00:43-00:47 (end of footage) note the standing wave that has formed.
