Sweet San Juan River flood deposits...
Just finished a raft trip on the San Juan between Mexican Hat and Clay Hills, UT (with 48 people!!). The river was in a regulated flood of about 9000 cfs. The flow was laden with the typical assortment of organic debris, tires, sporting balls, flip-flops, and even a refrigerator. However, these beautiful x-laminated flood deposits were perched at least 5 meters above the 'flood' stage indicating that the unregulated San Juan could flex some serious hydro-muscle back in the day. These deposits are in pristine shape and still contain interlaminae of fine organic debris. Possibly the deposits are from a very large and notable flood in October, 1911. It may have exceeded 100,000 cfs.
Related link of interest: http://pubs.usgs.gov/of/2001/ofr01-314/
