Figure 37. Bed-material grain size, armoring ratios, and lithology for bed-material sampling sites in the Umpqua River basin, Oregon. (A) Median grain size of bar surface and substrate. (B) Armoring ratio at each site computed as ratio of median grain size from the bed-material surface and substrate. (C) Percentage of felsic intrusive clasts. Refer to table 9 and appendix C for particle size and lithology values.

First posted September 29, 2011