8267

• UCREFRP Catalog Number: 8267
• Author: Elliott, J. G. and L. A. Hammack.
• Title: Geomorphic and Sedimentologic Characteristics of Alluvial Reaches in the Black Canyon of the Gunnison National Monument, Colorado.
• USFW Year: 1999.
• USFW - Doc Type: Water-Resources Investigations Report 99-4082,
• Copyright Material: NO

Table 3. Sediment-size statistics and critical shear stress for the median particle size, Warner Point study reach
[Station, sample location on cross section from left endpoint; Percentile, percentile of the size distribution; lc, sampled across the entire low-flow channel;
ns, not sampled or not calculated; Critical shear for the median sediment size calculated with equation 2; Shields pazameter is variable depending on pave-
ment and subsurface properties, ft, foot; mm, millimeters; lb/ftz, pound per square foot]
Critical Critical
shear shear
16th 50th 84th Maximum with with
Cross Sample Sample Station Percen- Percen- Percen- particle Shields Shields Remarks
section year code (ft) file file file size param- param-
(mm) (mm) (mm) (mm) eter eter
0.030 0.045
(Ib/ft2) (Ib/ft2)
Vl 1994 XChan lc 90 230 420 1,450 2.33 3.50 Sampled from station 196
to 358.
V 1 1994 LB1dBar 138 60 130 300 700 1.32 1.98
V1 1994 LBank 198 105 240 400 660 2.43 3.65
V 1 1994 RB1dBar 287.5 50 180 370 750 1.82 2.74 Sampled near right edge of
water.
V2 ns XChan ns ns ns ns 740 ns ns Low-flow channel not
sampled.
V2 1994 LB1dBar 66 160 270 400 600 2.74 4.11
V2 1994 LBank 81 100 212 450 600 2.15 3.22
V2 1994 RBank 161 80 125 190 280 1.27 1.90
V2 1994 RSlope 168 55 98 170 380 0.99 1.49 Midway up bar slope.
V2 1994 RB1dBar 186 50 125 200 400 1.27 1.90
V2 1994 ROvrFlo 228 31 140 210 400 1.42 2.13
V2 1995 LBank" 80 34 128 224 410 1.30 1.95
V2 1995 RBank 161 46 98 145 520 0.99 1.49
V2 1995 RSlope 168 52 100 158 225 1.01 1.52
H60 ns XChan ns ns ns ns ns ns ns Low-flow channel not
sampled.
H60 1994 LBank 87 25 130 390 700 1.32 1.98
H60 1995 RBank 172 55 180 333 820 1.82 2.74
H60 1995 RBIdBar 192 65 172 472 670 1.74 2.62
H3 ns XChan ns ns ns ns ns ns ns Low-flow channel not
sampled.
H3 1994 RBank 195 18 90 185 1,000 0.91 1.37 Sample overlaps both V3
and H3.
H3 1995 RBank 196 49 110 191 1,240 1.12 1.67 Sample overlaps both V3
and H3.
V3 1994 XChan lc 5 150 310 500 1.52 2.28 Sampled from station 42 to
205.
V3 1994 LBank 44 2 14 67 370 0.14 0.21 Gravel in backwater of
Boulder Pile Riffle.
V3 1994 RBank 203 18 90 185 1,000 0.91 1.37 Sample overlaps both V3
and H3.
V3 1994 RB1dBar 211 ns ns ns 320 0.00 0.00
V3 1995 LBar 21 41 80 149 2,410 0.81 1.22
14 Geomorphic and Sedimentologic Characteristics of Alluvial Reaches in the Black Canyon of the Gunnison National Monument,
Colorado