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<br />W <br />I-' <br />..... <br />-1 <br /> <br />pediments and alluvial valley floors. A similar classification system <br />was developed by SChafer (1981) in the Woodside, Utah area. Johnson <br />prepared a 'geomorphic map that shows the distribution of these landforms <br />between Grand Junction and the Colorado Utah boundary (Fig. 3-3). The <br />dissected pediments and alluvial valley floors of this three-part <br />classification can be readily identified. However, within the areas <br />designated as badlands there are miniature pediments at the base of <br />eroding hiUslopes, as well as small alluvial valleys and incised <br />channels. <br /> <br />, <br />:i <br />-'j <br />.~ <br />~ <br />I <br />.~ <br /> <br />Badlands <br /> <br />Ie <br /> <br />I <br /> <br />Badland topography comprises the largest part of the area. The <br />cross sections of Figure 3-4 show the characteristic appearance of this <br />rugged landscape. The badlands have variable relief and high drainage <br />density (Figure 3-4). In fact, three types of channels have developed, <br />and from largest to smallest, they are as follows. l) upland channels, <br />that originate in the plateau behind the 800k Cliffs; 2) channels that <br />extend up to the Book Cliffsl 3) channels that originate on the piedmont <br />at the base of the Book Cliffs. There are of course tributaries to <br />these main channels, and rills develop on the hillsides. <br />To develop a quantitative description of portions of the badland <br />terrain Johnson (1982) selected 8 small drainage basins for detailed <br />analysis (Fig. 3-5). 8asin T is a tributary of an upland channel (West <br />Salt Creek), Basins N, P, and Q drain into a piedmont tributary of Leach <br />Creek, and 8asins A, R, 5, and U are tributaries to piedmont channels <br />(Fig. Ib). The flow in nearly all channels in the area is ephemeral in <br />response to high intensity summer thunderstorms. <br />Examination of the tributary basins indicates great variability in <br />inter- and intrabasin characteristics. In all cases, basin length is <br />greater than basin width, but basin size, shape, and relief vary widely. <br />Basin area ranges from 22,000 m2 for 8asin Q to 340,000 m2 for Basin T <br />(Table 3-l). Relief varies from l5.2 m to 84.7 m for Basins Q and T, <br />respectivelY. The lowest relief-length ratio occurs for 8asin 5 with a <br />value of 0.052, while the highest is for 8asin U with a valve of 0.097. <br />Basin P hi:ls the lowest main channel gradient (3.64%) and Basin U the <br /> <br />35 <br />