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<br />22 <br /> <br />The difference in time scales between Figure 2 from Wolman"and <br /> <br />Leopold (1957) and Figure 16 is of interest. The high rate of accretion for the <br /> <br />Green River d~posit is probably due to the close proximity of this deposit to the <br />main channel, and the high levels of suspended sediment carried by the Green <br />River. Figure 2 (Wolman and Leopold, 1957) shows accretion over a 2000-yr <br /> <br />period, but it was constructed using several assumptions, including: (1) no <br /> <br />change in flood frequency over time, (2) identical thickness of sediment <br /> <br />deposited for each overbank event, (3) bed elevation being constant over time, <br /> <br />and (4) no change occurring in the stage-to-discharge relation over time. Our <br /> <br />data show, in fact, that none of these assumptions are completely valid for the <br /> <br />Green River study area. Figure 16 offers a detailed picture of the building of an <br /> <br />actual deposit and provides considerable insight into the process of vertical <br /> <br />accretion. <br /> <br />Effective Discharge and <br />Landfonn Response <br /> <br />Few studies have linked the concept of effective discharge with the <br /> <br />actual processes that create fluvial landforms. Thus, the appropriate time <br /> <br />domain over which effective discharge should be calculated is unknown. We <br /> <br />calculated the moving effective discharge based on 10 prior years of flow <br /> <br />conditions (Fig. 17). Effective discharge is a continually changing value when <br /> <br />calculated in this way, due to the large variability in flood magnitudes over long <br />