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<br />the 10 largest boulders were measured at 8 different locations on the debris <br /> <br />fan, within 300ft (90 m) of the buildings reached by the flows. Detai Is <br /> <br />of the sampling method are discussed in the Appendix. The mean boulder <br /> <br />weights at each sample site and the mean weights associated with each drainage <br /> <br />basin are given in Table 3. Note that the boulder \lreights do not: decrease <br /> <br />with distance down the fan i.n Gulches A and B (only one location was sampled <br /> <br />below Gulch C). This lack of sorting with distance from a gully is to <br /> <br />be .expected of debris-flow transport. In contrast, the sizes of boulders <br /> <br />moved much lower on the fan (toward the Roaring Fork Rived by flood water <br /> <br />did appear to decrease with distance from the mouths of the gullies. However, <br /> <br />no quantitative data on boulder transport in this area was obtained because <br /> <br />subsequent clean-up work had removed much of the debris. <br /> <br />Table 3: Mean Weights of Boulders Moved by the Debris Flows <br /> <br />Name Point Weig~~_ lb (kg) Mean Weight lb ( k1';1 <br />Gulch A 1 2450 (1110) <br /> 2 3150 (1430) 1990 (900) <br /> 3 1610 ( 730) <br /> 4 7 ';0 ( 340) <br /> <br />Gulch 13 <br /> <br />5 <br />6 <br />7 <br /> <br />1610 ( 730) <br />7280 (3300) <br />5400 (2450) <br /> <br />4760 (2160) <br /> <br />Gulch C <br /> <br />8 <br /> <br />2450 (1110) <br /> <br />2450 (1110) <br /> <br />Note: Locati,~ns of D\lmbered reference points are indicated <br />on Figure 1. <br /> <br />- 27 - <br />