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<br /> <br />/ /...-..;.... <br />:~~"<./'~./ <br />/ / ~>; <br /> <br />,-''- <br /> <br />BASE FROM l.Nc:mRECTEO AERIAL <br />PHOTllGRAPHY TAKEN 10/21/84 <br /> <br />" ~" <br /> <br />o 500 <br />I I I', i I I <br />o 150 <br /> <br />/ '. /IS <br />/ ,).. <br /> <br />1000 FEET <br />I <br />I <br />300 I"ETERS <br /> <br />I <br />I <br /> <br />/~ <br /> <br />,A\. <br /> <br />l...,;...........:...i <br />~:::::::::.:::.:::;::;:!J <br /> <br />I AS I <br />I I <br />I I <br />V"///1 <br />~ <br /> <br />RIVER-DEPOSITED OR REWORKED VERY FINE TO MEDIUM <br />SAND (October 21, 1984) <br /> <br />AEOLIAN SAND OR TERRACE DEPOSITS-Silt and fine <br />sand, well sorted <br /> <br />TRIBUTARY DEBRIS FAN-Boulders, cobbles, gravel, <br />sand, poorly sorted; boulders cover more than SO <br />percent of surface area except In tributary streambed <br /> <br />COBBLES AND GRAVEL <br /> <br />TALUS AND BEDROCK <br /> <br />ADDITIONAL RIVER-DEPOSITED SAND (1973) <br /> <br /> <br />EDGE OF WATER <br /> <br />low flow, October 5, 1985,160 m3/s <br /> <br /> <br />High flow, May 20, 1985,1245m3,. <br /> <br />SEPARATION SURFACE <br /> <br />Low ftow <br /> <br />High flow <br /> <br />BADGER CREEK <br /> <br />',..., ',I <br /> <br />/ <br /> <br />. <br /> <br />,< , / <br />~ ""....- <br /> <br />'( <br />.~ '-. ~.. / .' <br />',8', "\: ~ / " <br /> <br />/IS <br /> <br />B .. r' / / <br />-::-l._.~//""';J /;~ / <br />;' /IS ,',,'/ <br />'", .~, ~ ~ <br />.. ......i:..."..,.,>// / <br /> <br />')7' t !>!::~ / <br /> <br />/ .' <br /> <br />'. <br /> <br />JACKASS' CREEK <br /> <br />GENERALIZED SURFACE-FLOW DIRECTION IN <br />RECIRCULATION ZONES <br /> <br />- <br /> <br />Low flow <br /> <br />. <br /> <br />-- <br /> <br />High flow <br /> <br />r::=;) <br />~ '>- <br />RAPID ~ <br />~ <br /> <br />Surlace...flow direction of main current <br /> <br />LIMIT OF BREAKING WAVES (WHITE WATER) AT LOW <br />FLOW-At high flow, breaking waves in main current <br />extend downstream to a point opposite center of <br />recirculation zones <br /> <br />o <br /> <br />DENSE STANDS OF TAMARISK <br />SEPARATION POINT <br />REATTACHMENT POINT <br /> <br />SP <br />RP <br /> <br />Figure 10. Map showing the distribution of unconsolidated geologic deposits at Badger Creek Rapids. Stippled <br />patterns depict the distribution of fine-grained deposits. Figure is from Schmidt and Graf (1990). <br /> <br />The recirculation zone is an effective trap <br />of the suspended load, and eddy bars com- <br />posed of sand, silt, and clay typically fill these <br />zones in Marble and upper Grand Canyons. <br />These eddy bars have been subdivided <br />(Schmidt, 1990; Schmidt and Graf, 1990). <br />Separation bars mantle the downstream side of <br />debris fans and occur near the point of flow <br /> <br />separation. Reattachment bars underlie the <br />primary eddy cell and are highest near the <br />point of flow reattachment at the downstream <br />end of the recirculation zone. Sedimentary <br />structures in these bars demonstrate that bed <br />form migration directions reflect the recirculat- <br />ing direction of the flow (Rubin et aI., 1990, <br />1994b). <br /> <br />. <br /> <br />14 System-wide Changes in the Distribution of Fine Sediment in the Colorado River Corridor... <br />