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<br /> <br />/'., <br />--.J <br />0' <br />:..' <br /> <br />C3:Jses and Impacts of Sa/miry <br /> <br />Erosion <br /> <br />Sc\'er~l n:::~eJ.rcher~[:'i.-lI1 h:l\e' ..ho" n thJ.t I:Cro~lon of sahne ~hales .Ind dl~solutlon of efflorescence <br />(surra..:e ...all') incrca,c ..alinity during thundeNorrm LO\\' elevation ~nowmel{ on s::lhne geologi~ <br />fonnJ.tlon, may al,o contnhutc "lgmfic:.mtly 10 "almlty. .-\nJly..e, of the Green River near the <br />Green RI\t=r. L'tah. Stallon indicate Ih:ll ..alLnity remain, unu~ually high dunng peJ.k flows <br />J..-.."o..:IJted with ~nowmdt runoff events <br /> <br />Reclaffi:.J.!ion ,lUJICS on the ~1cE]mo Creek Sallnlt) Control l'nit found that approxImately J2 per- <br />cent of the 10Ial .-;a]( load could Ix rebted to runoff events. Other slUdies by Reclam:mon show <br />thJt 21 per~'ent of the Pncc Ri\"cr salt load and 1..1. percent of the S..tn RJ.fad River s;:llt load are <br />rdated to natural runoff events. <br /> <br />Stu<..he...{ I:!] conducted on ;-.lancos Shale m the Upper Colorado RI....er Ba...tn have demonstr:lIed a <br />pm.illve rebtion~hlp bct\\een sedIment yield and salt production. Sediment Yield tncreases as a <br />re~ult of t."llher upland erosion or qreambank and gully erosion Upland erO~lOn IS annbuted to nil <br />and inter-nil now Salt and sediment YIelds ..Ire dependent upon stann period. lanJfonn type. and <br />the ~oluble mineral content or the geologIC fonnation. <br /> <br />Smdles[ 1.1] conducted in the Price Ri\'eT Basm have demomtrated that the hlghe..t ...alt :lod <br />sediment concentration,> occur in the first streamflow event following a long penod of no <br />dlscharg.e. The accumulation of salts in the channel is attributed to efllore1>cence resulting from <br />the dr)tng of the channel. Sail yields occurring after the IOlIlal nushmg of the channel 3re Similar <br />10 tho...e found In the surroundmg w:lIersheu sods. <br /> <br />Sediment J.nd the re,>ulting: sail yield are highly dependent upon landfonn type. Three major <br />landfonn types-badlands. pediments. and allu\'Ial valleys-are associated with the ;-.fancos Shale <br />terrain <br /> <br />Badlands are the most erosionally unstable. With sediment Yields as high as 15 tons per acre[I..J.). <br />Rilling accounts for appro'lmate1y 80 percent of the erosion[\3]. Because salt productIon IS <br />closely related to sediment yield and the badland SOils have nol been leached of theIr soluble <br />mmeraJ... they produce the greatest amount of salt of the bndfonn types. <br /> <br />Pediments are genlly Inclmed planate erosIOn surfaces carved in bedrock and generally veneered <br />\\ nh flU\ul gravels. The surface ,>lopes of pedtments are gentle. making them relati\'r.':ly slable. <br />Pediments have deeper SOlis and htgher mfiltr:uion rales than badlands: thus. the) support a greater <br />\egelJ.llon cover and are less erosive. <br /> <br />Allu\'ial \-;llleys are formed by a change m gradient and the deposition of sediment. They are <br />stable e'l;Cept along the channel where headcutllng and gullymg accur. ~losl of the salts hav'c been <br />lea.:hed from the J.l1u\ul deposits: thus. erosion of IhelT landform Iype yield" less salts per unit <br />\olume of sediment th:m the other two landform types. Howe\er. channels lOcised Into allUVium <br />mcorporate both sedIment and salt from sloughed channel banks and salts from efflorescence at the <br />3JJU\ \Urn-bedrock comaClsll~]. <br /> <br />13 <br />