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, ; that myon ,ights flood .d us- lower gnifi- IS of This j 'dis- ! :yond j 1- i ~ three :sam. and 3edi- :heat silt .on's lit in epo- at of j by .s of oam -like h is j in In's llldy lba- :ers. The e is :>int ere- ,00- um and Be- ave ~ c1t .- G.S. Springer, l.S. Kile /Geomorphology 18 (J997J 9J-JOO ., . 1: i , Except during extreme runoff events, water flow into the caves rarely exceeds rapid drips. During periods of high runoff, much of the runoff bypasses the caves by flowing in surface channels. Water that does reach the caves during high runoff overwhelms the nonnal flow routes and overflows into subsidiary pathways producing many small 'drips and waterfalls. The lack of concentrated recharge and a general screening of larger particles results in minimal input of clastic sediments by water from the valley wall. Hence, the three units that Linton (1992) interprets as tributary-derived slackwater sediments are absent in caves of the Cheat River canyon; the fine-grained sediments are primarily river-derived. To explain the distribution of facies in tributary mouths following the 1985 flood, Kite and Linton (1993) hypothesize that water and sediment dis- charge peaked in the tributaries before the river. When the river reached peak stage and turbidity, the tributaries were discharging a sediment-poor water- mass. A sharp water-mass boundary developed be- tween the turbid river and tributary water-masses and significant deposition occurred only in the Cheat River water-mass. Non-deposition in the relatively sediment-poor, tributary-derived water-masses re- sulted in no sediments being deposited at the height of peak stage by the tributaries (Kite and Linton, 1993). The turbid peak-stage floodwaters of the 1985 flood penetrated the caves of lower Coliseum Rapids, because the caves of the Cheat River canyon did not discharge significant volumes of water with which to create a water-mass boundary. Therefore, unlike the slackwater sediments examined by Kite and Linton (1993) and Linton (1992), the slackwater sediments in caves of the Cheat River canyon are relatively precise indicators of peak stage. The deposition of sediments at a height near peak stage within caves of the Cheat River canyon is consistent with the findings of Kochel and Baker {I 982), Patton and Dibble (1982), and Panon et a1. (1979). Sediments along the Pecos and Devil rivers Were deposited by multiple flood events and con- tained primary structures. Preservation of slackwater sediments appears to be markedly bener in the Texas caves than sediments in the Cheat River caves. In this study, only one cave (Cornwell) contains sedi- ments from multiple flood events. The narrow gap between high water mark and j" 99 slackwater sediments suggests that calculations of paleoflood discharge along humid riven;, such as Cheat River, are possible. The optimum sites to)" preserve accurate stage indicators are not tributary mouths, but inactive caves within the valley wall. Humid rivers may be sufficiently turbid to deposit significant slackwater sediments near peak flood in- undation levels. 9. Conclusions Slackwater sediments deposited in caves of the Cheat River canyon are poorly preserved because of geomorphic setting, cave streams, and unfavorable cave environments. Clastic sediments are being re- moved by scour and altered by biogenic activity. Woody materials decay rapidly because of the moist, warm-cave environment and biogenic activity. Sedi- ments in a cave accurately record peak. stage of at least one high magnitude flood on Cheat River. The best indicators of peak stage for this historic flood are high water IllJITks composed of small styrofoam balls clinging to cave walls and ceilings. Slackw.ter sediments lie less than I m below the styrofoam balls. Acknowledgements The Richmond Area Speleological Society, Cave Conservancy of the Virginias, and Chevron, Inc. provided grants to assist this study. The authors wish to express their gratitude to those organizations. Art Palmer .and Bob Behling provided helpful reviews of an earlier version. We also wish to thank an anony- mous reviewer and G. Roben Brakenridge, both of whom provided instructive reviews of the final manuscript. References Cardwell. D.H.. Erwin. R.B. and Woodward. H.P.. 1986. Geo- logic map of West Virginia. West Virginia Geological and Economic Survey. 2 sheets. scale 1 :250.000. Carpenter. D.H.. 1990. Floods in West Virginia. Virginia. PeDll- sylvonia. and Maryland, November 1985. u.s. Geotogical Survey Water-Resources Investigations Repon 88-4213. Tow- son._ Maryland. 86_ pp. ~ . t ~ [: , , I I i , I I I; i: