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94 G.S. S"ri"l'''. ).8.. Ki.. ! Geomorphology J 8 (J997i 9 J - JOO are bounded by scounurfaces and display sedimen- tary structures not observed in texturally similar phreatic facies sediments. Overbank sediments can be differentiated from cave stream sediments by sedimentary structures, distribution of facies relative to input points, and particle size. The Cheat River canyon is uninhabited. Modern anthropogenic materials within the caves can be attributed to historic overbank deposition by the river because the towns of Albright and Row]~sburg, up- stream of the canyon, were largely destroyed by the 1985 flood and contributed to a recognizable subfa- cies of overbank flotsam. This flotsam contains a wide diversity of materials (such as housing materi- als and toys), dissimilar to deposits of beverage containers, styrofoam, and general litter commonly found along major rivers. Modern and paleoflood overbank deposits were recognized in ] 0 caves. Loamy silts are the dominant overbank sediment encountered in the caves. Very fine sands were observed in two caves. Large woody debris (flotsam) is volumetricaJly the largest compo- nent of modern overbank deposits in caves near Cbeat River. ~N o 20 40m Flotsam Roc!< Cave 3.5 5. Description of selected overbank deposit locali- ties Darby Pit: The entrance to this cave is 3 m above Cheat River. The cave is a 45 m long, linear stream passage developed at the same elevation as Cheat River. The cave floor is composed of loamy silts to matrix -supponed loamy gravels. The banks of the stream are lined with bioturbated, lenticular deposits of loamy silt deposited by floodwaters from Cheat River. Individual slackwater deposits are indistin- guishable. South Side Cave: The entrance to this cave is a spring located 0.6 m above Cheat River. The cave consists of B shon, linear stream passage developed perpendicular to the river. The cave stream is derived from a surface stream sinking on the valley wall. The cave floor is bedrock with shon stretches of gravel. Fine sands, I 10 2 cm thick, are frequently deposited in the cave by flooding of Cheat River. The cave stream removes these deposits in :s 7 days; fine- grained sediments are not preserved in the cave. Coliseum Rapids: The most extensive deposits of overbank sediments are in caves at lower Coliseum Rapids, a 400 m long, bedrock-lined reach with 1M.. = ~ig'!t of cave above I nver m meters Rse ~.lL ~yiftRapids H.. Tim's Climb Cave -.~ . ..... CTc;.7..--........---./ .. ~ -' - -- _Jowcliff Fig. 2. Caves of lower Coliseum Rapids. FPC is Flotsam Point Cave, RSC Rubber Softball Cave. AH Airtight Hole, and ere Coliseum Tube Cave. Cheat River is 40 to 60 m wide. Only Tim's Climb Cave was not inundated by the 1985 flood. boulders u seum Rapi of the Pric rapids is a exposed all caves are j the outside the caves .a rarely inun of these ca Flotsam above Chel the 1985 f slopes abo posited by the cave ar Flotsam above Che recurrence Stra o ~. . j 20 - . " " . " 40 - ~ ..,.. 60 ~ Svmbol Vadose ~Gr: IT] Ov Ge. - WI Fig. 3. Facies Small. 1 cm1