RIVER-DERIVED SLACKWATER SEDIMENTS IN CAVES ALONG CHEAT RIVER, WEST-VIRGINIA

The November 1985 Cheat River flood produced overbank, slackwater depo sits in caves of the Cheat River canyon. The deposits include loamy si lt, loamy sand to very fine sand, and flotsam. Sediments deposited by the November 1985 flood lie within 1 m of the established high water m ark and are good indicators of peak stage. Prehistoric overbank, slack water deposits are present in one cave. These sediments are inferred t o be greater than or equal to 400,000 years old and are, therefore, un related to the modem Cheat River. Overbank slackwater deposits are poo rly preserved in the examined caves, because cave streams actively rem ove sediments and the warm, moist environment of the caves fosters dec ay of woody flotsam. Deposits of the 1985 flood are projected to survi ve at most a few centuries. In contrast, slackwater sediments inferred to be greater than or equal to 400,000 years old are preserved within a cave shielded from significant runoff and biogenic activity.