Skip to main content
ARS Home » Research » Publications at this Location » Publication #137223
Title: TESTING FOR REACH-SCALE ADJUSTMENTS OF HYDRAULIC VARIABLES TO SOLUBLE AND INSOLUBLE STRATA: BUCKEYE CREEK AND GREENBRIER RIVER, WEST VIRGINIA

Author
item SPRINGER, GREGORY - COLORADO STATE UNIVERSITY
item WOHL, ELLEN - COLORADO STATE UNIVERSITY
item FOSTER, JULIE - WEST VIRGINIA UNIVERSITY
item Boyer, Douglas

Submitted to: Geomorphology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/13/2003
Publication Date: 10/27/2003
Citation: Springer, G.S., Wohl, E.E., Foster, J.A., Boyer, D.G. 2003. Testing for reach-scale adjustments of hydraulic variables to soluble and insoluble strata: Buckeye Creek and Greenbrier River, West Virginia. Geomorphology. 56:201-217.

Interpretive Summary: Understanding of sediment and contaminant transport in mountain region streams flowing across different types of bedrock requires knowledge of watershed landscape forming processes. We studied factors of streambed development and down cutting into soluble and insoluble sedimentary bedrocks in two Appalachian watersheds. Our results showed that stream profiles are relatively constant despite significant changes of bedrock types and streambed down cutting along streams. hese results shed important light on how stream profiles along streams are maintained and integrated. The results will contribute important information for use in models of sediment and contaminant transport in mountain region source water streams.

Technical Abstract: We use quantitative hypothesis tests to explore variations in channel substrate, geomorphic setting, and incision processes against changes in unit stream power (Omega) and shear stress (Tau) in streams incising soluble and insoluble bedrock: Buckeye Creek (14 km2 drainage area) and Greenbrier River (3800 km2), West Virginia. Both streams are incising at = 40 m Ma-1and transport coarse, insoluble sediment. The streams are incising by quarrying, abrasion, and corrosion. Comparisons in thirteen stream reaches reveal that Omega and Tau are 3 to 30 times lower atop soluble versus insoluble bedrock. For constant relative solubility, Omega and Tau are higher in reaches that interact more closely with hillslopes. Mean cross section velocities are highest where evidence of abrasion is prominent on insoluble channel elements. Evidence of quarrying is associated with higher values of Omega and Tau than evidence of corrosion. By inference, the efficiency of corrosion-driven incision on soluble bedrock translates to minimization of mechanical energy expenditure, as represented as Omega and Tau. Incision of insoluble strata presumably requires more mechanical energy expenditure for a similar incision rate. Rapid longitudinal changes in Omega and Tau are associated with similarly rapid declines in particle size in an alluvial reach in Buckeye Creek. The alluvial reach may couple reaches with high and low Omega and Tau by acting as a coarse sediment sink. Depth has adjusted in the Greenbrier River such that changes in Tau are of lesser magnitude. As a result, coarse sediment transport may be continuous across soluble and insoluble bedrock. Overall, variations of Omega and Tau appear to reflect relative substrate solubility, geomorphic setting, and incision processes.