Summit erosion rates deduced from 10Be: Implications for relief production in the central Appalachians
We have measured erosion rates using 10Be from bare-bedrock surfaces exposed at high elevations at Dolly Sods, West Virginia, a classic Appalachian paleoperiglacial plateau. The mean erosion rate from nine samples is 5.7 m/m.y., significantly lower than previously estimated periglacial erosion rates in this region. Measured bare-bedrock erosion rates likely represent the rate at which the highest portions of this broad upland are being lowered. Fluvial incision rates measured in the region over similar time scales are ≥2 times faster, suggesting relief is increasing in this portion of the Appalachians. This observation of increasing relief is inconsistent with prior work suggesting that the central Appalachian landscape is in dynamic equilibrium or currently decreasing in relief. We hypothesize that late Cenozoic climate change has accelerated fluvial incision rates, creating a disequilibrium landscape with growing relief with hillslopes undergoing adjustment to increased fluvial incision rates.