Dating bedrock gorge incision in the French Western Alps (Ecrins-Pelvoux massif) using cosmogenic 10Be - Archive ouverte HAL Access content directly
Journal Articles Terra Nova Year : 2010

Dating bedrock gorge incision in the French Western Alps (Ecrins-Pelvoux massif) using cosmogenic 10Be

(1) , (1) , (1)
1

Abstract

We report in-situ produced 10Be data from the Gorge du Diable (French Western Alps) to date and quantify bedrock gorge incision into a glacial hanging valley. We sampled gorge sidewalls and the active channel bed to derive both long-term and present-day incision rates. 10Be ages of sidewall profiles reveal rapid incision through the late Holocene (ca 5 ka) at rates ranging from 6.5 to 13 mm yr−1. Present-day incision rates are significantly lower and vary from 0.5 to 3 mm yr−1 within the gorge. Our data imply either delayed initiation of gorge incision after final ice retreat from internal Alpine valleys at ca 12 ka, or post-glacial surface reburial of the gorge. Our results suggest that fluvial incision rates >1 cm yr−1 into crystalline bedrock may be encountered in transient landscape features induced by glacial-interglacial transitions.

Dates and versions

insu-00549845 , version 1 (22-12-2010)

Identifiers

Cite

Pierre G. Valla, Peter van Der Beek, Julien Carcaillet. Dating bedrock gorge incision in the French Western Alps (Ecrins-Pelvoux massif) using cosmogenic 10Be. Terra Nova, 2010, 22, pp.18-25. ⟨10.1111/j.1365-3121.2009.00911.x⟩. ⟨insu-00549845⟩
74 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More