Hillslope evolution by nonlinear creep and landsliding: An experimental study

Citation
Jj. Roering et al., Hillslope evolution by nonlinear creep and landsliding: An experimental study, GEOLOGY, 29(2), 2001, pp. 143-146
Citations number
29
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Earth Sciences
Journal title
GEOLOGY
ISSN journal
0091-7613 → ACNP
Volume
29
Issue
2
Year of publication
2001
Pages
143 - 146
Database
ISI
SICI code
0091-7613(200102)29:2<143:HEBNCA>2.0.ZU;2-H
Abstract
Landscape evolution models are widely used to explore links between tectoni cs, climate, and hillslope morphology, yet mechanisms of hillslope erosion remain poorly understood. Here we use a laboratory hillslope of granular ma terial to experimentally test how creep and landsliding contribute to hills lope erosion. In our experimental hillslope, disturbance-driven sediment tr ansport rates increase nonlinearly with slope due to dilation-driven granul ar creep, and become increasingly episodic at steep slope angles as creep g ives way to periodic landsliding, We use spectral analysis to quantify the variability of sediment flux and estimate the slope-dependent transition fr om creep to landsliding. The power spectrum of sediment flux steepens with hillslope gradient, exhibiting fractal 1/f scaling just below the creep-lan dsliding transition. By evolving the experimental hillslope under fixed bas e-level boundary conditions, we demonstrate how disturbance-driven transpor t generates hillslope convexity, The transient evolution is consistent with numerical predictions derived from a recently proposed nonlinear transport model, as initially steep hillslopes are lowered rapidly by landsliding be fore slopes decay slowly by creep-dominated transport.