Multitemporal ALSM change detection, sediment delivery, and process mapping at an active earthflow

Auteur(s) et Affiliation(s)



Description :
At Mill Gulch in northern California, USA, an active earthflow was surveyed in 2003 and 2007 by airborne laser swath mapping (ALSM), enabling meter-scale quantification of landscape change. The AA. calculate four-year volumetric flux from the earthflow and compare it to long-term catchment average erosion rates from cosmogenic radionuclide inventories from adjacent watersheds. They also present detailed maps of changing features on the earthflow, from which they can derive velocity estimates and infer dominant process. These measurements rely on proper digital elevation model (DEM) generation and a simple surface-matching technique to align the multitemporal data in a manner that eliminates systematic error in either dataset. By making the conservative assumption that these features were the dominant contributor of sediment flux from the entire Mill Gulch drainage basin during this time interval, they calculate a minimum catchment-averaged erosion rate. This study re-affirms the importance of mass wasting processes in the sediment budgets of uplifting weak lithologies.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2012, vol. 37, n°. 3, p. 262-272, nombre de pages : 11, Références bibliographiques : 43 ref.

Date :
2012

Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley