 |
| Titel |
Magnitude and frequency of landslides triggered by a storm event, Loughborough Inlet, British Columbia |
| VerfasserIn |
R. H. Guthrie, S. G. Evans |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1561-8633
|
| Digitales Dokument |
URL |
| Erschienen |
In: Natural Hazards and Earth System Science ; 4, no. 3 ; Nr. 4, no. 3 (2004-08-04), S.475-483 |
| Datensatznummer |
250001698
|
| Publikation (Nr.) |
 copernicus.org/nhess-4-475-2004.pdf |
|
|
|
|
|
| Zusammenfassung |
| One hundred and one landslides were documented across 370km2 following
a rainstorm that swept the British Columbia coastline on 18 November 2001.
Despite the regional nature of the storm, the landslides were spaced close
together, even within the study area. Landslide clustering is attributed to
high intensity storm cells too small to be recorded by the general
hydrometric network. The evidence nicely corroborates previous historical
studies that reached similar conclusions, but against which there was no
modern analog analyzed for coastal British Columbia. Magnitude-cumulative
frequency data plotted well on a power law curve for landslides greater than
10000m2, however, below that size several curves would fit. The
rollover effect, a point where the data is no longer represented by the
power law, therefore occurs at about 1.5 orders of magnitude higher than the
smallest landslide. Additional work on Vancouver Island has provided
evidence for rollovers at similar values. We propose that the rollover is a
manifestation of the physical conditions of landslide occurrence and process
uniformity. The data was fit to a double Pareto distribution and P-P plots
were generated for several data sets to examine the fit of that model. The
double Pareto model describes the bulk of the data well, however, less well
at the tails. For small landslides (<650m2) this may still be a
product of censoring. Landscape denudation from the storm was averaged over
the study area and equal to 2mm of erosion. This is more than an order of
magnitude larger than the annual rate of denudation reported by other
authors for coastal British Columbia, but substantially less than New
Zealand. The number is somewhat affected by the rather arbitrary choice of a
study area boundary. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|