Debris-flow hazard map units from gridded probabilities

Russell H. Campbell; Richard L. Bernknopf

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USGS · 70020332

Debris-flow hazard map units from gridded probabilities

Russell H. Campbell·Richard L. Bernknopf

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Abstract

The common statistical practice of dividing a range of probabilities into equal probability intervals may not result in useful landslide-hazard map units for areas populated by equal-area cells, each of which has a unique probability. Most hazard map areas contain very large numbers of cells having low probability of failure, and as probability increases, the number of cells decreases in a non-linear fashion. Exploration of this distribution suggests that the spatial frequency of expected failures may be used to identify probability intervals that define map units. From a spatial database of gridded probabilities, map units that address the different objectives of land-use planners and emergency response officials can be defined.

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Russell H. Campbell, Richard L. Bernknopf. 1997. Debris-flow hazard map units from gridded probabilities. https://pubs.usgs.gov/publication/70020332

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