Resumo

OCHOA-TEJEDA, Verónica  e  PARROT, Jean-François. Automated extraction of landslide traces using a digital terrain model and IKONOS high-resolution satellite images: An example from Sierra Norte de Puebla, Mexico. Rev. mex. cienc. geol [online]. 2007, vol.24, n.3, pp. 354-367. ISSN 1026-8774.

Landslides triggered by torrential rainfalls of October 1999 in the Sierra Norte de Puebla region have been studied in La Soledad sector. The present study is based on IKONOS images and a Digital Terrain Model (DTM). A new algorithm has been developed to define a model M that extracts automatically the landslide traces. A statistical analysis of all the parameters extracted from the images and all the primary attributes derived from the DTM, shows that three indicators are enough to extract these traces, in such a way that the model only corresponds to M(SBI, NDVI, Slope). The extracted items represent more than 75% of the landslides observed in the field. A new algorithm is present for estimating the landslide movement directions. Most landslides present an eastern trend that corresponds to one of the two main directions of the DTM slopes, suggesting that it may respond to the direction of rainfall in relation to the slopes exposition when the phenomenon occurred. The proposed method represents a powerful tool to extract, characterize and define the direction of landslide traces.

Palavras-chave : landslides; automated extraction; shape characteristics; direction; IKONOS; Digital Terrain Model; Sierra Norte de Puebla; Mexico.