Resumo

LEGORRETA PAULIN, Gabriel et al. Multi-temporal inventory, susceptibility analysis, and volumen estimations for landslides on the SW flank of the Pico de Orizaba volcano, Puebla-Veracruz. Bol. Soc. Geol. Mex [online]. 2014, vol.66, n.2, pp.343-354. ISSN 1405-3322.

This paper provides an overview of the ongoing research from the Institute of Geography, UNAM, that seeks to create a comprehensive methodology for the development of a multi-temporal mapping inventory, susceptibility, and landslide volume estimation by using Geographic Information Systems (GIS). The methodology is established for volcanic terrains where shallow landslides and debris flows are common along the slopes and fluvial systems of volcanoes. The Rio-Chiquito-Barranca del Muerto watershed on the southwestern flank of Pico de Orizaba volcano was selected as a case study to characterize the areas that are prone to slope instability in volcanic terrains. Landslide occurrence was determined through a landslide inventory created from multitemporal aerial photos and fieldwork. In this study, landslide susceptibility was modeled using a cartographic-hydrologic model (Stability Index Mapping - SINMAP) and a statistical model (Multiple Logistic Regression - MLR). Both models were integrated within LOGISNET (developed in Arc Macro Language (AML) using ArcInfo GIS software). The implementation showed that both models have a moderate degree of agreement with the landslide inventory. MLR was preferred for further analysis because of its flexibility to include other variables. Shallow landslides were selected to estimate the volume of material delivered by the landslides to the main stream channel. The area and volume of individual shallow landslides were obtained in the field and through the landslide inventory database to establish an empirical area-volume relationship. The relationship was used to establish a power law in order to estimate the total landslide volume delivered. The results are important in understanding the long-term evolution of the fluvial system on the southwestern flank of Pico de Orizaba, and support the development of a methodology for landslide inventories, landslide susceptibility, and landslide volume estimation in volcanic terrains.

Palavras-chave : Landslides; SIG; susceptibility analysis; Pico de Orizaba volcano.