A new remote-sensing-based volcanic debris avalanche database of Northwest Argentina (Central Andes)

Abstract

 Volcanic debris avalanches are significant landslide events that shape volcanic landscapes globally. This study focuses on creating a comprehensive database of volcanic debris avalanches in Northwest Argentina through remote sensing analysis, leveraging the region’s well-preserved deposits in arid conditions. The database includes morphometric parameters extracted from 12-m spatial resolution TanDEM-X digital elevation models and literature, providing insights into the occurrence and characteristics of these potentially catastrophic events. The methodology involved compiling bibliographic and cartographic data, manual digitization of collapse scars and deposits, and computation of morphometric parameters in a GIS, integrating structural lineaments and hydrothermal alteration zones. The database, which comprises 19 records, features detailed data on scars and deposits, morphometric characteristics, and additional layers for regional lineaments and hydrothermal alteration zones. Statistical analyses reveal correlations between various morphometric parameters, with most avalanche directions aligning perpendicularly to regional tectonic trends and hydrothermal alteration zones identified as significant factors in volcanic instability. The majority of collapses originate from composite volcanoes, with larger collapses linked to dacitic compositions. Collapses have ages between the Upper Miocene and Pliocene. We deem that the database, accessible via the IBIGEO website, will be a valuable tool for researchers and national authorities for geological risk assessment, enhancing the understanding of the spatial and temporal distribution of volcanic debris avalanches in the Central Volcanic Zone of the Andes. Continuous updates and fieldwork are essential to validate and expand the database, addressing gaps and confirming remote observations, thereby contributing to global knowledge on volcanic sector collapses and associated risks.