GEOMORPHOLOGIC HAZARD AND DISASTERS IN THE SOUTH AMERICAN ANDES

Abstract

Geological-and-tectonic and physiographical features of the South American Pacific coast caused high intensity of morpholitogenesis including disaster-like way of some geomorphologic processes. Their complex, interaction, and intensity of conductive factors increase the risk of disaster. The Andean terrain morphology and rock lithology, precipitation type, and vegetation status are the main drivers that influence the character and high potential intensity of the geomorphologic processes. The enormous hydrometeorological events, frequent seismic shocks, volcanic eruptions, and human impact cause disasters development. A schematic map of disaster and hazardous processes for the Central sector of Andes was compiled. 16 areas with different spectra of the dominant catastrophic processes were identified. The South American Andes extension allows drawing out principles of geomorphologic disasters of these continental marginal mountains in various natural zones - from temporal to subequatorial latitudes, which are characterized by the individual unique heat-moisture rate, which governs both typical and extreme geomorphologic processes. An important feature of the study area is the asymmetric distribution of geomorphologic processes within coastal and inland slopes of the mountain system, as well as latitudinal zoning of this distribution.

Keywords

• geomorphologic hazard and disasters
• south american andes
• intensity of geomorphologic processes
• seismic and volcanic activity
• unbalanced precipitation
• mass movements of debris