Geologycal analysis from remote sensing sata (Spot and Landsat) in Arequipa area and Colca valley (southern Peru) permits to characterize and to locate three different type of natural hazards: the seismic, volcanic and landslide risks. Seismic risk is associated with numerous faults . The mayor fault system is oriented N070°E to N135°E and affected by a sinistral strike slip-motion. It is associated with minor N055°E opened fractures; these faults may be reactivated by earthquakes. The major fault systems strikes N135°E and forms releasing bends including the N055°E open fractures which may give way to the Quaternary volcanism. At last, the volcanic risk is evidenced by the present-day eruptive process of Nevado Sabancaya and the potential activity of Misti volcano (close to Arequipa). The landslide risk is mainly in the alluvial-lacustrine clays along the steep slopes of the Colca valley.
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