Inventory and Typology of Landslide-Dammed Lakes of the Cordillera Blanca (Peru) Open image in new window
Despite the fact that landslide-dammed lakes represent less common lake type (n = 23; 2.6% share) in the Cordillera Blanca of Peru, these entities require appropriate scientific attention, because: (i) significantly influence geomorphological processes (erosion-accumulation interactions) at the catchment spatial scale; (ii) act as a natural water reservoirs and balance stream fluctuation on different temporal scales (daily to seasonal); (iii) may represent threat for society (lake outburst flood; LOF). The main objective of this study is to provide inventory of landslide-dammed lakes in the Cordillera Blanca, overview on their typology and discuss their geomorphological significance exemplified by two case studies. Existing, failed and infilled landslide-dammed lakes are simultaneously present in the area of interest. Three sub-types of existing landslide-dammed lakes are distinguished: (i) landslide/rockslide-dammed lakes situated in the main valleys; (ii) debris cone-dammed lakes situated in the main valleys; (iii) lakes situated on landslide bodies irrespective their location. Lakes of sub-types (i) and (ii) reach significant sizes, while lakes of sub-type (iii) do not. The dam formation of lake sub-types (i) and (iii) is usually connected with a single event, while the dams of sub-type (ii) are usually formed by several generations of debris deposition over time. It was shown, that landslide-dammed lakes in the study area are characterized by relatively low mean lake water level elevation (4115 m a.s.l.) and large catchments (in some cases up to 80 km2), compared to other lake types. Lakes of sub-type (ii) are predominantly situated in central glacierized part of the Cordillera Blanca, while lakes of sub-types (i) and (iii) are situated rather in the already deglaciated piedmont areas, reflecting the conditions and mechanisms of dam formation. Two illustrative examples are, further, studied in detail: rockslide-dammed Lake Purhuay close Huari in Marañon River catchment; debris cone-dammed Lake Jatuncocha in Santa Cruz valley, Santa River catchment.
KeywordsLandslide-dammed lake Natural dam Landslide dam Rockslide dam Lake outburst flood Cordillera blanca
The authors would like to thank Autoridad Nacional del Agua, Huaráz, Peru, for the long-term cooperation in high mountain lakes-related research. Grant Agency of Charles University (GAUK project No. 70 613 and GAUK project No. 730 216), Mobility fund of Charles University and the Ministry of Education, Youth and Sports of CR within the framework of the National Sustainability Programme I (NPU I), Grant No. LO1415 are further acknowledged.
- Benozzi E, Mazzari L (2008) Los sitios gemelos de Llamacorral y Awilupaccha. In: Convegno Internazionale di Americanistica. Centro Studi Americanistici “Circolo Amerindiano”, pp 853–858Google Scholar
- Cluff LS (1971) Peru earthquake of May 31, 1970, engineering geology observations. Bull Seismol Soc Am 61:511–533Google Scholar
- Dietrich A, Krautblatter M (2016) Evidence for enhanced debris-flow activity in the Northern Calcareous Alps since the 1980s (Plansee, Austria). Geomorphology, online first, not yet assigned to an issueGoogle Scholar
- Emmer A, Vilímek V, Klimeš J, Cochachin A (2014) Glacier retreat, lakes development and associated natural hazards in Cordillera Blanca, Peru. In: Shan W et al (eds) Landslides in cold regions in the context of climate change. Springer, Cham, pp 231–252Google Scholar
- Haeberli W, Schaub Y, Huggel C (2016) Increasing risks related to landslides from degrading permafrost into new lakes in de-glaciating mountain ranges. Geomorphology, online first, not yet assigned to an issueGoogle Scholar
- Mergili M, Emmer A, Juřicová A, Cochachin A, Fischer J-T, Huggel C, Pudasaini SP (in review) The 2012 multi-lake outburst flood in the Santa Cruz Valley (Cordillera Blanca, Peru): geomorphologic effects and process chain modelling. Water Resour Res, in reviewGoogle Scholar
- Reynolds JM (2003) Development of glacial hazard and risk minimisation protocols in rural environments: methods of glacial hazard assessment and management in the Cordillera Blanca, Peru. Reynolds Geo-Sciences Ltd., FlintshireGoogle Scholar
- UGRH (2015) Consolidado de Actividades Realizadas en el Año 2015 Por la Unidad de Glaciología y Recursos Hídricos. Autoridad Nacional del Agua (ANA), Unidad de Glaciología y Recursos Hídricos (UGRH), Huaráz, 285 pGoogle Scholar
- Zapata ML (1978) Lagunas con obras de seguridad en la Cordillera Blanca. INGEOMIN, Glaciologia y segirudad de lagunas, Huaráz, 9 pGoogle Scholar