Caracterización geodinámica y dendrocronología como base para la evaluación de procesos geohidrológicos en la cuenca del río Mariño, Abancay (Perú)

• Autores: Villacorta Chambi, Sandra Paula, Rodriguez Morata, Clara, Peña Laureano, Fluquer, Jaimes Salcedo, Fredy, Luza Huillca, Carlos Alberto
• Formato: artículo
• Fecha de Publicación: 2016
• Institución: Instituto Geológico, Minero y Metalúrgico
• Repositorio: INGEMMET-Institucional
• Lenguaje: español
• OAI Identifier: oai:repositorio.ingemmet.gob.pe:20.500.12544/2310
• Enlace del recurso: https://hdl.handle.net/20.500.12544/2310
• Nivel de acceso: acceso abierto
• Materia: Geodinámica; Dendrocronología; Cuencas hidrográficas

[ENG] In the last times, the city of Abancay (located in Apurímac, a region of southern Peru) has experimented a very fast population growth which has led to do an improper land use by occupying geodynamically unstable areas. These areas are prone to suffer geo-hydrological processes often triggered by extreme rainfalls which generate important personal and economic losses in Abancay and its surrounding villages. Regarding this situation, the Geological, Mining and Metallurgical Institute of Peru, together with the University of Geneva (Switzerland), within the framework of the “National Program of Geological Risks”, chose the micro-basin Mariño River to develop geological, hydrogeological, geophysical and dendrochronological studies in order to evaluate future potential geo-hydrological events in the area. First results show that large part of the Mariño River basin is highly susceptible to the occurrence of geo-hydrological events. This susceptibility is mainly related with three factors i) the steep topography, ii) the strong weathering suffer by the bedrock which facilitate the fissure and caves formation and iii) the presence of ancient mass movements often reactivated during the rainy season due to the water infiltration and subsurface flow. Furthermore, from the simulation of the debris flow event occurred in 1951, it can be observed that Tamburco and Abancay districts are especially sensitive to the debris flow occurrence. From this simulation we can extract also that the current structural measures implemented in the Sahuanay stream might not be enough to control a new event similar to the 1951 event. Also preliminary results from the dendrochronological survey shows that P. Glomeratus tress could be useful in order to fill the lack of climatic data in the Abancay area as well as the trees located along the Sahuanay stream in order to get information about the debris flow magnitude occurred in 2012. The ultimate goal of this study is to share these results with the local authorities in order to improve the current plans of risk management.