Geomorfología, zonas de erosión y sedimentación costera de la Península de Burica, Costa Rica / Geomorphology, erosion and sedimentation in coastal zones of the Burica peninsula

RESUMEN

Resumen Se efectuó una evaluación geomorfológica y de zonas de erosión y sedimentación del sector oeste de la Península, desde punta Banco hasta punta El Mangle, con el fin de determinar aspectos relevantes desde el punto de vista geológico. El estudio se llevo a cabo durante 9 días en enero del 2008, tiempo en el cual, se realizó el estudio geológico, geomorfológico y de zonas de erosión-sedimentación costera, presentándose en este trabajo solamente los resultados relevantes de los últimos dos aspectos. Geomorfológicamente, se reconocen una predominancia de morfologías de origen estructural, y en menor grado de origen marino, fluvial y denudacional. Se definieron cuatro zonas de erosión-sedimentación, zonas de erosión intensa, de erosión moderada a leve, de erosión y sedimentación y zonas de depositación. Los procesos geológicos más importantes son los deslizamientos, la erosión costera y la alta sismicidad del área, factores que deben ser tomados en cuenta para una adecuada planificación rural de la península

ABSTRACT

Abstract The present work describes a geomorpholopic evaluation of the Burica peninsula, during 9 days in January 2008. Coastal geomorphology, erosion and depositional zones were evaluated between punta Banco and punta El Mangle. The most important morphologies found were structural origin morphologies, represented by active tectonic deformation, produced by the Panamá Fracture Zone, and the subduction of the Cocos ridge. The structural origin morphologies identified were, structural-denudational zones which dominate the study area, homocline in the south of the peninsula and structural terraces, that are observed easily between punta El Mangle and La Peña, and in punta Banco. Other morphologies were identified, such as marine, fluvial and denudational morphologies. The marine-origin morphologies include the beach, subdivided in subareas, separated due to the waves dynamic, the cliffs, that dominate the area between La Peña river and punta Banco, and the shore platforms in the area between punta El Mangle and La Peña. The denudational morphology is represented by landslides, which area present mainly in the cliffs. In the other hand, the fluvial origin morphologies, include La Peña, Peñita, Caña Blanca and Coco mouths and the floodplain of La Peña river. Intense erosional, slight to moderate erosional, sedimentational, and erosion and sedimentational zones were identified, having a great importance the coastal erosion, especially observed in the central and south of the peninsula. Considering the results and the interaction of them, the main hazards found are landslides, coastal erosion and the high seismicity of the area, which should be taken into account and studied in detail for a proper planning of the rural development. Rev. Biol. Trop. 63 (Suppl. 1) 407-416. Epub 2015 April 01.