EROSION OF CINDER CONES IN TENERIFE BY GULLY FORMATION, CANARY ISLANDS, SPAIN

Cinder cones were produced by the main basaltic eruptive episodes during the last 1 Ma in Tenerife, Canary Islands. The erosion of cinder cones is a natural process that begins immediately after an eruption. Factors controlling the erosion of monogenetic volcanoes include morphology, age, topographic and emplacement characteristics of the morphoclimatic environment, and local runoff depth. The aim of this paper is to document the evolution of gully erosion on 43 dated cinder cones over time and determine whether age is a critical factor in the degradation level of volcanoes, independent of other factors. The methodology employed is based on geomorphological and morphometric analyses. Only 39.5% of the Tenerife volcanoes have gullies; nevertheless, more than 84.6% of the Pleistocene cones present gullies, compared to only 20% of the Holocene volcanoes. This means that 80% of the Holocene cones have no gullies, whereas only 15.4% of the Pleistocene cones are gully-free. Therefore, the older volcanoes appear to have been more affected by torrential rains. Although the age of a volcano is an essential factor in the degree of erosion, other factors intervene as well. The rate and evolution of these cinder volcanoes depend on a combination of these factors.