Volcano-Stratigraphy of La Garrotxa Monogenetic Volcanic Field, Northeastern Spain
La Garrotxa monogenetic volcanic field (GVF) is located in northeastern Iberia and forms part of the Catalan Volcanic Zone (CVZ), which is a province of the Quaternary alkaline volcanism of the European rift system. The GVF corresponds to an area of about 100 km2 located between the cities of Olot and Girona. This basaltic volcanic field comprises more than 50 monogenetic cones including cinder and scoria cones, lava flows, tuff rings, and maars, ranging in age from 0.6 Ma to early Holocene. Strombolian and phreatomagmatic episodes have combined in the construction of most of these cones, which exhibit a wide range of deposits and eruptive sequences. By combining field work, the stratigraphic logging of both water wells and geotechnical drill holes, and the application of shallow geophysical methods, we have been able to establish for the first time a volcano-stratigraphy of the area that identifies the products of each single eruption, their relative stratigraphy, and their areal extent. This volcano-stratigraphy constitutes an essential tool for understanding the evolution of this volcanic field and for volcanic hazard assessment.
KeywordsVolcano-stratigraphy Monogenetic volcanism Garrotxa volcanic field Hazard assessment
- IGC (2007). Carta vulcanològica de la Zona Volcànica de La Garrotxa. Institut Geològic de Catalunya. escala, 1/25 000.Google Scholar
- Martí, J., Planagumà, L., Geyer, A., Canal, E., & Pedrazzi, D. (2011). Complex interaction between Strombolian and phreatomagmatic eruptions in the Quaternary monogenetic volcanism of the Catalan Volcanic Zone (NE of Spain). Journal of Volcanology and Geothermal Research,201(1–4), 178–193.CrossRefGoogle Scholar