The volcanotectonic evolution of Flores Island, Azores (Portugal)

• Autor(es): Azevedo, J. M. M. ; Ferreira, M. R. Portugal
• Data: 2006
• Identificador Persistente: http://hdl.handle.net/10316/3936
• Origem: Estudo Geral - Universidade de Coimbra
• Assunto(s): volcanic island; volcanic complex and unit; volcanostratigraphy; subsidence and uplift
• Tipo de Documento: Artigo
• Idioma: Inglês

Descrição

From the study and interpretation of the volcanic products and structures of Flores Island, we infer that its volcanic history was dominated by two major periods: (1) proto-insular volcanism, which includes all the submarine and emergent activities; and (2) insular volcanism, consisting exclusively of subaerial eruptions. The first period includes two phases: (1) the oldest (2.2 to 1.5 Ma) of shallow submarine volcanism; (2) the youngest (1.0 to 0.75 Ma) includes emergent volcanism. Throughout the second period, three volcanic stages are recognized: (1) the first one (0.7 to 0.5 Ma) includes the most voluminous volcanism, balanced between effusive and explosive events; (2) an intermediate stage (0.4 to 0.2 Ma) that involves a larger number of small-scale feeder centres, with effusive eruptions prevailing; (3) the third stage is the latest volcanic activity of the Island ([approximate] 0.003 Ma), with strombolian and subsequent phreatic and phreatomagmatic activity centred at four volcanic vents. http://www.sciencedirect.com/science/article/B6VCS-4JXRX3V-2/1/de520353aea9d86efcc9b9a16c855851