Fogo Volcano: Geolandscapes and Geothermal Resources - Fully Booked 

Date:  Monday, 2 September, 2 pm to 6 pm

by João Carlos Nunes
PhD Volcanology/ Scientific Director, INOVA Institute/ Assistant Prof., Azores Univ./Eurogeologist, EFG

Fogo Volcano - the youngest of the central volcanoes with caldera on the island of São Miguel - is a polygenetic silicic volcano with a surface area of about 133 km2, the top of which is occupied by a subsidence caldera with a maximum depth of 400 m and a major and minor diameter of 3.4 and 2.2 km respectively. On the flanks of this central volcano there are 77 eruptive centers, as scoria cones, pumice rings, domes and coulées. The outcropping geological formations are mostly made up of trachyte s.l. pyroclastic fall and flow deposits. Over the last 5,000 years, the construction of Fogo's volcanic system has been dominated by explosive eruptions, mostly located inside the caldera.

 

On the Fogo Volcano, a high enthalpy hydrothermal system develops at depth, responsible for hot springs and gaseous emanations, the main foci of which are in the areas of Pico Vermelho, Caldeiras da Ribeira Grande and Caldeira Velha.

Lagoa do Fogo by Paulo H. Silva

 

The deep geothermal system, which contaminate suspended aquifers with thermal fluids rising through permeable fractures, contribute to the existence of hot springs such as Caldeira Velha or Pocinha, or even Ladeira da Velha, in this case interacting with the basal aquifer.

Caldeira Velha by João C. Nunes

 

Currently, the high enthalpy hydrothermal system of the Fogo Volcano is exploited in the Pico Vermelho and Ribeira Grande geothermal power plants, with a total installed capacity of 27.8 MW, which were responsible for producing 153 GWh of electricity in 2022, which corresponds to around 34 per cent of the energy consumed on the island of São Miguel that year.

Geothermal Power Station by Paulo H. Silva

 

General Program (between 2 pm and 6 pm):

• Ribeira Seca old fountain: 1563 A.D. historical eruption
• Pico Vermelho Geothermal Power Plant (with kind permission of EDA Renováveis S.A.)
• Caldeira Velha thermal area
• Fogo volcano caldera
• Caldeiras da Ribeira Grande fumarolic field and termal spa

Registration fee: 50€ and 30€ for students (Limited to 50 participants).