CAPE VERDE FIELD TRIP 2015

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In November 23rd 2014 an eruption began inside Chã das Caldeiras in Fogo Island. The eruption was characterised by lava flows and the near village was completely destroyed. This new vent was opened close to the summit cone Pico do Fogo. In fact, Fogo corresponds to a stratovolcano whose morphology is only interrupted by an east-facing caldera-collapse scar that is partially masked by the construction of the new summit cone (Pico do Fogo - 2,829 m). 

The field trip was planned into the area during the period of 23rd of May to the 28th, 2015. The group was composed by members of VeTools project from CSIC group, IESUI group, and FCUL group:

- CSIC group: Joan Martí, Stefania Bartolini, Laura Becerril

- IESUI group: Armann Hoskuldsson, Þorvaldur Þórðarson

- FCUL group: António Brum da Silveira, Ricardo Ramalho

During the trip we have analysed the dynamic of the last eruption and how this new vent has affected the near village. With respect to the lava flow model included in VeTools, the lava flow occurred in Fogo Island was a good example to gain understanding of the changing nature of the lava field growth and to analyse as changes in the topography (as a new road) can affect considerably the lava flow path. All the data collected will help to calibrate the different simulation models for lava flow invasion included in VeTOOLS, thus allowing to conduct a sensitivity analysis of all them and to compare similarities and differences between eruptions. Furthermore, we have had the opportunity to have a meeting with the local Civil Protection to present our project and this is an important task of VeTools as it will facilitate the collaboration between scientists and Civil Proteccion Agencies, sharing the information and experience on the different aspects involved in volcanic hazard assessment and risk management. 



FIELD TRIP:

1 Day - FOGO ISLAND: 

Visit to Chã das Caldeiras, that is the summit caldera of Fogo Island (68 km2). Within this caldera is a large composite cone, Pico de Fogo. 

Cha das Caldeiras is bounded by steep, nearly vertical walls on its north, west, and south sides but is breached on its east side, where lavas have flown to the ocean.

Identification of the 1951 and 1995 eruptions.

2 Day - FOGO ISLAND: 

Observation on how the lava flow of the last eruption inside Chã das Caldeiras, that lasted from the 23rd of November, 2014 to the 7th of February 2015, affected the main road inside the caldera. 

Identification of the main volcano-structural elements of the Caldera wall, such as dykes and faults.

3 Day - FOGO ISLAND: 

Examination of the extension of the basaltic lava flow from the last eruption and its devastation over the small villages that there were within the caldera (Portela and Bangaeira).

Identification of the maximum thicknesses of the front of the lava flows to consider them in the numerical models.

4 Day - FOGO ISLAND:

Visit to the east of Fogo Island. Recognising different basic and felsicoutcroups.Views of the 1951 lava flow from the east of the island.

Identification of the Landslides that have affected the island

5 Day - SANTIAGO ISLAND (Praia): 

Geological trip in Santiago Island observing its main volcanic edifices, landslides, different deposits related to lava flows, pyroclastic flows and pillow lavas and tsunami deposits.

Visit to Cape Verde Civil Protection in the capital of the island, Praia.

© GVB-CSIC 2015