Logo link to homepage

Furnas

Photo of this volcano
  • Portugal
  • Atlantic Ocean
  • Stratovolcano
  • 1630 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 37.77°N
  • 25.32°W

  • 805 m
    2641 ft

  • 382100
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Furnas.

The Global Volcanism Program has no Weekly Reports available for Furnas.

The Global Volcanism Program has no Bulletin Reports available for Furnas.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 9 Holocene eruptive periods.

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1630 Sep 3 1630 Nov 2 Confirmed 5 Historical Observations South end of caldera (Pico da Areia)
1441 ± 2 years Unknown Confirmed 4 Historical Observations Center of caldera (Gaspar), Tephra layer I
1430 ± 100 years Unknown Confirmed 3 Radiocarbon (uncorrected) East caldera floor, Tephra layer H
1170 ± 100 years Unknown Confirmed 4 Radiocarbon (uncorrected) E caldera floor (Lake crater), Tephra layer G
0840 ± 100 years Unknown Confirmed 4 Radiocarbon (uncorrected) Center of caldera (Gaspar), Tephra layer F
0080 ± 100 years Unknown Confirmed 5 Radiocarbon (uncorrected) N floor of younger caldera, Tephra layer C
0360 BCE ± 150 years Unknown Confirmed   Radiocarbon (uncorrected) Tephra layer B
1670 BCE ± 1460 years Unknown Confirmed   Tephrochronology Tephra layer A
4570 BCE (in or before) Unknown Confirmed   Radiocarbon (uncorrected) East rim of caldera (Pico do Canário)
Deformation History

There is no Deformation History data available for Furnas.

Emission History

There is no Emissions History data available for Furnas.

Photo Gallery

The village of Furnas (right) lies in the center of Furnas caldera, whose northern rim forms the ridge in the background. The largest eruption in the last 5,000 years originated at a vent where the village is now located. This Plinian eruption, named Furnas C, occurred about 1,900 years ago. Activity varied between phreatomagmatic and magmatic styles, producing massive fallout of pumice and ash and pyroclastic flows and surges.

Photo by Rick Wunderman, 1997 (Smithsonian Institution).
The low hill covered by fields (left center) is Pico do Gaspar lava dome, surrounded by a low tuff cone. The Lagoa das Furnas lies to the west (right) and the eastern caldera wall can be seen in the left background. The Pico do Gaspar dome has been the site of two eruptions, including in about 1439-1443 CE; descriptions suggest an initial explosive phase producing ash, followed by lava dome formation.

Photo by Rick Wunderman, 1997 (Smithsonian Institution).
Hydrothermal features at Furnas include several fields of fumaroles, hot springs, bubbling pools and mudpits, and the emission of carbon dioxide both at springs and through the soil. Fumarole fields are found on the north shore of Furnas Lake, in the river gorge of the Ribeira Quente, the Ribeira Quente village on the coast outside of the caldera, and in the upper Ribeira dos Tambores. A significant fumarole field, including the hot spring seen here, is located in the main fumarole field, Caldeiras das Furnas, in the village of Furnas.

Photo by Rick Wunderman, 1997 (Smithsonian Institution).
Furnas volcano, at the eastern end of Sao Miguel Island, contains two nested calderas. The southern rim of the younger 6-km-wide caldera is seen here from the north, with Furnas Lake on the right foreground. At least 10 trachytic pumice layers, all erupted during the past 5,000 years, post-date the caldera. The dome with the semi-circle of trees in the center behind the lake is the site of the most recent eruption at Furnas, a sub-Plinian eruption in 1630 CE.

Photo by Rick Wunderman, 1997 (Smithsonian Institution).
GVP Map Holdings

The Global Volcanism Program has no maps available for Furnas.

Smithsonian Sample Collections Database

There are no samples for Furnas in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites