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Caldeira Volcano, Horta, Faial, Azores, Portugali
Regional Level Types
Caldeira VolcanoVolcano
HortaMunicipality
FaialIsland
AzoresAutonomous Region
PortugalCountry

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PhotosMapsSearch
06725980017781782874580.jpg
Caldeira Volcano

Caldeira Volcano, Horta, Faial, Azores, Portugal
06725980017781782874580.jpg
Caldeira Volcano

Caldeira Volcano, Horta, Faial, Azores, Portugal
00015720017781782886380.jpg
Caldeira Volcano

Caldeira Volcano, Horta, Faial, Azores, Portugal
Latitude & Longitude (WGS84):
38° 35' 17'' North , 28° 42' 57'' West
Latitude & Longitude (decimal):
38.58808,-28.71609
GRN:
N26W17
Type:
Volcano
Köppen climate type:
Cfb : Temperate oceanic climate
Nearest Settlements:
PlacePopulationDistance
Cedros907 (2018)5.6km
Castelo Branco1,309 (2018)7.3km
Ribeira Grande5,198 (2018)8.1km
Horta6,572 (2018)9.6km
Angústias2,418 (2018)10.1km
Mindat Locality ID:
405254
Long-form identifier:
mindat:1:2:405254:1
GUID (UUID V4):
0


Earlier activity produced lava flows, later activity is mostly represented by pumice fallout deposits.

With a diameter of about 2 km, this caldera formed after numerous eruptions, interspersed with periods of quiescence, over the past 400,000 years.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


8 valid minerals.

Rock Types Recorded


Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Aegirine
Formula: NaFe3+Si2O6
ⓘ Aegirine-augite
Formula: (NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Albite var. Anorthoclase
Formula: (Na,K)AlSi3O8
ⓘ Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ 'Hypersthene'
Formula: (Mg,Fe)SiO3
ⓘ Kaersutite
Formula: NaCa2(Mg3AlTi4+)(Si6Al2)O22O2
ⓘ Nepheline
Formula: Na3K(Al4Si4O16)
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Quartz
Formula: SiO2
ⓘ Sanidine
Formula: K(AlSi3O8)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘAugite9.DA.15(CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘAegirine-augite9.DA.20(NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
ⓘAegirine9.DA.25NaFe3+Si2O6
ⓘKaersutite9.DE.15NaCa2(Mg3AlTi4+)(Si6Al2)O22O2
ⓘNepheline9.FA.05Na3K(Al4Si4O16)
ⓘSanidine9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘvar. Anorthoclase9.FA.35(Na,K)AlSi3O8
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Hypersthene'-(Mg,Fe)SiO3
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
OOxygen
Oⓘ AegirineNaFe3+Si2O6
Oⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Albite var. Anorthoclase(Na,K)AlSi3O8
Oⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ Hypersthene(Mg,Fe)SiO3
Oⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
Oⓘ NephelineNa3K(Al4Si4O16)
Oⓘ QuartzSiO2
Oⓘ SanidineK(AlSi3O8)
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ AegirineNaFe3+Si2O6
Naⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Albite var. Anorthoclase(Na,K)AlSi3O8
Naⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
Naⓘ NephelineNa3K(Al4Si4O16)
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Mgⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ Hypersthene(Mg,Fe)SiO3
Mgⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
AlAluminium
Alⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Albite var. Anorthoclase(Na,K)AlSi3O8
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
Alⓘ NephelineNa3K(Al4Si4O16)
Alⓘ SanidineK(AlSi3O8)
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Siⓘ AegirineNaFe3+Si2O6
Siⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Albite var. Anorthoclase(Na,K)AlSi3O8
Siⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ Hypersthene(Mg,Fe)SiO3
Siⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
Siⓘ NephelineNa3K(Al4Si4O16)
Siⓘ QuartzSiO2
Siⓘ SanidineK(AlSi3O8)
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
KPotassium
Kⓘ Albite var. Anorthoclase(Na,K)AlSi3O8
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ NephelineNa3K(Al4Si4O16)
Kⓘ SanidineK(AlSi3O8)
CaCalcium
Caⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Caⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Caⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ KaersutiteNaCa2(Mg3AlTi4+)(Si6Al2)O22O2
FeIron
Feⓘ AegirineNaFe3+Si2O6
Feⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Feⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ Hypersthene(Mg,Fe)SiO3

Other Regions, Features and Areas containing this locality

African PlateTectonic Plate
Atlantic Ocean
EuropeContinent

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Zanon, V., Kueppers, U., Pacheco, J. M., & Cruz, I. (2013). Volcanism from fissure zones and the Caldeira central volcano of Faial Island, Azores archipelago: geochemical processes in multiple feeding systems. Geological Magazine, 150(3), 536-555. doi.org/10.1017/S0016756812000702
Larrea, P., França, Z., Widom, E., & Lago, M. (2018). Petrology of the Azores Islands. In Volcanoes of the Azores (pp. 197-249). Springer, Berlin, Heidelberg.
Woolley, Alan R. (2019) Alkaline Rocks and Carbonatites of the World. Part 4: Antarctica, Asia and Europe (excluding the former USSR), Australasia and Oceanic Islands. The Geological Society of London. doi:10.1144/mpar4
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