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Gedemsa Caldera, East Shewa Zone, Oromia Region, Ethiopiai
Regional Level Types
Gedemsa CalderaCaldera
East Shewa ZoneZone
Oromia RegionRegion
EthiopiaCountry

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Latitude & Longitude (WGS84):
8° 22' North , 39° 10' East
Latitude & Longitude (decimal):
8.36667,39.16667
GeoHash:
G#: sc7ze7073
GRN:
N06E28
Type:
Caldera
Köppen climate type:
Cwb : Subtropical highland climate or temperate oceanic climate with dry winters
Nearest Settlements:
PlacePopulationDistance
Wenjī17,120 (2012)15.8km
Nazrēt213,995 (2012)23.2km
Mojo34,547 (2014)25.0km
Huruta12,442 (2012)31.4km
Sirre10,089 (2012)35.3km
Mindat Locality ID:
406690
Long-form identifier:
mindat:1:2:406690:6
GUID (UUID V4):
0
Other/historical names associated with this locality:
Gadamsa


8 km in diameter caldera located immediately east of Lake Koka. It contains 8 pantelleritic and comenditic lava domes a number of which also occur around the caldera.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Aegirine-augite
Formula: (NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Albite var. Oligoclase
Formula: (Na,Ca)[Al(Si,Al)Si2O8]
ⓘ Quartz
Formula: SiO2
ⓘ Sanidine
Formula: K(AlSi3O8)
ⓘ 'Sodic amphibole'

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘAegirine-augite9.DA.20(NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
ⓘSanidine9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘvar. Oligoclase9.FA.35(Na,Ca)[Al(Si,Al)Si2O8]
Unclassified
ⓘ'Sodic amphibole'-

List of minerals for each chemical element

OOxygen
Oⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Oⓘ QuartzSiO2
Oⓘ SanidineK(AlSi3O8)
NaSodium
Naⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
MgMagnesium
Mgⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
AlAluminium
Alⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Alⓘ SanidineK(AlSi3O8)
SiSilicon
Siⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Siⓘ QuartzSiO2
Siⓘ SanidineK(AlSi3O8)
KPotassium
Kⓘ SanidineK(AlSi3O8)
CaCalcium
Caⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Caⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
FeIron
Feⓘ Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6

Other Regions, Features and Areas containing this locality

AfricaContinent
African PlateTectonic Plate

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

Alula, D., Boccaletti, M., Getaneh, A., Mazzuoli, R., Tortorici, L., & Trua, T. (1992). Geological map of the Nazret–Dera region (Main Ethiopian Rift). 1: 50,000 scale, Ministero degli Esteri, Consiglio Nazionale delle Ricerche, S. EL. CA, Firenze.
Woolley, A. R. (2001) Alkaline Rocks and Carbonatites of the World, Part 3: Africa - Alkaline Rocks and Carbonatites of the World. The Geological Society of London.p.84
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