Available Weekly Reports
- Volcano Info
- Search Database
- Info & Contacts
There are no activity reports for Gedamsa.
Available Weekly Reports
There are no Weekly Reports available for Gedamsa.
There are no Holocene eruptions known for Gedamsa. If this volcano has had large eruptions prior to 10,000 years ago, information might be found in the LaMEVE (Large Magnitude Explosive Volcanic Eruptions) database, a part of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.
Acocella V, Korme T, Salvini F, Funiciello R, 2003. Elliptic calderas in the Ethiopian Rift: control of pre-existing structures. J Volc Geotherm Res, 119: 189-203.
Berhe S M, 1978. Geological map of the Nazret area. Ethiopian Mapping Agency, 1:250,000.
Di Paola G M, 1972. The Ethiopian Rift Valley (between 7° 00' and 8° 40' lat north). Bull Volc, 36: 517-560.
Peccerillo A, Barberio M R, Yirgu G, Ayalew D, Barbieri M, Wu T W, 2003. Relationships betweem mafic and peralkaline silicic magmatism in continental rift settings: a petrological, geochemical and isotopic study of the Gedemsa volcano, Central Ethiopian Rift. J Petr, 44: 2003-2032.
WoldeGabriel G, 1987. . (pers. comm.).
The Gedamsa caldera is located along the Main Ethiopian Rift east of Lake Koka and SW of the Wonji Sugar Estate Farm. The 7 x 9 km wide caldera (also spelled Gadamsa or Gedemsa) is cut by many NNE-SSW-trending regional faults of the Ethiopian Rift, particularly on the east side of the caldera. The caldera is steep-sided, with 100-200 m high walls whose upper part consists primarily of rhyolitic lava flows, and formed as a result of the eruption of a series of trachytic ignimbrites. Late-Pleistocene to Holocene volcanics form a chain of rhyolitic lava flows and pumice deposits, known as Ittisa, that rises about 200-250 m above the floor of the caldera. A large 1-km-wide crater is located at the eastern part of the chain. A Holocene lava dome or flow is found on the SW flank of the volcano. Regional faults have truncated the volcano, and small basaltic spatter cones have formed inside the caldera rim. Weak fumarolic activity was reported at two locations at Gedamsa.