Stratigraphy and eruptive history of Gedemsa caldera volcano, Central Main Ethiopian Rift
Bedassa, Gemechu Ayalew, Dereje Getaneh, Worash Fontijn, Karen Emishaw, Luelseged Melaku, Abate A. Tadesse, Amdemichael Z. Demissie, Zelalem S. Swindle, Andrew L. Chamberlain, Katy J.
Bedassa, Gemechu
Ayalew, Dereje
Getaneh, Worash
Fontijn, Karen
Emishaw, Luelseged
Melaku, Abate A.
Tadesse, Amdemichael Z.
Demissie, Zelalem S.
Swindle, Andrew L.
Chamberlain, Katy J.
Citations
Altmetric:
Other Names
Location
Time Period
Advisors
Original Date
Digitization Date
Issue Date
2024-02
Type
Article
Genre
Keywords
Caldera-forming eruptions,Eruptive history,Gedemsa caldera,Main Ethiopian Rift
Subjects (LCSH)
Citation
Bedassa, G., Ayalew, D., Getaneh, W., Fontijn, K., Emishaw, L., Melaku, A.A., Tadesse, A.Z., Demissie, Z.S., Swindle, A.L., & Chamberlain, K.J. (2024). Stratigraphy and eruptive history of Gedemsa caldera volcano, Central Main Ethiopian Rift. Journal of Volcanology and Geothermal Research, vol. 446, art. no. 107987. https://doi.org/10.1016/j.jvolgeores.2023.107987
Abstract
Gedemsa caldera is a peralkaline volcanic depression located in the Central sector of the Main Ethiopian Rift. An integrated volcanological study of stratigraphic sections was carried out in order to constrain the eruptive history of Gedemsa caldera volcano (GCV), Ethiopia. Textural analyses on plagioclase crystals together with field observations shed light on magma chamber processes feeding the volcanic complex. A multi-vent eruption is ascribed to the pre-caldera volcanic products, as can be seen from the varying caldera wall sequences comprising lavas and pyroclastic deposits. At least three major caldera-forming eruptions are identified producing: 1) a lower ignimbrite, 2) extensive pumice fall and pyroclastic density current deposits, and 3) an upper ignimbrite exposed in different areas of the caldera, indicating a sector collapse. We identified 20 individual pyroclastic deposits found outside and within the caldera that erupted after the climactic caldera collapse. The most recent volcanic activity at Gedemsa is characterized by rhyolitic lava domes and pyroclastic deposits from eruptions through numerous vents aligned with WNW-ESE pre-existing cross-cutting structures. Macrocryst disequilibrium textures such as fine-scale oscillatory zoning (FOZ), sieve textures, glomerocryst, and synneusis indicate that magma reservoir is characterized by repeated magma injection, convection flows, and mixing.
Table of Contents
Description
Click on the DOI link to access this article (may not be free).
Publisher
Elsevier B.V.
Journal
Book Title
Series
Journal of Volcanology and Geothermal Research
vol. 446, art. no. 107987
vol. 446, art. no. 107987
Digital Collection
Finding Aid URL
Use and Reproduction
Archival Collection
PubMed ID
DOI
ISSN
0377-0273