Environmental Monitoring in the Mechara caves, Southeastern Ethiopia: Implications for Speleothem Palaeoclimate Studies
Autor: | Asrat Asfawossen, Baker Andy, Leng Melanie J., Gunn John, Umer Mohammed |
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Jazyk: | angličtina |
Rok vydání: | 2008 |
Předmět: | |
Zdroj: | International Journal of Speleology, Vol 37, Iss 3, Pp 207-220 (2008) |
Druh dokumentu: | article |
ISSN: | 0392-6672 1827-806X |
Popis: | The interpretation of palaeoclimate records in speleothems depends on the understanding of the modern climate of the region, the geology, the hydrology above the caves, and the within-cave climate. Monitoring within-cave climate variability, geochemistry of speleothem-forming drip waters, and associated surface and groundwater, provides a modern baseline for interpretation of speleothem palaeohydrological and palaeoclimate records. Here, we present results of such monitoring of the Mechara caves in southeastern Ethiopia, conducted between 2004 and 2007. Results show nearly constant within-cave climate (temperature and humidity) in all caves, which generally reflects the surface climate. Groundwater and surface water geochemistry is similar across the region (except slight modification by local lithological variations) and modern drip water isotope data fall close to regional Meteoric Water Line, but speleothems further from equilibrium. Holocene and modern speleothems from these caves give high-resolution climate records, implying that the Mechara caves provide a suitable setting for the deposition of annually laminated speleothems that could record surface climate variability in a region where rainfall is sensitive to both the strength of the intertropical convergence zone as well as Indian Monsoon variability. |
Databáze: | Directory of Open Access Journals |
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