Abstract
Chabbi, a Quaternary volcano in the Ethiopian Rift, appears to be unique in having erupted only non-porphyritic pantelleritic obsidians showing a very restricted range in composition. Petrogenetic schemes for deriving these lavas are discussed, and it is suggested that some degree of effective superheating, followed by failure of the magmas to crystallise because of their dryness (and hence high viscosity) can account at least for the absence of phenocrysts.
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Macdonald, R., Gibson, I.L. Pantelleritic obsidians from the volcano Chabbi (Ethiopia). Contr. Mineral. and Petrol. 24, 239–244 (1969). https://doi.org/10.1007/BF00376050
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DOI: https://doi.org/10.1007/BF00376050