Lying just to the southwest of 'Ela (No. 14), Gad 'Elu is probably of similar composition but is a much bigger centre. Obsidian flows are particularly abundant. Analyses of comenditic rhyolites, in which generally K2O>Na2O, are in Barberi et al. (1975a).
BARBERI, F., CHEDEVILLE, E., FAURE, H., GIGLIA, G., MARINELLI, G., SANTACROCE, R., TAZIEFF, H. and VARET, J. 1973b. Geology of Northern Afar (Ethiopia) (with a geological map, scale 1:500,000). Revue de Geographie Physique et de Geologie Dynamique, Paris, 15: 443-89.BARBERI, F., SANTACROCE, R. and VARET, J. 1975a. Silicic peralkaline volcanic rocks of the Afar Depression (Ethiopia). Bulletin Volcanologique, 38: 755-90.