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Detailed geochemical and field data for the volcanic sequence and intrusions of the Etendeka Igneous Province are used to construct a stratigraphic framework for petrogenetic interpretation of the evolution of the Etendeka-Parana continental flood volcanic event. Geochemical and petrographic characterization of over 1,000 analyzed samples allows 8 mafic and 17 silicic magma types to be recognized. Both silicic and mafic types can be grouped into high-Ti and low-Ti suites on the basis of elevated Ti relative to other elements. The mafic magmas are: Khumib (high-Ti), Tafelberg, Kuidas, Horingbaai, Huab, Tafelkop, Albin, and Esmeralda (all low-Ti). Amongst the silicic types, the Goboboseb, Springbok, Wereldsend, Grootberg, and Beacon low-Ti quartz latites, and the Nil Desperandum high-Ti latite have been described previously. In addition, the Hoas (low-Ti), Nadas, Sechomib, and Hoarusib, (all high-Ti) latites and the Fria (low-Ti), Sarusas, Ventura, Khoraseb, Naude, and Elliott (all high-Ti) quartz latites are described for the first time here. There is a marked provinciality in the distribution of the high- and low-Ti suites, with the former concentrated in the Northern Etendeka region and the latter dominant in the Southern Etendeka. Stratigraphic distribution of magma types allows two new formations to be defined in the Northern Etendeka – the Khumib Formation of basaltic flows and the Skeleton Coast Formation dominated by silicic sheets. The geochemical provinciality hampers precise correlations between Northern and Southern Etendeka. Available evidence suggests that the lower part of the Awahab Formation in the Southern Etendeka is coeval with the lower part of the Khumib Formation and that the silicic units in the upper part of the Tafelberg Formation probably correlate with the Skeleton Coast Formation. The paucity of Khumib dykes in relation to Tafelberg dykes and their field relationships with regard to the volcanic sequence in the Northern Etendeka suggests that the main Khumib eruptive centers lay further north, consistent with southward thinning of the Khumib basalts. In the Southern Etendeka, the Doros complex is the eruptive center of the plume-derived Tafelkop basalts, which probably built a shield volcano within the regional flood lava field. This work indicates that the Etendeka has a greater variety of both silicic and low-Ti mafic magma types than are known from the SE Parana. Detailed comparisons reveal that all the important silicic types in the Parana have geochemical equivalents in the Etendeka. New correlations are Santa Maria=Fria, Ourinhos=Khoraseb, Guarapuava=Sarusas, thus extending the previously recognized correlations between Southern Etendeka quartz latites and the Caixas do Sul and Anita Garibaldi "rhyolites." These correlations emphasize that very large volume silicic systems develop with pronounced lithospheric rifting in continental flood basalt provinces.

The fumarolic fluids of Vulcano (Aeolian Islands, Italy) consist of a mixture of both deep and shallow components. The final products, the fumarolic gases and the sublimates associated with them, provide information on the complex interactions that occur at depth. As radiogenic isotopes do not undergo fractionation after they are incorporated in a fumarolic gas, they can be used directly to characterize the components that mixed. Lead isotopes are particularly suitable, because seawater, which plays an important part in the formation of the fumarolic fluids of Vulcano, contains only negligible amounts of it (10-12 g/g). Therefore, the lead present in the fumarolic gases (and sublimates) is derived from the magmatic component and a water-rock interaction process. The lead isotope compositions of the lead sulfosalt sublimates collected from the Fossa Crater of Vulcano in 1924, and between 1989 and 1993, are given. The lead isotope ratios of most of the samples are the same within the range of analytical error, regardless of their collection date. The only samples that display slight variations are those collected in 1993. On the whole, the compositional trend of the lead isotopes of the sublimates coincides with that of the latitic-rhyolitic activity of Fossa and differs substantially from that of the pre-Fossa trachy-basaltic activity. The lead composition of the sublimates is very different from that of the Calabrian basement rocks. The data presented here show that the magma presently degassing at Vulcano has the same lead isotopic composition as the products of the recent activity of Fossa, whereas the fumarolic fluid circulation of Vulcano has not involved basement rocks similar to the Calabrian metasediments.

The Etendeka Formation of north-western Namibia consists of a sequence of interbedded quartz latites and tholeiitic basalts and forms part of the Karoo Igneous Province in southern Africa. The age of the Etendeka Formation is approximately 130–135 Ma. The quartz latites make up a significant proportion of the stratigraphic succession (