Lipari island

New occurrences of selenium were found in rapid succession. J. E. F. Giese of Dorpat, Pleischl of Prague, B. Scholz of Vienna, W. Meissner, J. G. Children, and H. von Meyer all found it in the deposits from various kinds of sulfuric acid. Pleischl detected it in the molybdenite of Schlag-genwald F. Stromeyer, in the volcanic sal ammoniac from the Lipari Islands R. Brandes, in the volcanic sal ammoniac of Lanzarote Island (32). Stromeyer and J. F. Hausmann, DuMenil, J. B. Trommsdorff, J. K. L. Zincken, and Heinrich Rose detected its presence in several minerals (33, 34). 

Occurrence.—Although a relatively rare element, selenium is fairly widespread in nature,1 being frequently found in small quantities both in the combined state in pyrites and sulphide ores 2 and also in the free state in the volcanic sulphur deposits 3 of Italy, Hawaii and the Lipari Islands. In the sulphur deposits the selenium is usually present in the form of an isomorphous mixture with the sulphur. Its occurrence in Swedish pyrites (from Falun) led to the discovery of the element by J. J. Berzelius in 1817,4 during an examination of the deposit formed in the lead chambers of a sulphuric acid plant. Owing to the striking chemical resemblance of the new element to tellurium (see p. 351), Berzelius assigned it the name selenium (Gk. selene, the moon), which, in order to indicate the metalloid nature of the element, is sometimes modified into selenion. 

Fig. 7.7. Simplified geological map of Lipari island. Modified after Tranne et al. (2000) and Calanchi et al. (2002a).

Tennant also investigated the action of fused nitre on gold and platinum, both of which he found to be corroded. He found that magnesian limestone acts prejudicially when used as a fertiliser. He described a method of producing a double distillation with the same heat, and a simple method of preparing potassium by heating caustic potash and iron in a tube and condensing the vapour in a vessel in a cooler part of the tube. He described native boric acid of the Lipari Islands. ... 

Liparite. A term that has been used for rocks of various kinds but, in Europe, it has usually referred to a volcanic rock of the rhyolite type. The name derives from the Lipari Islands, off the N. coast of Sicily, where the rock in question consists chiefly of feldspars and quartz. Italian and Japanese liparites have been used as fluxes in porcelain manufacture. 

Until recently, there was no systematic survey, documentation, and chemical and physical analyses of western Mediterranean obsidian sources. Recently, Tykot completed an extensive survey and documentation of western Mediterranean obsidian sources on the islands of Sardinia, Palmarola, Lipari, and Pantelleria (24-27) for a more detailed discussion. Samples from these sources were analyzed at MURR by INAA and/or XRF and LA-ICP-MS. As expected, INAA (and XRF and LA-ICP-MS) of geologic samples from these sources demonstrated that obsidian from each island had a unique chemical signature(s). In the case of Sardinia, six compositional groups were identified. Because of the analytical cost and semi-destructive nature of INAA, artifacts were analyzed by LA-ICP-MS rather than INAA. XRF would have provided a viable analytical alternative, but many of the artifacts were smaller than the minimum size required for this analysis on a standard laboratory-based stationary XRF instrument... 

This is divided into a western, a central and an eastern sector. The western Aeolian arc (Alicudi, Filicudi, Salina) consists of calc-alkaline rocks with typical island arc signatures. Mafic and intermediate rocks dominate the volcanic sequence, with minor silicic volcanics. The central islands (Vul-cano and Lipari) are dominated by calc-alkaline to shoshonitic mafic to silicic rocks mafic rocks from this sector show isotopic compositions and incompatible trace element ratios similar to the western islands. The eastern arc (Panarea and Stromboli) consists of calc-alkaline to potassic alkaline rocks. Stromboli shows geochemical and isotopic signatures akin to the Neapolitan volcanoes. The Island of Panarea, located between Stromboli and Lipari, has intermediate characteristics between these two volcanoes (Calanchi et al. 2002a). 

Fig. 7.9. Variation diagrams of selected major and trace elements for the islands of Vulcano and Lipari.

Barker DS (1987) Rhyolites contaminated with metapelite and gabbro, Lipari, Aeolian Islands, Italy products of lower crustal fusion or of assimilation plus fractional crystallization Contrib Mineral Petrol 97 460-472... 

Crisci GM, De Rosa R, Esperanfa S, Mazzuoli R, Sonnino M (1991) Temporal evolution of a three component system the Island of Lipari (Aeolian Arc, southern Italy). Bull Volcanol 53 207-221 Cristiani C, Mazzuoli R (2003) Monte Amiata volcanic products and their inclusions. Per Mineral 72 169-181... 

Esperanca S, Crisci GM, De Rosa R, Mazzuoli R (1992) The role of the crust in the magmatic evolution of the Island of Lipari (Aeolian Islands, Italy). Contrib Mineral Petrol 112 450-562... 

Mazzuoli R, Pratesi M (1963) Rilevamento e studio chimico-petrografico delle rocce vulcaniche del Monte Amiata. Atti Soc Tosc Sci Nat A70 355-429 Mazzuoli R, Tortorici L, Ventura G (1995) Oblique rifting in Salina, Lipari and Vulcano Islands (Aeolian Islands, Southern Italy). Terra Nova 7 444-452 Meibom A, Anderson DL (2003) The statistical upper mantle assemblage. Earth Planet Sci Lett 217 123-139... 

Tranne CA, Calanchi N, Lucchi F, Rossi PL (2000) Geological sketch map of Lipari (Aeolian Islands, Italy). Dip Sci Terra, University of Bologna, Italy Tranne CA, Lucchi F, Calanchi N, Rossi PL, Campanella T, Sardella A (2002) Geological map of Filicudi (Aeolian Islands), University of Bologna, LAC Florence... 

The existence of obsidian sources on the Italian islands of Sardinia, Lipari, Palmarola and Pantelleria has been well documented, and early provenance studies... 

For Sardinia, the exploitation of multiple sources was noted prior to the actual identification and characterization of each outcrop. The obsidian sources in the Monte Arci region of Sardinia have now been thoroughly documented and geochemically characterized 18, 19), while the results of recent fieldwork by this author on the other islands are expected to add significantly to earlier studies on Lipari 20), Palmarola 21, 22), and Pantelleria 23, 24). The western Mediterranean sources are briefly described here ... 

Present fractionation of U/Th in the mantle can be studied by comparing ATth with K , values in Table 3. K, ratios are generally higher (Stromboli oceanic islands and ridges), but can be lower (Vulcano, Vulcanello, Lipari Vesuvius Etna) than the corresponding A n, ratios. Fig. 3 is a plot of ( Th/ U) versus FejOj/FeO ratios for some very young volcanics. It should be remembered that ( °Th/ U) = so if the... 

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