Kamafugitic Rocks

The core of the problem of carbonate-rich pyroclastic rocks form IAP relates to the question of whether they represent carbonatites or they are fragmented silicate rocks mixed with secondary calcite coming from the wall rocks. The main arguments that have been considered to be in favour 

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Ultrapotassic rocks from Tuscany have a lamproitic composition (see Appendix for nomenclature of potassic rocks). Older lamproites (14 Ma) occur at Sisco, Corsica. Kamafugitic rocks make up a few monogenetic centres in the internal zones of northern-central Apennines (Umbria, Latium, Abruzzi), and have been found at Vulsini and as ejected blocks in pyroclastic deposits at Colli Albani (Federico et al. 1994). Roman-type potassic and ultrapotassic rocks (KS and HKS) form the bulk of magma-... 

Gallo F, Giammetti F, Venturelli G, Vemia L (1984) The kamafugitic rocks from San Venanzo and Cupaello, central Italy. Neues Jahrb Mineral Monatsh 1984 198-210... 

Massive pyroclastic rocks containing kamafugitic juvenile material. 

The main questions concerning the volcanics of the IAP relate to the origin of the kamafugitic lavas at San Venanzo and Cupaello and the nature of carbonate-rich pyroclastic rocks present in several centres. Both issues have been much discussed in the literature, although the debate often has been based on preconceptions rather than on factual evidence. 

The volcanic centres of the LAP consist of pyroclastic deposits and a few lava flows and dyke rocks. Lavas have olivine melilitite and kalsilite meli-litite composition and show an ultrapotassic kamafugitic affinity. Pyroclastic rocks range from melilitite to phonolite. Carbonate-rich pyroclastic rocks are also present. 

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