Stratigraphy and Petrography

2 Ankaratrite is a melanocratic variety of nephelinite, rich in olivine phenocrysts and/or xenocrysts, and containing phlogopite. 

The Plio-Peistocene activity is by far the best studied (Beccaluva et al. 1998 Trua et al. 1998). It took place during Lower-Middle Pliocene (4.9 to 3.5 Ma) and Upper Pliocene-Lower Pleistocene (2.4 to 1.5 Ma). The earlier products are principally submarine and are represented by volcano-clastic products, pillow lavas and minor subaerial lava flows. The Upper Pliocene-Lower Pleistocene activity erupted lava in subaerial to shallow marine environments (Di Grande et al. 2002). 

Small (normally up to about 10 cm) xenoliths are found in some Quaternary basanitic and nephelinitic lavas (e.g. Sapienza and Scribano 2000 and references therein). These include both mantle-derived and crustal lithologies. 

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