stripes
West of Lac Aloatra, and close to Amparafaravola, a melilite-bearing flow overlies Precambrian migmatites. Three other occurrences lie in a line to the northeast (Besairie, 1968). The Amparafaravola rock, as described by Prior (1901) and Lacroix (1923), is a melilitite and consists of numerous small phenocrysts of olivine in a matrix of augite, melilite, magnetite and perovskite. Details of the petrography of the three more northeasterly occurrences have not been found.
BESAIRIE, H. 1968. Carte Géologique. Feuille 4. Tamatave. 1:500,000. Service Geologique de Madagasikara, Tananarive.LACROIX, A. 1923. Minéralogie de Madagascar. 3. Lithologie Appendice - Index Geographique. Société d’Éditions Géographiques, Maritimes et Coloniales, Paris. 450 pp.PRIOR, G.T. 1901. Tinguaites from Elfdalen and Rupbachthal: basalts from Madagascar and the Soudan. Mineralogical Magazine, 13: 86-90.