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ankaramite|æŋkəˈreɪmaɪt|
[a. F. ankaramite (Lacroix 1916, in Comptes Rendus CLXIII. 182), f. Ankaramy in Madagascar: see -ite1.]
A melanocratic basaltic rock (see quots.).
1926G. W. Tyrrell Princ. Petrol. vi. 129 Some basaltic types..need to be distinguished from basalts proper... When augite is the predominant mafic mineral the term ankaramite (Ankaramy, Madagascar) is applied. 1933R. A. Daly Igneous Rocks & Depth of Earth xvi. 398 The ankaramites appear to be analogous mixtures of approximately basaltic liquid with concentrated crystals of pyroxene. 1939Geogr. Jrnl. XCIV. 134 Other basic lavas of which ankaramite is one notable type. 1946Nature 3 Aug. 172/1 The commonest rock-type is trachybasalt, accompanied by variations in the ultra-basic direction through olivine-rich trachybasalt and ankaramite to limburgite.
Add: Hence ankaraˈmitic a., of the nature of or containing ankaramite.
1971Nature 23 Apr. 510/2 The lavas comprise a succession of alkali-olivine basalts, basanites, and mugearites; ankaramitic varieties are common. 1975Ibid. 9 Oct. 469/2 All of those rocks are traversed by a swarm of dominantly basaltic and ankaramitic dykes. 1990Jrnl. Petrol. XXXI. 747 The ankaramitic parent magma composition is calculated from the most primitive olivine phenocryst composition. |