CLASSIFICATION OF LAMPROPHYRES, LAMPROITES, KIMBERLITES, AND THE KALSILITIC, MELILITIC, AND LEUCITIC ROCKS

The nomenclature and classification of lamprophyres, lamproites, kimbe rlites and the kalsilitic, melilitic and leucitic rocks are inadequate ly defined. The recommendations of three working groups established by the IUGS Subcommission on the Systematics of Igneous Rocks to resolve aspects of the problem are presented for discussion. New definitions of the above are given, variously in mineralogical and geochemical ter ms, and a revised sequence for the systematic classification of the ro cks is provided, which integrates with the existing IUGS hierarchical system.