Data of Geochemistry, Chapter N., Chemistry of Igneous Rocks; Professional Paper 440-N-1
Washington: United States Government Printing Office, 1975. Sixth Edition. softcover, 11.25" x 9", 37 pages. from the title page, "Tabulation and discussion of chemical analyses of peralkaline, quartz-normative obsidians, the nature of chemical variation within these rocks, and a revised nomenclature." More












