Not "just a petrographer"; the life and work of Felix Chayes (1916-1993)

Felix Chayes's life and career, largely spent at the Geophysical Laboratory of the Carnegie Institution, Washington, DC, are described. His principal motivation was to improve the reliability of geological interpretation and decision-making through the use of quantitative techniques and the application of statistical methods: e.g., as discussed in his monograph Petrographic Modal Analysis (1956b). He attempted to raise the awareness of the geological community concerning the inherent problems connected with the interpretation of percentaged- and ratio-data, in both petrography and geochemistry, and to develop approaches to their solution (as discussed in his monograph Ratio Correlation, 1971a), although these were never wholly successful. From the mid-1960s onwards, he was deeply involved in the development and application of geochemical databases for igneous petrology (International Geological Correlation Programme--IGCP--Projects 163 and 239). From 1984 he was Chair of the International Union of Geological Sciences (IUGS) Sub-commission on Electronic Databases for Petrology. Emphasis is placed on Chayes's early research as this established the motivation for his statistical approach to petrology.