“…b) The application of using oxygen isotope thermometry in metamorphic rocks was demonstrated by Clayton and Epstein (1958), and has since been applied by numerous workers, some of the more recent Regional Metamorphism 159 ones are: Fourcade and Javoy (1973), Friedrichsen et al (1973), Black (1974), O'Neil andGhent (1975), Friedrichsen (1974, 1978), Frey et al (1976), and Hoernes and Hoffer (1979).…”