Fig. 7

Detrital garnet compositions from Cretaceous sandstones. Classification fields are outlined after Morton et al. (2004): Field A represents high Mg, low Ca garnets which typically derive from granulite facies metasediments; Field B represents variable Ca, low Mg garnets characteristic of greenschist to amphibolite facies metasediments, but may also derive from intermediate-acidic igneous rocks; Field C represents high Ca, high Mg garnets which typically derive from medium to high-grade metabasic rocks