"The Mt. Alford ring-complex consists of a central boss of porphyritic microdiorite, granophyre and andesite, with a semicircular zone of rhyolitic and trachytic ring-dykes intrusive into upturned sandstones, and cross-cutting non-arcuate dykes of rhyolite, comendite, trachyte, andesite, phonolite and basalt. The petrology and geochemistry of these rocks are discussed and it is concluded that the various rocks have been produced by differentiation of a basic magma."