Recent study of the Kholo Creek quartz diorite, which is considered to be a post-tectonic mass emplaced in the Brisbane metamorphic complex of southeast Queensland, and also of the Samford granodiorite, has led to a hypothesis on their formation. It is thought that the masses have formed at depth following a sequence of gabbro through granodiorite and replacement of plagioclase by potash feldspar, with the amount of xenolithic material dependenton the country rock and the extent of replacement. High-grade regional metamorphism is not involved in the process, as it is mostly on a restricted scale with coalescence of small masses to form larger bodies of homogeneous nature. It is suggested that the hypothesis might be tested in the Loch Doon or Cairnsmore of Carsphairn complexes in Scotland.

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