Palaeoproterozoic to Mesoproterozoic Geology of North Queensland

Other Proterozoic Inliers – Coen•Newberry Metamorphic Group– Divided into 3 named units– High-grade metasedimentary and meta-igneous rockssimilar to Yambo Metamorphic Group– Sedimentary protoliths uncertain– Isotopic constraints (Blewett et al., 1998)• Felsic gneisses; ages of 1564±12Ma and 1561±15Maare probably metamorphic ages• Cores in one sample yield an age of 1638±9Ma•Coen Metamorphic Group– Divided into 4 metamorphic units– Schist, gneiss and lesser quartzite; lacks orthogneissand mafic rocks of Newberry and Yambo MetamorphicGroups– Isotopic constraints (OZCHRON)• Feldspathic gneiss has zircons with zoned igneousrims of 1554±4Ma (possibly in situ partial melting)with cores at ~1585, ~1700 and 1770Ma