Facies in a Devonian‐Carboniferous volcanic fore‐arc succession, Campwyn Volcanics, Mackay district, central Queensland∗

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Abstract
The Middle Devonian to Early Carboniferous Campwyn Volcanics of coastal central Queensland form part of the fore‐arc basin and eastern flank of the volcanic arc of the northern New England Fold Belt. They consist of a complex association of pyroclastic, hyaloclastic and resedimented, texturally immature volcaniclastic facies associated with shallow intrusions, lavas and minor limestone, non‐volcanic siliciclastics and ignimbrite. Primary igneous rocks indicate a predominantly mafic‐intermediate parentage. Mafic to intermediate pyroclastic rocks within the unit formed from both subaerial and ?submarine to emergent strombolian and phreatomagmatic eruptions. Quench‐fragmented hyaloclastite breccias are widespread and abundant. Shallow marine conditions for much of the succession are indicated by fossil assemblages and intercalated limestone and epiclastic sandstone and conglomerate facies. Volcanism and associated intrusions were widely dispersed in the Campwyn depositional basin in both space and time. The minor component of silicic volcanic products is thought to have been less proximal and derived from eruptive centres to the west, inboard of the basin.