Tecton relationship between the ordovician sedimentary and volcanic successions of the lachlan fold belt, central

Ordovician rocks of the Oberon-Taralga region were deposited in a deep marine environment in the forearc basin outboard of a long-lived Ordovician oceanic island arc and now form basement rocks to the Hill End Zone. The succession consists of two contrasting provinces: the Molong Volcanic Province characterised by mafic-intermediate volcanic and volcaniclastic rocks with associated deepmarine chert and the Quartzose Sedimentary Province composed of monotonous quartz-rich turbidites and chert overlain by graptolitic black shale.