Ocean-floor volcanism in the Lachlan Fold Belt: new evidence from the Wyalong area, New South Wales

Updated: 2018-04-20

Geochemical data indicate that a recently recognised sequence of Ordovician volcanic rocks (the Narragudgil Volcanics) south of Wyalong (NSW) accumulated in an oceanic environment, either in a mid-ocean ridge (MORB) or back-arc basin (BAB) setting. These volcanics occur in the same package of highly magnetic rocks with a complex magnetic signature as the Gidginbung Volcanics, host to the Temora gold deposit. They were previously considered to be part of the Gidginbung Volcanics, although Warren et al. (1995: Cootamundra 1:250 000 Sheet Explanatory Notes, Geological Survey of New South Wales) noted the presence of rocks in this area as having "...affinities to the older Jindalee Group with which they may be correlatable.