A volcanic sequence is described from the Golden Cross
Mine, Waihi, New Zealand. The sequence includes seven lithostratigraphic units
comprising flow and pyroclastic units of Coromandel Group andesite and dacite
and overlying Whitianga Group dacite and rhyolite which is intruded by the
Golden Cross dacite porphyry and rhyolite dykes. The sequence is mineralised and
is unconformably overlain by two post-mineral units, the lacustrine Waitekauri
beds and Omahine Subgroup andesite.

Detailed structural analysis
of mine data has identified four deformational events (D 1-D4) and related these
to the gold-silver mineralising events. Faulting was coeval with the
mineralization and directly controlled the development, localisation, style and geometry of
the ore shoots. Mineralization developed in competent lithologies where
dilation occurred during faulting. The Empire Fault is the master shear which
controlled fluid flow. Mineralised veining developed in response to tectonic
pulses occurring at slightly different stages as represented by the underground
Empire vein complex and the open pit vein array. The mineralising events
culminated with the deposition of barren calcite veins. Post-mineral movement along
the Western Boundary fault appears to have offset the
orebody.