Quaternary warping and uplift of antiformal schist ranges in Central Otago, New Zealand, has resulted in recycling of
alluvial gold from widespread, generally weakly auriferous, Miocene fluvial gravels that unconformably overlie the schist,
into aprons of fan sediments along the range margins. Basement erosion during uplift has been limited and so gold input
from sparse gold-bearing quartz veins in the schist has been relatively minor. In an eluvial cycle on the slopes of the ranges, chemical remobilization of gold occurs during oxidation and erosion of the
Miocene sediments. The typically fine-grained (300-400m) gold undergoes chemical modification and grain size
enhancement of up to two orders of magnitude, and much of it is redeposited in a large number of relatively small alluvial
fans along the range margins. Groundwater mobility within the fans results in minor additional gold mobility and grain size
Enhancement.