首页|Detrital gold morphology and recycling around the early Miocene St Bathans paleovalley, Central Otago, New Zealand

Detrital gold morphology and recycling around the early Miocene St Bathans paleovalley, Central Otago, New Zealand

扫码查看
The St Bathans paleovalley developed as a major southwest-draining fluvial system during early Miocene rejuvenation of the Central Otago landscape. Rounded quartz pebbles and detrital gold were recycled from Eocene quartz pebble conglomerates into the headwaters of this Miocene paleodrainage system on the northern margin of the Otago Schist belt. Gold particle morphology is mostly irregular and rough, locally with relict gold crystal shapes, plus a minor component of well-defined flakes. Incremental rounding and surface deformation at the 10 μm scale has occurred through several recycling events in Central Otago, hindering linkage of Miocene and younger placer gold to ultimate basement sources. More intense deformation of the gold, forming thin flakes, occurred in the lower reaches of the Miocene paleodrainage system as gold was transported >100 km to eastern Southland. Hence, the St Bathans paleovalley has been an important source of gold for historic mining in Central Otago and Southland.

PaleodrainagefluvialquartzconglomerategoldplacerflakeSouthland

Marshall Palmer、Dave Craw

展开 >

Geology Department, University of Otago, Dunedin, New Zealand

2025

New Zealand journal of geology and geophysics

New Zealand journal of geology and geophysics

ISSN:0028-8306
年,卷(期):2025.68(2)
  • 33