Otago, Clutha River

South Island, New Zealand

Main commodities: Au
Our International
Study Tour Series
The last tour was
OzGold 2019
Our Global Perspective
Series books include:
Click Here
Super Porphyry Cu and Au

Click Here
IOCG Deposits - 70 papers
All available as eBOOKS
Remaining HARD COPIES on
sale. No hard copy book more than  AUD $44.00 (incl. GST)
Big discount all books !!!

The Otago region of the South Island, New Zealand has produced 260 tonnes of gold over the 130 years to 1995, from a range of operations up to and including large scale dredging.

The Central Otago region is drained by a single catchment, the Clutha River system, whose active and Recent stream gravels host major placer deposits of gold.

In tributaries, such as the Manuherikia and Shotover Rivers, eluvial placers are developed over schists containing sparse gold bearing veins.   These schists are overlain by variably auriferous Miocene fluvial sediments with up to 300 micron detrital gold.   The Miocene sediments were eroded during Quaternary warping and uplift of the schists.

Gold in the Miocene sediments has been chemically mobilised on the degraded unconformity to form nuggets up to 2 cm across.   This unconformity has been eroded to produce alluvial fans with coarse alluvial gold, which have been in turn uplifted and eroded to form younger fans.

Subsequent groundwater activity resulted in further nugget rims and an increase in grain size.

For detail consult the reference(s) listed below.

The most recent source geological information used to prepare this summary was dated: 1995.    
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd.   Unauthorised copying, reproduction, storage or dissemination prohibited.

  References & Additional Information
   Selected References:
Craw D, Youngson J H, Koons P O  1999 - Gold dispersal and placer formation in an active oblique collisional mountain belt, Southern Alps, New Zealand: in    Econ. Geol.   v94 pp 605-614
Pitcairn I K, Teagle D A H, Craw D, Olivo G R, Kerrich R and Brewer T S,   2006 - Sources of Metals and Fluids in Orogenic Gold Deposits: Insights from the Otago and Alpine Schists, New Zealand : in    Econ. Geol.   v101 pp 1525-1546
Scanlan, E.J., Scott, J.M., Wilson, V.J., Stirling, C.H., Reid, M.R. and Le Roux, P.J.,   2018 - In Situ 87Sr/86Sr of Scheelite and Calcite Reveals Proximal and Distal Fluid-Rock Interaction During Orogenic W-Au Mineralization, Otago Schist, New Zealand : in    Econ. Geol.   v.113, pp. 1571-1586.
Sibson R H and Scott J  1998 - Stress/fault controls on the containment and release of overpressured fluids: Examples from gold-quartz vein systems in Juneau, Alaska; Victoria, Australia and Otago, New Zealand: in    Ore Geology Reviews   v13 pp 293-306
Youngson J H, Craw D  1999 - Variation in placer style, Gold morphology, and Gold particle behavior down gravel bed-load rivers: an example from the Shotover/Arrow-Kawarau-Clutha River system, Otago, New Zealand: in    Econ. Geol.   v94 pp 615-634
Youngson J H, Craw D  1995 - Evolution of placer gold deposits during regional uplift, central Otago, New Zealand: in    Econ. Geol.   v90 pp 731-745

Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge.   It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published.   While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo takes no responsibility what-so-ever for inaccurate or out of date data, information or interpretations.

Top | Search Again | PGC Home | Terms & Conditions

PGC Logo
Porter GeoConsultancy Pty Ltd
 International Study Tours
     Tour photo albums
 Ore deposit database
 Conferences & publications
PGC Publishing
 Our books  &  bookshop
     Iron oxide copper-gold series
     Super-porphyry series
     Porhyry & Hydrothermal Cu-Au
 Ore deposit literature
 What's new
 Site map