Golden Bar pit, Macraes Mine, Macraes (Macraes Flat), Waitaki District, Otago Region, South Island, New Zealand
| Latitude & Longitude (WGS84): | 45° 24' 44'' South , 170° 31' 47'' East |
|---|---|
| Latitude & Longitude (decimal): | -45.41237,170.52993 |
| Köppen climate type: | Cfb : Temperate oceanic climate |
Subsidiary pit of the Macraes mine located 6km southeast of main mine area.
The deposit was explored in July 1985 by BP Minerals, December 1994, December 1995, June 1996 to October 1997, and August to September 2002 all by Oceana, before an open pit was subsequently developed.
The deposit was located 400 metres above the Hyde-Macrae Shear Zone Footwall shear within psammite. There are two structural types being concordant lodes, and S curved veins.
The anatomising concordant lodes show as under one metre thick fault altered shear rock, to 15 metres thick quartz rich lode schist. Thin shears dip south or south-east, while flat or north dipping shears are thicker, strongly mineralised, with evidence of extension.
S curved vein packages have a tabular geometry, striking north-east, dipping north-west 25 degrees. Vein dip is steepest where upper and lower concordant structures are greatest. These two major north-east trending shears are 40 metres apart at the surface, but converge at depth. The lower shear contains strong mineralisation, with rock between the shears containing S curved quartz veins, and linking structures. The upper shear is 2-4 metres thick, and the lower shear containing 75% of the mineralisation is 6-12 metres thick.
As of December 31st 2009, measured resources was 0.09 Mt of ore at 1.56 g/t Au, indicated resource of 1.18 Mt of ore at 1.40 g/t Au, and an inferred resource of 4.96 Mt of ore at 1.4 g/t Au for 0.22 Moz Au (0.5 g/t cut-off).
Mineral List
1 valid mineral.
Regional Geology
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
| Triassic - Guadalupian 201.3 - 272.3 Ma ID: 1310198 | Rakaia Terrane Permian-Triassic TZIII schist Age: Phanerozoic (201.3 - 272.3 Ma) Stratigraphic Name: Torlesse Supergroup; Rakaia Terrane Permian-Triassic TZIII schist Description: Pelitic and psammitic schist (TZIII) with minor marble and metachert; local areas of greenschist. Comments: Eastern Province (Rakaia Terrane) Rocks Lithology: Schist, marble, chert, greenschist Reference: Edbrooke, S.W., Heron, D.W., Forsyth, P.J., Jongens, R. (compilers). Geology Map of New Zealand 1:1 000 000. GNS Science Geological Map 2. [12] |
| Olenekian - Kungurian 247.2 - 279.3 Ma ID: 1335176 | Undifferentiated Rakaia Terrane Permian TZIII schist Age: Phanerozoic (247.2 - 279.3 Ma) Stratigraphic Name: Rakaia Terrane; Torlesse Supergroup Description: Schistose quartzofeldspathic sandstone (greywacke) interbedded with mudstone (argillite). Comments: Basement (Eastern Province) metamorphic rocks. Age based on paleontology, mineral dating Lithology: Major:: {schist},Minor:: {metapelite} Reference: Heron, D.W. . Geology Map of New Zealand 1:250 000. GNS Science Geological Map 1. [13] |
Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License
References
