Latitude & Longitude (WGS84):	37° 34' 6'' South , 175° 8' 42'' East
Latitude & Longitude (decimal):	-37.56834,175.14514
GeoHash:	G#: rckd38bu9
Köppen climate type:	Cfb : Temperate oceanic climate

The mine was opened in 1954 as an open pit coal mine by State Coal, and closed in 1993. Doug Hood Mining was contracted to conduct earthworks to rehabilitate the site.

Rock units at the mine are basement Mesozoic Hakarimata Formation of siltstone and sandstone. Above this is the Waikato Coal Measures (0-46 metres) with dark grey to grey-brown mudstone, interbedded with brownish black carbonaceous mudstone, coal seams, and siderite concretion. The Glen Afton claystone is above this (0-15 metres) of massive grey-green silty claystone. Then the Pukemiro sandstone (0-6 metres) of glauconitic massive grey green fine sandstone. The Mangakotuku siltstone (0-6 metres) grey-green mudstone. The Whangamarino Formation (0-65 metres) blue-green clayey silt with discontinuous peat bands, wedged shaped silty sand lenses, greywacke gravels in a pumice and quartzose matrix, with muddy sands and muddy gravels. The Kauroa-Hamilton assemblage 0-5 metres of ignimbritic pale reddish yellow and yellow brown sandy silts, and halloysitic silty clays. The Hiwern Formation (0-10 metres) yellow brown to grey brown pumice rich siltstone, sandstone and gravels, interbedded with discontinuous lenses of sandy silt and silty clay. Finally the upper level Tauranga Group (1-15 metres) and Taupo Pumice Alluvials, of swamp and lake sediments or organic rich red clayey siltstone, silty clay, peat, whitish cream highly pumiceous silts, sands and gravels, with common charcoal fragments.

Coal was mined from the Waikato coal measures, a succession up to 65 metres thick, interspersed with the Glen Afton claystone of the Te Kuiti Group. There is the lower Kupakupa coal seam 2-8 metres thick but of variable thickness and dip, and overlying Renown coal seam averaging one metre thick but locally up to 4 metres.

The site is one kilometre south-west of the Huntly town centre. The open pit has now filled with water, and in 2006 was landscaped and turned into a park.

The 1939 era Huntly railway station was moved to the lake shore in 2008, as the future home of the Waikato Coalfields Museum. Ten years later when this was written, the museum is still trying to raise enough money to effect the move.

The pit is now called Lake Puketirini, and is used by a diving school due to its depth, to train divers for under water engineering projects. The lake is 64 metres deep, covering 54 hectares.

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

Mineral List

2 valid minerals.

Rock Types Recorded

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

Holocene - Late Pleistocene 0 - 0.126 Ma ID: 1342778	OIS1 (Holocene) mining waste Age: Pleistocene (0 - 0.126 Ma) Description: Compacted mine waste in backfilled opencast pits and overburden landfill areas. Comments: Holocene human-made deposits. Age based on absolute age calculated from stratigraphic age range Lithology: Major:: {fill} Reference: Heron, D.W. . Geology Map of New Zealand 1:250 000. GNS Science Geological Map 1. [13]
Quaternary 0 - 2.588 Ma ID: 1309116	Late Quaternary alluvium and colluvium Age: Pleistocene (0 - 2.588 Ma) Stratigraphic Name: Pakihi Supergroup Description: Unconsolidated to poorly consolidated mud, sand, gravel and peat. Comments: Zealandia Megasequence Terrestrial and Shallow Marine Sedimentary Rocks (Neogene) Lithology: Mud, sand, gravel, peat 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]
Quaternary 0 - 2.588 Ma ID: 3186104	Cenozoic sedimentary rocks Age: Pleistocene (0 - 2.588 Ma) Lithology: Gravel,sand Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. [154]

Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License

References

External Links