Bald Hill, Lyell, Buller District, West Coast Region, South Island, New Zealand
| Latitude & Longitude (WGS84): | 41° 42' 3'' South , 172° 8' 2'' East |
|---|---|
| Latitude & Longitude (decimal): | -41.70087,172.13411 |
| Köppen climate type: | Cfb : Temperate oceanic climate |
Unlike the gold deposits around Lyell, Bald Hill is a molybdenum prospect, approximately 6 kilometres north of the Lyell campground, near the headwaters of Lyell Creek. The prospect was discovered in 1978.
The Bald Hill Granite and Lyell Porphyry form the western margin of the Karamea Granite Batholith, as a suite of foliated, medium grained, muscovite bearing leucogranite, pink microgranite, and biotite-granite. The porphyry is a series of small high level plutons, and cross-cutting dykes, consisting of quartz, granodiorite, quartz diorite, lamphrophyre, and quartz bearing gabbro porphyry.
Molybdenum-copper with minor Bi, is associated with the series of calc-alkaline intrusion porphyry stocks, and dykes. The quartz contains pyrite, molybdenite, chalcopyrite, and bismuthinite, across an area 2.5 kilometres by 0.7 kilometres, in an extensively faulted, steep west dipping, elongated north-south porphyry zone. Significant disseminated sulphide is also found in the surrounding alteration, and Lyell Porphyry. The quartz veins range from 1 to 20 metres thick, forming a stock work.
Mineral List
6 valid minerals.
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
| Mesozoic - Devonian 66 - 419.2 Ma ID: 3188899 | Paleozoic-Mesozoic intrusive rocks Age: Phanerozoic (66 - 419.2 Ma) Lithology: Intrusive igneous rocks 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] |
| Albian - Aptian 100.5 - 125 Ma ID: 1362247 | Rahu Suite biotite or muscovite biotite granite Age: Early Cretaceous (100.5 - 125 Ma) Stratigraphic Name: Rahu Suite Description: Biotite or muscovite-biotite granite. Comments: Basement (Karamea Batholith) igneous rocks. Age based on U-Pb zircon Muir et al 1994, 1997, Waight et al 1997, Tulloch un Lithology: Major:: {granite} Reference: Heron, D.W. . Geology Map of New Zealand 1:250 000. GNS Science Geological Map 1. [13] |
| Early Cretaceous 100.5 - 145 Ma ID: 1311869 | Rahu Suite biotite, granite, granodiorite and tonalite Age: Early Cretaceous (100.5 - 145 Ma) Stratigraphic Name: Rahu Suite Description: Biotite and biotite-muscovite granite, granodiorite and tonalite with quartz diorite and monzodiorite. Comments: Western Province (Tuhua Intrusives) Rocks Lithology: Granite, granodiorite, tonalite, quartz diorite, monzodiorite 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] |
Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License
References
