Blackhead is a promontory on the coast of Otago,

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. It lies within the city limits of

Dunedin Dunedin ( ; mi, Ōtepoti) is the second-largest city in the South Island of New Zealand (after Christchurch), and the principal city of the Otago region. Its name comes from , the Scottish Gaelic name for Edinburgh, the capital of Scotland. Th ...

, some southwest of the city centre. The promontory extends some 500 metres into the ocean, and rises to a height of a little over .

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

names for Blackhead include ''Te Wai o Tinarau'' (the waters of Tinarau) and ''Makereatu'' (to leave a seed).GC39JRR Blackhead Basalt Columns
" ''geocaching.com''. Retrieved 7 March 2019. The area of coast to the east of Blackhead is rugged and steep, with many cliff prominences. The tourist attraction of

Tunnel Beach Tunnel Beach is a locality southwest of the city centre of Dunedin, New Zealand. Located just south of St Clair, Tunnel Beach has sea-carved sandstone cliffs, rock arches and caves. Beyond the beauty of the rugged sandstone cliffs, its claim t ...

lies in this area, 3 km from Blackhead. To the west, the coast is more low-lying with beaches. The community of

Waldronville Waldronville is a coastal settlement on the Pacific Ocean coast of the South Island of New Zealand. Established in the 1950s as a commuter settlement, it is located to the southwest of Dunedin city centre, and lies within the city's limits. W ...

is located here, some 1500 metres from Blackhead, close to the mouth of the

Kaikorai Stream The Kaikorai Stream is a short river which runs through the city of Dunedin, in New Zealand's South Island. Course The stream drains the south eastern and eastern slopes of Flagstaff, Kaikorai Hill and the Balmacewen area, flows through Kai ...

. A beach under the shadow of the quarry, Blackhead Beach, is a popular local surfing spot. Geologically, Blackhead formed around a peripheral vent of the

Dunedin Volcano The Dunedin Volcano is an extensively eroded multi-vent shield volcano that was active between 16 and 10 million years ago. It originally extended from the modern city of Dunedin, New Zealand to Aramoana about 25 km away. Extensive erosion has ...

about 10 mya,Blackhead Quarry, Dunedin City
" ''mindat.org''. Retrieved 7 March 2019. the eroded and long-extinct remains of which form the ridge of hills surrounding

Otago Harbour Otago Harbour is the natural harbour of Dunedin, New Zealand, consisting of a long, much-indented stretch of generally navigable water separating the Otago Peninsula from the mainland. They join at its southwest end, from the harbour mouth. I ...

. Notable features of Blackhead relating to its origins include basalt columns, similar to those located at Second Beach, several kilometres to the east. Some of these are readily viewed by the public, such as the series of columns at the western end, which are accessible from Waldronville and Blackhead Beaches. Many of the more spectacular formations, such as the "Roman Baths" and "The Docks" are much harder and more hazardous to access, as they lie on the seaward side of the outcrop. Another feature which is equally difficult to access is Caversham Cavern, one of the largest sea caves on the Otago coast.

Quarry

Blackhead is the site of an active quarry, Blackhead Quarry, which has been operating since the 1950s, and is currently a joint venture between Palmer & Sons and

Fulton Hogan Fulton Hogan is a large infrastructure construction, roadworks and aggregate supplier company in New Zealand, which is also active in wider Australasia. The company was founded by Julius Fulton and Robert Hogan in Dunedin in 1933. In 2013 the c ...

. Around 120,000 tonnes of rock aggregate is produced annually,Blackhead Quarry
," Blackhead Quarries Limited. Retrieved 7 March 2019. consisting mainly of basalt and with small quantities of

natrolite Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula . The type locality is Hohentwiel, Hegau, Germany. It was named natrolite by Martin Heinrich Klapro ...

, phillipsite, calcite,

olivine The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...

chabazite Chabazite ()The New Oxford Dictionary of English (1998) - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.". is a tectosilicate mineral of the zeolite group, clos ...

, and

thomsonite Thomsonite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a ser ...

. This is mainly used for roading chip. The basalt columns are not quarried; they are protected under a

covenant Covenant may refer to: Religion * Covenant (religion), a formal alliance or agreement made by God with a religious community or with humanity in general ** Covenant (biblical), in the Hebrew Bible ** Covenant in Mormonism, a sacred agreement b ...

. During the 1980s, Fulton Hogan proposed to quarry the centre of the headland down to 50 m below sea level and form a boat harbour in the northeast. This was effectively blocked by a conservation group, The Friends of Blackhead, which was formed specifically to oppose the proposals.

References

{{coord, 45, 55, 55, S, 170, 25, 55, E, display=title Headlands of Otago Geography of Dunedin Rock formations of Otago Volcanic plugs of New Zealand

Quarry

See also

References