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59-589: The Dunedin volcanic group is a volcanic group that covers over 7,800 km (3,000 sq mi) of Otago in the South Island of New Zealand . It is a recent reclassification of the group previously known as the Waiareka-Deborah volcanic field due to common magma melt ancestries of the Dunedin Volcano with the overlapping alkali basaltic monogenetic volcanic field . Excluded from

118-593: A magma melt hot spot centred near Portobello on the Otago Peninsula that has presumably been accumulating in the last 10 million years since active volcanism ceased. This is because of high surface helium isotope measurements, consistent with a magma pocket. In this region of Otago, there is a metamorphosed belt known as the Otago Schist that formed as part of the Zealandia continent, dated from

177-439: A Labour stronghold. Since 2008 the rest of Otago has been divided between the large rural electorates of Waitaki , which also includes some of the neighbouring Canterbury Region , and Clutha-Southland , which also includes most of the rural part of the neighbouring Southland Region. The Waitaki electorate has traditionally been a National Party stronghold and is currently held by Miles Anderson . The Southland electorate, also

236-657: A National Party stronghold, is currently represented by Joseph Mooney . The earlier Otago electorate existed from 1978 to 2008, when it was split and merged into Waitaki and Clutha-Southland. Two list MPs are based in Dunedin – Michael Woodhouse of the National Party and Rachel Brooking of the Labour Party. One-time Labour Party Deputy Leader David Parker is a former MP for the Otago electorate and currently

295-460: A Presbyterian girls' and boys' school in the city. Unlike other major cities in New Zealand, Dunedin does not have any private intermediate or high schools, as all remaining private intermediate and high schools have been integrated into the state system. 45°52′50″S 170°29′46″E  /  45.88056°S 170.49611°E  / -45.88056; 170.49611 Dorrite Dorrite

354-421: A high incidence of feldspar . Fossils of the late and middle Triassic Warepan and Kaihikuan stages are found in the area. Weather conditions vary enormously across Otago, but can be broken into two broad types: the coastal climate of the coastal regions and the more continental climate of the interior. Coastal regions of Otago are subject to the alternating warm and dry/cool and wet weather patterns common to

413-530: A list MP. Under the Māori electorates system, Otago is also part of the large Te Tai Tonga electorate, which covers the entire South Island and surrounding islands, and is currently held by Te Pāti Māori Party MP Tākuta Ferris . Three of the 18 Ngāi Tahu Rūnanga (councils) are based in the Otago Region. Each one is centred on a coastal marae, namely Ōtākou , Moeraki and Puketeraki at Karitane . There

472-570: A mixed economy. Dunedin is home to manufacturing, publishing and technology-based industries. Rural economies have been reinvigorated in the 1990s and 2000s: in Clutha district, farms have been converted from sheep to more lucrative dairying. Vineyard planting and production remained modest until the middle of the 1990s when the New Zealand wine industry began to expand rapidly. The Central Otago wine region produces wine made from varieties such as

531-483: A small influx at this time. The early and middle years of the twentieth century saw smaller influxes of immigrants from several mainland European countries, most notably the Netherlands . In line with the region's Scottish heritage, Presbyterianism is the largest Christian denomination with 17.1 percent affiliating, while Catholicism is the second-largest denomination with 11.5 percent affiliating. The seat of

590-440: A special character based on a religious or philosophical belief that has been integrated into the state system, but still charge "attendance dues" to cover the building and maintenance of school buildings. These schools are not owned by the government, but otherwise they like state schools cannot charge fees for tuition of domestic students but may request a donation. As Dunedin was founded by Presbyterian Scottish settlers there are

649-622: Is also the Arai Te Uru Marae in Dunedin. The subnational gross domestic product (GDP) of Otago was estimated at NZ$ 14.18 billion in the year to March 2020, 4.38% of New Zealand's national GDP. The regional GDP per capita was estimated at $ 58,353 in the same period. In the year to March 2018, primary industries contributed $ 1.25 billion (9.8%) to the regional GDP, goods-producing industries contributed $ 2.38 billion (18.6%), service industries contributed $ 8.05 billion (63.0%), and taxes and duties contributed $ 1.10 billion (8.6%). Otago has

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708-511: Is better understood by location. The oldest rocks in the group trend towards the west. The Crater, a volcano near Middlemarch, is the high-level vent diatreme facies of an approximately 1.5 km (0.93 mi) wide maar and has an age of 24.8 ± 0.6 Ma for its oldest component. The oldest eruptions of the Dunedin Volcano are likely to have been near Allans Beach on the Otago Peninsula at 16.0 ± 0.4 Ma. The age of Mount Cargill

767-570: Is dominant on Saddle Hill, and phonolitic pyroclastic rock underlies the lava at Scroggs Hill. A historic underground coal mine is reported to have encountered the feeder pipe at Jaffray Hill. Further to the southwest are volcanoes on the western side of Lake Waihola , with at least three vents present. Olivine theralite (nepheline gabbro), clinopyroxenite and peridotite have also been found on this western shore. New Zealand's South Island has many extinct volcanic centres without agreed upon tectonic mechanisms of formation. They extend in age from

826-400: Is marked by an Oligocene carbonate platform that means there was at this time near-total submergence under water. This was later followed by late Oligocene faulting that lifted the area of Otago above sea level. Studies of the volcanic group were previously limited as the ages of the volcanoes were not known well; now the distribution of ages from 25 million to approximately 9 million years ago

885-636: Is measured at 11 Ma. About two-thirds of the eruptions in the entire group took place in the period between 16 and 11 Ma, which includes all of the Dunedin Volcano eruptions as well. The youngest rocks, at Lookout Bluff, may be as recent as 8 Ma, though measurements in this area are considered provisional. The local basaltic monogenetic volcanoes were historically arbitrarily separated from the Dunedin Volcano, as has been determined by subsequent rock analysis. The associated Dunedin volcanic group basalts are likely derived from several subtly different but related isotopic reservoirs. Other long-standing knowledge, such as

944-399: Is part of the reason why Central Otago vineyards are successful in this region. This inland region is one of the driest regions in the country, sheltered from prevailing rain-bearing weather conditions by the high mountains to the west and hills of the south. Summers can be hot, with temperatures often approaching or exceeding 30 degrees Celsius; winters, by contrast, are often bitterly cold –

1003-885: The Cretaceous to the Pliocene and outcrop throughout Otago , Canterbury , and on the Chatham Islands . The largest single eruptive centre in the South Island is the Banks Peninsula Volcano , followed by the Dunedin Volcano. Despite being smaller, the Dunedin volcanic group contains a much larger monogenetic volcanic field of related eruptives than the Banks Peninsula Volcano. These volcanic centres can be dormant for tens of millions of years between eruptions. This implies that

1062-477: The Jurassic through the Cretaceous period . In this belt, Oligocene to Miocene aged volcanic group basement rocks including pumpellyite and actinolite greyschist have erupted through the upper and lower greenschist belts, which are present from Wānaka down to Dunedin. The Otago Schist is overlain by a sedimentary sequence, deposited from Late Cretaceous to Miocene time. The peak of marine transgression

1121-554: The Ngāi Tahu iwi or tribe. Other significant ethnic minorities include Asians, Pacific Islanders, Africans, Latin Americans and Middle Easterners. Otago's early waves of settlement, especially during and immediately after the gold rush of the 1860s, included a substantial minority of southern ( Guangdong ) Chinese settlers, and a smaller but also prominent number of people from Lebanon . The region's Jewish population also experienced

1180-548: The Pinot noir , Chardonnay , Sauvignon blanc , Merlot and Riesling grapes. It has an increasing reputation as New Zealand's leading Pinot noir region. Otago has numerous rural primary schools, several small town primary and secondary schools, and some larger schools in Dunedin . Most are state schools which do not charge tuition, except for international students. Some are state integrated schools, former private schools with

1239-587: The University of Otago , was founded in 1869 as the provincial university in Dunedin. The Province of Southland separated from Otago Province and set up its own Provincial Council at Invercargill in 1861. After difficulties ensued, Otago re-absorbed it in 1870. Its territory is included in the southern region of the old Otago Province which is named after it and is now the territory of the Southland region. The provincial governments were abolished in 1876 when

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1298-576: The Abolition of the Provinces Act came into force on 1 November 1876, and were replaced by other forms of local authority, including counties. Two in Otago were named after the Scottish independence heroes Wallace and Bruce . From this time the national limelight gradually shifted northwards. Otago's flag was chosen from a 2004 competition. It was designed by Gregor Macauly. Beginning in

1357-442: The Dunedin Volcano area at Hoopers Inlet are nepheline syenite plutonic dykes ; however, there are no other plutonic rocks in the group area. Scoria , tuff and basanite overlie Eocene-Oligocene marine sediments in the northwest Yellow Hill-Summer Hills area. Ram Rock, an eroded basanitic pipe to the northeast of this area, is associated with peridotite and pyrometamorphosed Otago Schist xenoliths . The Swinburn area to

1416-902: The Murihiku terrane , an accretion which extends inland through the Hokonui Hills in the Southland region. This itself forms part of a larger system known as the Southland Syncline , which links to similar formations in Nelson (offset by the Alpine Fault ) and even in New Caledonia , 3,500 km (2,200 mi) away. The Catlins ranges are strike ridges composed of Triassic and Jurassic sandstones , mudstones and other related sedimentary rocks, often with

1475-637: The Otago Regional Council is in Dunedin. The council is chaired by Andrew Noone as of July 2021 . There are five territorial authorities in Otago: Otago is represented by four parliamentary electorates . Dunedin and nearby towns are represented by the Dunedin electorate, held by Rachel Brooking , and the Taieri electorate, occupied by Ingrid Leary . Both MPs are members of the Labour Party, and Dunedin has traditionally been

1534-718: The Otago Schist. Kattothyrst, about 1 km (0.62 mi) to its east, is a columnar-jointed basanitic plug. Mount Dasher, about 1.5 km (0.93 mi) to the northwest of Kattothyrst, has basanite lavas with an intervening phonotephrite flow on the northeast side. The Obelisk has a south end of trachybasalt and basalt at the northern end. Just southwest of Dunedin, the Saddle Hill , Jaffray Hill, and Scroggs Hill volcanoes are composed of tuff, basaltic trachyandesite, phonotephrite and basanite lava, emplaced through coal-bearing sediments and Cenozoic mudstone . Basanite

1593-422: The asthenosphere, it would be replaced with hotter rock leading to decompression melting . This theoretically could cause volcanic activity that is locked to the moving lithosphere over many millions of years, as observed in the Dunedin group. Otago Otago ( / ə ˈ t ɑː ɡ oʊ / , / oʊ -, ɒ -/ ; Māori : Ōtākou [ɔːˈtaːkou] ) is a region of New Zealand located in

1652-623: The block mountains impede and dilute the effects of the Nor'wester . The main Central Otago centres, such as Alexandra and Cromwell , are found in the intermontane basins between the block mountains. The schist bedrock influence extends to the eastern part of Otago, where remnant volcanics mark its edge. The remains of the most spectacular of these are the Miocene volcanics centred on Otago Harbour . Elsewhere, basalt outcrops can be found along

1711-605: The broad high valley of the Strath-Taieri in its upper reaches, and the fertile Taieri Plains as it approaches the ocean. Travelling east from the mountains, the Central Otago drylands predominate. These are Canterbury-Otago tussock grasslands dominated by the block mountains, upthrust schist mountains. In contrast to Canterbury, where the Northwest winds blow across the plains without interruption, in Otago

1770-425: The census question. Of those at least 15 years old, 40,458 (19.9%) people had a bachelor's or higher degree, 106,080 (52.2%) had a post-high school certificate or diploma, and 43,974 (21.6%) people exclusively held high school qualifications. The median income was $ 39,100, compared with $ 41,500 nationally. 19,692 people (9.7%) earned over $ 100,000 compared to 12.1% nationally. The employment status of those at least 15

1829-683: The coast and at other sites. Comparatively similar terrain exists in the high plateau land of the Maniototo Plain , which lies to the east of Central Otago, close to the upper reaches of the Taieri River. This area is sparsely populated, but of historical note for its importance during the Otago gold rush of the 1860s. The townships of Ranfurly and Naseby lie in this area. In the southeastern corner of Otago lies The Catlins , an area of rough hill country which geologically forms part of

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1888-462: The country from the southwest. A common variant in this pattern is the centring of a stationary low-pressure zone to the southeast of the country, resulting in long-lasting cool, wet conditions. These have been responsible for several notable historical floods, such as the "hundred year floods" of October 1878 and October 1978. Typically, winters are cool and wet in the extreme south areas and snow can fall and settle to sea level in winter, especially in

1947-447: The country's hydroelectric power. Vineyards and wineries have been developed in the Central Otago wine region . Some parts of the area originally covered by Otago Province are now administered by either Canterbury Regional Council or Southland Regional Council . Like the rest of mainland New Zealand, Otago was first settled by the Māori people . Most of the Māori settlement in Otago

2006-545: The entrance to Otago Harbour . The exact meaning of the term is disputed, with common translations being "isolated village" and "place of red earth", the latter referring to the reddish-ochre clay which is common in the area around Dunedin . "Otago" is also the old name of the European settlement on the harbour, established by the Weller Brothers in 1831, which lies close to Otakou . The upper harbour later became

2065-640: The focus of the Otago Association , an offshoot of the Free Church of Scotland , notable for its adoption of the principle that ordinary people, not the landowner, should choose the ministers. Major centres include Dunedin (the principal city), Oamaru , Balclutha , Alexandra , and the major tourist centres Queenstown and Wānaka . Kaitangata in South Otago is a prominent source of coal . The Waitaki and Clutha rivers provide much of

2124-623: The fossil site of Foulden Maar . The northernmost eruptive centre is at Arnmore, near Ngapara , and the group extends south to near Kaitangata 160 km (99 mi) away. While the easternmost on-land occurrence is at Lookout Bluff in north Otago, seismic data provides evidence of offshore underwater centres. Haughton Hill in the Maniototo is the most northwestern eruptive centre. Over 150 flows, or eruptive centres, are known, and these are mainly of small volume alkaline basanite eruptives. The Dunedin volcanic group shows continued evidence of

2183-491: The group are a group of volcanics of different composition (sub-alkaline basalt to basaltic andesite) and older age (36.4 to 27.6 million years ago) near Oamaru , which have been given the name previously used for the Dunedin group. The older Waiareka-Deborah volcanic field overlaps the new Dunedin volcanic group geographically; though Dunedin Volcano has been well studied from the 1880s since New Zealand's first school of geology

2242-412: The hills and plains of South Otago . More Central and Northern Coastal areas winter is sunnier and drier. Summers, by contrast, tend to be warm and dry, with temperatures often reaching the high 20s and low 30s Celsius. In Central Otago cold frosty winters are succeeded by hot dry summers. Central Otago's climate is the closest approximation to a continental climate anywhere in New Zealand. This climate

2301-521: The interannual Southern oscillation . The Southern Hemisphere storm track produces an irregular short cycle of weather which repeats roughly every week, with three or four days of fine weather followed by three or four days of cooler, damp conditions. Drier conditions are often the result of the northwesterly föhn wind, which dries as it crosses the Southern Alps . Wetter air is the result of approaching low-pressure systems which sweep fronts over

2360-537: The mechanism of formation may be connected to the lithosphere , unlike some other intraplate volcanoes such as the Hawaii island chain , which are rooted in the asthenosphere . One possible mechanism for the creation of these volcanoes is the flaking off of the base of Zealandia's lower lithosphere into the asthenosphere. Zealandia has a thin lithosphere, as it has been extended while rafting away from Australia . If large sections of this already thin lithosphere sank into

2419-561: The north and north-east. In the Pigroot area at the volcano called Trig L, lavas overlie marine sediments and include exotic mantle peridotite and crustal gabbro xenolith-bearing phonolite as the cap. The main eruptive centre in the northwestern area of the Kakanui Range in north Otago is Siberia Hill, with a basanite cap on top of trachybasalt covering a 40 m (130 ft) layer of Eocene to Oligocene sediments above

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2478-645: The occurrence of rhönite , a very rare mineral, with the minerals phonolite and trachyte in the Dunedin Volcano, confused matters until international collaboration with detailed analysis of samples from the whole group area was possible. The central vent at Port Chalmers, which is likely a large diatreme , is filled with breccia in an oval about 1.3 by 2.5 km. The vent contains volcanic clasts of mainly phonolite , with minor proportions of basanite , basaltic-trachyandesite, trachyandesite , syenite , gabbro , pyroxenite , and hornblendite , as well as fragments of Otago Schist and Cenozoic sedimentary rocks. Within

2537-472: The office of provincial Superintendent after the New Zealand provinces were created in 1853. The Otago Province was the whole of New Zealand from the Waitaki River south, including Stewart Island and the sub-Antarctic islands. It included the territory of the later Southland Province and also the much more extensive lands of the modern Southland Region . Initial settlement was concentrated on

2596-540: The population of the Queenstown-Lakes District grew by 60% due to the region's booming tourism industry. Otago had a population of 240,900 in the 2023 New Zealand census , an increase of 15,714 people (7.0%) since the 2018 census , and an increase of 38,430 people (19.0%) since the 2013 census . There were 118,524 males, 121,185 females and 1,188 people of other genders in 94,425 dwellings. 4.3% of people identified as LGBTIQ+ . The median age

2655-691: The population resides in the Dunedin urban area—the region's main city and the country's sixth largest urban area. For historical and geographical reasons, Dunedin is usually regarded as one of New Zealand's four main centres. Unlike other southern centres, Dunedin's population has not declined since the 1970s, largely due to the presence of the University of Otago – and especially its medical school – which attracts students from all over New Zealand and overseas. Other significant urban centres in Otago with populations over 1,000 include: Queenstown , Oamaru , Wānaka , Port Chalmers , Cromwell , Alexandra , Balclutha , Milton and Mosgiel . Between 1996 and 2006,

2714-464: The port and city, then expanded, notably to the south-west, where the fertile Taieri Plains offered good farmland. The 1860s saw rapid commercial expansion after Gabriel Read discovered gold at Gabriel's Gully near Lawrence , and the Otago gold rush ensued. Veterans of goldfields in California and Australia, plus many other fortune-seekers from Europe, North America and China, poured into

2773-524: The region's current official boundaries put much of that river's catchment in Canterbury . The country's fourth-longest river, the Taieri , also has both its source and outflow in Otago, rising from rough hill country and following a broad horseshoe-shaped path, north, then east, and finally southeast, before reaching the Pacific Ocean. Along its course it forms two notable geographic features –

2832-406: The sources of the Clutha / Matau-au, the largest river (by discharge) in New Zealand. The Clutha flows generally to the southeast through Otago and discharges near Balclutha . The river has been used for hydroelectric power generation, with large dams at Clyde and Roxburgh . The traditional northern boundary of the region, the Waitaki River , is also heavily utilised for hydroelectricity, though

2891-423: The south side of State Highway 85 has coarse doleritic textured basaltic volcanics overlying scoria-fall deposits, which in turn overlie Eocene-Oligocene marine sediments. The basalt contains rare xenoliths of peridotite, schist and porcellanitised Cenozoic sediment. North of State Highway 85, thin aphanitic basanitic lavas overlie Miocene sediments. These particular lavas have all been tilted and now mostly dip to

2950-526: The southern half of the South Island administered by the Otago Regional Council . It has an area of approximately 32,000 square kilometres (12,000 sq mi), making it the country's second largest local government region. Its population was 257,200 in June 2024. The name "Otago" is the local southern Māori dialect pronunciation of " Ōtākou ", the name of the Māori village near

3009-532: The then Province of Otago, eroding its Scottish Presbyterian character. Further gold discoveries at Clyde and on the Arrow River around Arrowtown led to a boom, and Otago became for a period the cultural and economic centre of New Zealand. New Zealand's first daily newspaper, the Otago Daily Times , originally edited by Julius Vogel , dates from this period. New Zealand's first university,

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3068-414: The township of Ranfurly in Central Otago holds the New Zealand record for lowest temperature with a reading of −25.6 °C on 18 July 1903. Otago Region covers 31,186.16 km (12,041.04 sq mi). The population is 257,200 as of June 2024, which is approximately 4.8 percent of New Zealand's total population of 5.3 million. The population density is 8.2 people per km . About 41.5 percent of

3127-689: The west, the geography of Otago consists of high alpine mountains. The highest peak in Otago (and highest outside the Aoraki / Mount Cook area) is Mount Aspiring / Tititea , which is on the Main Divide . From the high mountains the rivers discharge into large glacial lakes. In this part of Otago glacial activity – both recent and very old – dominates the landscape, with large U-shaped valleys and rivers which have high sediment loads. River flows also vary dramatically, with large flood flows occurring after heavy rain. Lakes Wakatipu , Wānaka , and Hāwea form

3186-566: Was 38.4 years (compared with 38.1 years nationally). There were 37,749 people (15.7%) aged under 15 years, 53,532 (22.2%) aged 15 to 29, 106,926 (44.4%) aged 30 to 64, and 42,690 (17.7%) aged 65 or older. People could identify as more than one ethnicity. The results were 85.2% European ( Pākehā ); 9.9% Māori ; 3.4% Pasifika ; 8.5% Asian ; 2.2% Middle Eastern, Latin American and African New Zealanders (MELAA); and 2.7% other, which includes people giving their ethnicity as "New Zealander". English

3245-521: Was established at the University of Otago , detailed studies of north-central volcanoes such as the Crater near Middlemarch were done much later, and high-quality composition studies still need to be done to properly classify many volcanics near Oamaru. The volcanic features of the Dunedin group define the city and harbour of Dunedin . Multiple monogenetic basalt volcanoes alter the mainly sedimentary Otago landscape. An eruptive centre provides access to

3304-1131: Was first reported in 1982 by A. Havette in a basalt-limestone contact on Réunion Island off of the coast of Africa. The second report of dorrite was made by Franklin Foit and his associates while examining a paralava from the Powder River Basin , Wyoming in 1987. Analyses determined that this newly found mineral was surprisingly similar to the mineral rhönite, lacking Ti but presenting dominant Fe in its octahedral sites. Other minerals that coexist with this phase are plagioclase , gehlenite - akermanite , magnetite -magnesioferrite-spinel solid solutions, esseneite , nepheline , wollastonite , Ba-rich feldspar , apatite , ulvöspinel , ferroan sahamalite , and secondary barite , and calcite . Dorrite can be found in mineral reactions that relate dorrite + magnetite + clinopyroxene , rhönite + magnetite + olivine + clinopyroxene , and aenigmatite + pyroxene + olivine assemblages in nature. These assemblages favor low pressures and high temperatures. Dorrite

3363-557: Was spoken by 97.5%, Māori language by 1.9%, Samoan by 0.6% and other languages by 11.9%. No language could be spoken by 1.7% (e.g. too young to talk). New Zealand Sign Language was known by 0.5%. The percentage of people born overseas was 23.8, compared with 28.8% nationally. Religious affiliations were 28.4% Christian , 1.0% Hindu , 0.8% Islam , 0.2% Māori religious beliefs , 0.7% Buddhist , 0.5% New Age , 0.1% Jewish , and 1.4% other religions. People who answered that they had no religion were 60.3%, and 6.6% of people did not answer

3422-413: Was that 101,514 (50.0%) people were employed full-time, 31,086 (15.3%) were part-time, and 4,848 (2.4%) were unemployed. The majority of the population of European lineage is of Scottish stock—the descendants of early Scottish settlers from the early 19th century. Other well-represented European groups include those of English, Irish, and Dutch descent. A large proportion of the Māori population are from

3481-776: Was upon the coast and centred around the Otago Peninsula . The Otago settlement, an outgrowth of the Free Church of Scotland , was founded in March 1848 with the arrival of the first two immigrant ships from Greenock on the Firth of Clyde — the John Wickliffe and the Philip Laing . Captain William Cargill , a veteran of the Peninsular War , was the secular leader. Otago citizens subsequently elected him to

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