Misplaced Pages

#974025

148-572: The Cromwell Gorge is a steep gorge cut by the former Clutha River ( Māori : Mata-Au ) in the Central Otago region of New Zealand's South Island . It winds 19 km (12 mi) between the Dunstan and Cairnmuir Mountains, linking the townships of Cromwell and Clyde . It is one of three substantial river gorges in Central Otago , the others being the Kawarau Gorge to the west of Cromwell, and

296-530: A taua for whom he had prepared a trap. Historically, Kāi Tahu travelled upstream the Clutha River to fish for eels and hunt waterfowl . Kāi Tahu used to travel in to the interior of the South Island almost every year and had campsites and burial sites along the Clutha River and its nearby lakes. The mouth of Mata-au was heavily populated, with many permanent and temporary Kāi Tahu settlements throughout

444-470: A microclimate that meant that orchardists would not need to burn smoke pots to save the fruit from spring frosts and importantly, the crop ripened ahead of the apricots grown in orchards in (e.g.) Earnscleugh or Cromwell. This made the Cromwell Gorge unique in the region and subsequently it produced some of New Zealand's best fruit. The Annan's were one of the first families to establish an orchard at

592-700: A broad trend of very gradual cooling known as Neoglaciation , which lasted from the end of the HCO to before the Industrial Revolution . From the 10th-14th century, the climate was similar to that of modern times during a period known as the Mediaeval Warm Period (MWP), also known as the Mediaeval Climatic Optimum (MCO). It was found that the warming that is taking place in current years is both more frequent and more spatially homogeneous than what

740-455: A discharging mean flow of 614 cubic metres per second (21,700 cu ft/s). The Clutha River played a prominent role in both the Māori and European history of the area. Rivers and valleys were the main transport system used by local Māori to access the interior of the South Island. The 1860s Otago gold rush resulted in the production of approximately 240 tonnes of gold, which was found in

888-503: A few trees from what was Jackson's orchard ( 45°05′07″N 169°15′49″E  /  45.0852°N 169.2637°E  / 45.0852; 169.2637 ) still remain at the edge the lake. The reservoir behind the Clyde dam flooded a total of 2,300 ha (5,700 acres) of productive land, including twelve large orchards on the river terraces along both sides of the Cromwell Gorge, five orchards at Lowburn, and fertile farmlands on both sides of

1036-614: A gold rush to what would become known as Hartley's Beach . Hartley and Reilly, in divulging the location of their rich finds (approximately one mile downstream of the Clutha River's confluence with the Kawarau River), were rewarded with £2000 from the Otago Provincial Government. On 23 September 1862 the Dunstan goldfield was proclaimed, the selection of this name in preference to Hartley's being largely in deference to Reilly, who

1184-572: A healthy orchard and was mentioned in the Evening Star as part of an exhibition of fruit from Central Otago. The last orchardist to leave the Cromwell Gorge ahead of inundation by Lake Dunstan, was Kevin Jackson, who had run an orchard in the gorge from 1969–1989. Jackson and many others whose livelihoods would be irrevocably damaged by the filling of the dam challenged the Government, but to no avail. Only

1332-593: A larger effect on the mid-to-low latitudes and mid-to-high latitudes after ~5600 B.P. Human activity through land use changes already by the Mesolithic had major ecological impacts; it was an important influence on Holocene climatic changes, and is believed to be why the Holocene is an atypical interglacial that has not experienced significant cooling over its course. From the start of the Industrial Revolution onwards, large-scale anthropogenic greenhouse gas emissions caused

1480-458: A low dam at Clyde that would minimise the size of the reservoir. The Labour Government in 1975 selected Scheme H but a change in government to Robert Muldoon's National Party in 1976 reversed this decision, opting instead for Scheme F, a high dam to be built at Clyde which would impact the Cromwell Gorge, Cromwell, the Kawerau Arm and Lowburn . The impact on existing activities from any scheme

1628-641: A man who had run away from the Kaikōura ranges. Chalmers made his trip into Central Otago's interior when no roads or tracks existed, hoping to retrace the steps that his guide, Reko, had made from the Waitaki some twenty years earlier. The trek from the Mataura River in Southland to Waitaki was some 400 km (250 mi) distance, climbing mountain passes in excess of 1,000 m (3,300 ft) – something Chalmers

SECTION 10

#1732848604975

1776-552: A marine transgression occurred in southeastern Africa; in the Lake Lungué basin, this sea level highstand occurred from 740 to 910 AD, or from 1,210 to 1,040 BP, as evidenced by the lake's connection to the Indian Ocean at this time. This transgression was followed by a period of transition that lasted until 590 BP, when the region experienced significant aridification and began to be extensively used by humans for livestock herding. In

1924-589: A mean discharge of approximately 500 m (18,000 cu ft), a catchment area of around 22,000 km (8,500 sq mi), and a length of about 340 km (210 mi), which makes it one of the longest rivers in New Zealand. The major tributaries include the Arrow River , Cardrona River , Lindis River , Manuherikia River , Teviot River , Pomahaka River , and the Waitāhuna River . Towns near

2072-643: A more sustainable sedentary lifestyle . This form of lifestyle change allowed humans to develop towns and villages in centralized locations, which gave rise to the world known today. It is believed that the domestication of plants and animals began in the early part of the Holocene in the tropical areas of the planet. Because these areas had warm, moist temperatures, the climate was perfect for effective farming. Culture development and human population change, specifically in South America, has also been linked to spikes in hydroclimate resulting in climate variability in

2220-567: A much wetter climate from 11,400 to 11,100 BP due to intensification of the ISM. Over the Early Holocene, the region was very wet, but during the Middle Holocene from 6,200 to 3,900 BP, aridification occurred, with the subsequent Late Holocene being relatively arid as a whole. Coastal southwestern India experienced a stronger ISM from 9,690 to 7,560 BP, during the HCO. From 3,510 to 2,550 BP, during

2368-520: A near unanimous vote, the rejection of the working group's Anthropocene Epoch proposal for inclusion in the Geologic Time Scale. The Holocene is a geologic epoch that follows directly after the Pleistocene . Continental motions due to plate tectonics are less than a kilometre over a span of only 10,000 years. However, ice melt caused world sea levels to rise about 35 m (115 ft) in

2516-596: A negative excursion in the δ O record lasting 400 years, is the most prominent climatic event occurring in the Holocene Epoch, and may have marked a resurgence of ice cover. It has been suggested that this event was caused by the final drainage of Lake Agassiz , which had been confined by the glaciers, disrupting the thermohaline circulation of the Atlantic . This disruption was the result of an ice dam over Hudson Bay collapsing sending cold lake Agassiz water into

2664-522: A number of 32 huts and 79 rock shelters present in the area. Around 100 dredges have operated at various times during the area's history in the river bed and nearby gravels, including the present-day gorge to the east of the Old Man Range . The Clutha River and its tributary Kawarau transported alluvial gold across a distance of 200 km (120 mi) in river bed load. A Middle Pleistocene -age ancestral Clutha River delivered detrital gold across

2812-496: A result, this caused significant damage downstream. Over 21,000 livestock were lost when waters flooded over 12,000 h (43,000 ks). The Balclutha Bridge collapsed on 13 October. The 1978 flood breached the banks of rivers from the Ōreti in the south to the Tokomairaro . Over 12,000 hectares (30,000 acres) of land was inundated, with the loss of over 21,000 livestock. Towns and areas affected stretched from Makarora in

2960-467: A role. Drangajökull, Iceland's northernmost glacier, melted shortly after 9,200 BP. In Northern Germany , the Middle Holocene saw a drastic increase in the amount of raised bogs, most likely related to sea level rise. Although human activity affected geomorphology and landscape evolution in Northern Germany throughout the Holocene, it only became a dominant influence in the last four centuries. In

3108-645: A well-defined pervasive schistosity , with shallow dips defining the broad regional-scale warps in schistosity caused during Miocene deformation (the Kaikoura orogeny ). The warped geometries are antiformal over mountain ranges and synformal under the intervening basins. Associated reverse faulting (the Otago fault system ) along the south-eastern flanks of many Central Otago mountain ranges (i.e. Taieri Ridge , Lammermoor Range , Rock and Pillar Range , Rough Ridge , Raggedy Range , Dunstan Mountains, Pisa Range ) gives rise to

SECTION 20

#1732848604975

3256-551: Is an order of magnitude lower than on the Main Divide . The mean flow of the Clutha is around 614 cubic metres per second (21,700 cu ft/s), comparable to many much larger rivers. This heavy flow, combined with the relatively small size of the river in global terms, makes the Clutha notoriously fast-flowing. It is often listed as one of the world's most swiftly flowing rivers, alongside Australia's Macleay and Fitzroy Rivers ,

3404-528: Is designed to accommodate up to 2 m (6.6 ft) of lateral fault movement and 1 m (3.3 ft) of vertical movement. Geologists at the time considered there was a low to very-low possibility of movement along the Dunstan Fault upstream of the dam in the event of a major earthquake; such a movement could lead to up to 200 mm (7.9 in) of relative movement on the River Channel Fault at

3552-454: Is most-often attributed to Jean Desire Feraud , a French goldminer and orchardist who was part of the Otago gold rush . There is evidence of native plant regeneration (such as kōwhai ) in areas where conservation has been put in place, though its reestablishment in the Cromwell Gorge is not nearly as extensive as the nearby Roxburgh Gorge . Forests of kōwhai ( Sophora microphylla ) have recently been postulated to have also been present in

3700-633: Is the second longest river in New Zealand and the longest in the South Island . It flows south-southeast 338 kilometres (210 mi) through Central and South Otago from Lake Wānaka in the Southern Alps to the Pacific Ocean , 75 kilometres (47 mi) south west of Dunedin . Gold is in abundance in the Clutha River and its surrounding areas. It is the highest volume river in New Zealand, and has

3848-498: Is used for all the seven epochs of the Cenozoic Era. The International Commission on Stratigraphy has defined the Holocene as starting approximately 11,700 years before 2000 CE (11,650 cal years BP , or 9,700 BCE). The Subcommission on Quaternary Stratigraphy (SQS) regards the term 'recent' as an incorrect way of referring to the Holocene, preferring the term 'modern' instead to describe current processes. It also observes that

3996-637: The Amazon and Atrato Rivers in South America, and the Teesta River in the Himalayas. The highest recorded flow on the Clutha was during heavy storms in 1978, peaking at 4,581 cubic metres per second (161,800 cu ft/s). A 2022 report of the river by the National Institute of Water and Atmospheric Research (NIWA) indicated a result of 12 species of native fish, and 2 species from its tributaries, with

4144-658: The French Alps , geochemistry and lithium isotope signatures in lake sediments have suggested gradual soil formation from the Last Glacial Period to the Holocene climatic optimum , and this soil development was altered by the settlement of human societies. Early anthropogenic activities such as deforestation and agriculture reinforced soil erosion, which peaked in the Middle Ages at an unprecedented level, marking human forcing as

4292-536: The International Commission on Stratigraphy (ICS) had a working group to determine whether it should be. In May 2019, members of the working group voted in favour of recognizing the Anthropocene as formal chrono-stratigraphic unit, with stratigraphic signals around the mid-twentieth century CE as its base. The exact criteria was still to be determined, after which the recommendation also had to be approved by

4440-603: The Intertropical Convergence Zone (ITCZ) produced increased monsoon rainfall over North Africa. The lush vegetation of the Sahara brought an increase in pastoralism . The AHP ended around 5,500 BP, after which the Sahara began to dry and become the desert it is today. A stronger East African Monsoon during the Middle Holocene increased precipitation in East Africa and raised lake levels. Around 800 AD, or 1,150 BP,

4588-717: The Kalahari Desert , Holocene climate was overall very stable and environmental change was of low amplitude. Relatively cool conditions have prevailed since 4,000 BP. In the Middle East, the Holocene brought a warmer and wetter climate, in contrast to the preceding cold, dry Younger Dryas . The Early Holocene saw the advent and spread of agriculture in the Fertile Crescent — sheep , goat , cattle , and later pig were domesticated, as well as cereals, like wheat and barley , and legumes —which would later disperse into much of

Cromwell Gorge - Misplaced Pages Continue

4736-603: The Lindis Pass was the usual route for early Māori to access their summer camps at Lake Hāwea and Lake Wānaka , there is sufficient evidence the Cromwell Gorge was used as an important thoroughfare. Early Māori archaeological sites are concentrated through the gorge, particularly on the true left of the former Clutha River, and include small Moa hunter camps with associated Moa bones. Four sites have been identified at Rockfall I and II, Italian Creek, Muttontown Gully and Clyde West. Evidence for Māori occupation of specific sites in

4884-694: The Llanquihue in Chile and the Otiran in New Zealand. The Holocene can be subdivided into five time intervals, or chronozones , based on climatic fluctuations: Geologists working in different regions are studying sea levels, peat bogs, and ice-core samples, using a variety of methods, with a view toward further verifying and refining the Blytt–Sernander sequence . This is a classification of climatic periods initially defined by plant remains in peat mosses . Though

5032-628: The North Atlantic ocean . Furthermore, studies show that the melting of Lake Agassiz led to sea-level rise which flooded the North American coastal landscape. The basal peat plant was then used to determine the resulting local sea-level rise of 0.20-0.56m in the Mississippi Delta . Subsequent research, however, suggested that the discharge was probably superimposed upon a longer episode of cooler climate lasting up to 600 years and observed that

5180-462: The Roxburgh Gorge south of Alexandra. Long-associated with gold mining, orchards and the production of stone fruit , the gorge (including part of old Cromwell) was flooded in the early 1990s to form Lake Dunstan behind the hydroelectric Clyde Dam . The former Otago Central Railway which traced the river through the gorge from Clyde was removed, while State Highway 8 was realigned above

5328-565: The Tien Shan , sedimentological evidence from Swan Lake suggests the period between 8,500 and 6,900 BP was relatively warm, with steppe meadow vegetation being predominant. An increase in Cyperaceae from 6,900 to 2,600 BP indicates cooling and humidification of the Tian Shan climate that was interrupted by a warm period between 5,500 and 4,500 BP. After 2,600 BP, an alpine steppe climate prevailed across

5476-535: The sixth mass extinction or Anthropocene extinction , is an ongoing extinction event of species during the present Holocene epoch (with the more recent time sometimes called Anthropocene) as a result of human activity . The included extinctions span numerous families of fungi , plants , and animals , including mammals , birds , reptiles , amphibians , fish and invertebrates . With widespread degradation of highly biodiverse habitats such as coral reefs and rainforests , as well as other areas,

5624-480: The 1860s. With several settlements quickly established along gold-rich rivers such as the Clutha and Kawarau , the rush to Central Otago was the largest in the region's history. A large number of miners' huts also existed during this era along the Clutha River. Roxburgh Gorge had a majority of the huts of this type, but they also occurred in Cromwell Gorge. A 1980 archaeological survey in the Roxburgh Gorge indicated

5772-450: The Clutha catchment . It has the biggest catchment and outflow in New Zealand. About 6% of all water in the South Island is discharged by the Clutha River alone. It has a mean discharge of approximately 500 m (18,000 cu ft) and a catchment area of around 22,000 km (8,500 sq mi) and is an economically significant river for the country. The Clutha River encompasses two hydropower stations, which provide 14% of

5920-581: The Clutha Catchment's rapidly expanding water needs will become more challenging in the future. Located at a maximum elevation of approximately 2,800 m (9,200 ft) on the Main Divide of the Southern Alps, the majority of the river's headwater flows originate from the melting of alpine snow cover and rainfall, with glaciers contributing a minor amount. In inland basins, annual precipitation totals can be less than 400 mm (16 in), while on

6068-564: The Clutha River in the Lowburn area. Initial thoughts on harnessing the Clutha River for hydroelectric power occurred at least as early as 1904, but it was not until the 1940s that it began to be a more serious option for power in Otago. An examination of the Clutha River's potential in 1944 culminated in the selection and construction of the Roxburgh Dam with first power being produced in 1956. By 1968,

Cromwell Gorge - Misplaced Pages Continue

6216-754: The Clutha River include Alexandra, New Zealand , Balclutha, Cromwell, Roxbrugh , and Wānaka . The Clutha River extends about 340 km (210 mi), flowing roughly north to south through the Otago Region. The Clutha River's headwaters are located in the Southern Alps , receiving up to 8,000 mm (310 in) of precipitation annually from the west and north west. The Clutha River and its tributaries receive water from three lakes in Otago, Hāwea , Wakatipu , and Wānaka , along with its minor tributaries Arrow, Beaumont, Lindis, Manuherikia, Nevis, Shotover, Talla Burn, Teviot, and Pomahaka. The Clutha River may have taken its current course due to glacial advances in

6364-416: The Clutha River use it as a source for treatment plants to provide communities with potable water. Further dam projects have been proposed for the river, but as of 2012, all have been cancelled. The Clutha provides irrigation for stone fruit orchards and vineyards around Cromwell, Alexandra, and Roxburgh, which grow apples, apricots, nectarines, cherries, peaches and grapes. There are more vineyards in

6512-590: The Clyde Dam in 1982 and was completed in 1993. It was a somewhat controversial project, with opposition and criticism from environmentalists and local residents. Completion of the Clyde Dam took much longer than expected, at a final cost more than 45% higher than the first estimate. The Clyde Dam was one of Robert Muldoon 's and the Third National Government 's " Think Big " projects, an interventionist state economic strategy. Several Local Authorities along

6660-448: The Cromwell Gorge and eggshell fragments found in many shelters confirm their usage. If early Māori hunters recognised such a regularity in moa ecology, it seems likely that they would undertake seasonal or regular raids on nesting areas. The first European to set eyes on the Cromwell Gorge was Nathanael Chalmers who first traversed the valley in 1853, accompanied by two Māori guides: Reko, a Ngāi Tahu chief from Tuturau , and Kaikōura,

6808-603: The Cromwell Gorge was well-documented during the Clutha Valley Archaeological Project resulting from the decision to build the Clyde Dam. Despite the limited number of samples available, rock shelters and adjacent sites showed the following finds to be culturally significant: It has been suggested that the numerous overhangs within the craggy rock formations of the Central Otago river gorges may have been favoured moa nesting locations. Such locations abound in

6956-548: The Cromwell Gorge, upon which moa grazed. Today in spring and summer the gorge blossoms with wild flowers: the purple of thyme, the blue of Vipers bugloss , the red of Spur valerian , and the yellows of Californian poppy and stone crop . The first settlers in the region were the Māori as they travelled through Central Otago en route to the West Coast on pounamu expeditions, as well as in search of seasonal food resources. Although

7104-470: The Dunstan Fault has extended south-west towards Clyde, rather than being translated along the southern margin of the Cairnmuir Mountains. This is important as it suggests that there is no recent activity on the transfer zone between the Dunstan and Earnscleugh Faults. This transfer zone is controlled by the well-documented River Channel Fault, a steeply dipping fault mapped as running down the centre of

7252-412: The Dunstan goldfield. By the end of 1864 the easily won gold had been mined and many had moved off to other more lucrative fields. At the turn of the twentieth century, the gorge would once again see a feverish gold rush, but this time on a more industrial scale as large mechanical dredges made large returns. In 1900 there were 187 dredges being operated on the Clutha River, but like the earlier gold rush,

7400-648: The Earth to warm. Likewise, climatic changes have induced substantial changes in human civilisation over the course of the Holocene. During the transition from the last glacial to the Holocene, the Huelmo–Mascardi Cold Reversal in the Southern Hemisphere began before the Younger Dryas, and the maximum warmth flowed south to north from 11,000 to 7,000 years ago. It appears that this was influenced by

7548-579: The Government felt that the Clutha River was under-utilised, especially in comparison to the Waitaki River which by this time had the Waitaki Dam, Benmore Dam and Aviemore Dam . The same year, a committee was setup to investigate additional hydroelectric options on the Clutha River and by 1971 had come up with six potential options (Schemes A through F). These would later (1973) be added to by several additional schemes, in particular Scheme H which called for

SECTION 50

#1732848604975

7696-463: The Holocene Epoch. A 1,500-year cycle corresponding to the North Atlantic oceanic circulation may have had widespread global distribution in the Late Holocene. From 8,500 BP to 6,700 BP, North Atlantic climate oscillations were highly irregular and erratic because of perturbations from substantial ice discharge into the ocean from the collapsing Laurentide Ice Sheet. The Greenland ice core records indicate that climate changes became more regional and had

7844-474: The Holocene has shown significant variability despite ice core records from Greenland suggesting a more stable climate following the preceding ice age. Marine chemical fluxes during the Holocene were lower than during the Younger Dryas, but were still considerable enough to imply notable changes in the climate. The temporal and spatial extent of climate change during the Holocene is an area of considerable uncertainty, with radiative forcing recently proposed to be

7992-480: The Holocene, however, the domestication of plants and animals allowed humans to develop villages and towns in centralized locations. Archaeological data shows that between 10,000 and 7,000 BP rapid domestication of plants and animals took place in tropical and subtropical parts of Asia , Africa , and Central America . The development of farming allowed humans to transition away from hunter-gatherer nomadic cultures, which did not establish permanent settlements, to

8140-448: The Kawarau River, leading Chalmers to write: The water flow almost doubled and was suddenly confined in the great Cromwell Gorge ... I shall never forget the "race" through the gorge ... my heart was literally in my mouth, but those two old men seemed to care nothing for the current. When they emerged from the gorge at the site of the present-day Clyde Dam, he wrote " then our troubles were over ". Chalmers' early foray into Central Otago

8288-514: The Lakes District ( Kingston / Queenstown ) via the Kawerau Gorge and not the Cromwell Gorge at the time. Reference to a railway, presumably through the Cromwell Gorge, linking to the Taieri Railway was also made in 1877, but nothing would come of this for another thirty years. The railway finally made it as far as Clyde in 1907, with the station's official opening on 2 April 1907 by the prime minister, William Hall-Jones . The Cromwell Railway and Progress League, having been formed in 1906 to influence

8436-437: The Late Holocene, the ISM became weaker, although this weakening was interrupted by an interval of unusually high ISM strength from 3,400 to 3,200 BP. Southwestern China experienced long-term warming during the Early Holocene up until ~7,000 BP. Northern China experienced an abrupt aridification event approximately 4,000 BP. From around 3,500 to 3,000 BP, northeastern China underwent a prolonged cooling, manifesting itself with

8584-476: The Late Holocene. Animal and plant life have not evolved much during the relatively short Holocene, but there have been major shifts in the richness and abundance of plants and animals. A number of large animals including mammoths and mastodons , saber-toothed cats like Smilodon and Homotherium , and giant sloths went extinct in the late Pleistocene and early Holocene. These extinctions can be mostly attributed to people. In America, it coincided with

8732-408: The Middle Holocene was notable for its warmth, with rhythmic temperature fluctuations every 400-500 and 1,000 years. Before 7,500 BP, the Gulf of Thailand was exposed above sea level and was very arid. A marine transgression occurred from 7,500 to 6,200 BP amidst global warming. During the Middle Holocene, western North America was drier than present, with wetter winters and drier summers. After

8880-465: The Middle to Late Holocene, the coastline of the Levant and Persian Gulf receded, prompting a shift in human settlement patterns following this marine regression. Central Asia experienced glacial-like temperatures until about 8,000 BP, when the Laurentide Ice Sheet collapsed. In Xinjiang , long-term Holocene warming increased meltwater supply during summers, creating large lakes and oases at low altitudes and inducing enhanced moisture recycling. In

9028-500: The Māori name as "Matou" and "Matua-a", and pronounced it "Mattoo". Māori also referred to the Clutha River as Maranuku . The first appearance of a European name for the Clutha River / Mata-Au was the Molyneux River ( / m ɒ l ɪ n ˌ ə ʊ / ); its mouth was named by Captain James Cook after his sailing master, Robert Molineux. The name is also applied to the small settlement of Port Molyneux . Early maps show Moulineux Harbour in its original spelling, but later maps indicate

SECTION 60

#1732848604975

9176-417: The Roxburgh Dam was built, the Cromwell Gorge would reveal a rich wealth of mining era (1862-1890) and some pre-European sites. In all, 44 rock shelters were recorded in the Cromwell Gorge. Over the duration of the project, approximately 2000 sites were added to the national site recording scheme with almost every farm in the Upper Clutha being systematically surveyed. Perhaps the greatest site of interest of

9324-504: The South Island to recognise the "equal and special significance" of both the English and Māori names. Māori occupation of the Otago Region began in c.  1250–1300 . Māori learned to hunt the numerous species of moa and burned many of the inland forests. The first iwi in Otago were Waitaha , then Kāti Māmoe ; later came Kāi Tahu . By the end of the fourteenth century, the environment in Otago and Southland (Murihuku) had begun to shift, with podocarp woods retreating and

9472-426: The South Island's hydroelectric power supply to the New Zealand power grid . The Clutha River's first dam was the Nil Desperandum Dam in the Upper Clutha Valley, existing from 1864–66. The Roxburgh Dam was the first substantial dam in the South Island. Construction on the dam began in 1949. Four turbines were installed in 1956–57 and four more in 1960–61. Its installed capacity is 320MW. Construction began on

9620-450: The South Island, a whaling station was established close to the Clutha River's mouth at Port Molyneux , and during this period the sea was the source of almost all of the area's economy. The town of Port Molyneux, located on this bay, was a busy harbour during the 19th century. Its location at the mouth of the Clutha made it a good site for trade, both from the interior and for coastal and ocean-going shipping. A major flood in 1878 shifted

9768-468: The area as "well grassed and watered, a very land of promise" which attracted others to the region. In 1862, gold-rich bars of rocks and gravel were discovered by Christopher Reilly and Horatio Hartley during their winter 1862 expedition up Cromwell Gorge through the waters of the Clutha. They arrived in Dunedin on 15 August, 1862, deposited their 100 oz (2,800 g) of gold, and were rewarded with £2,000. A gold rush began in Central Otago in

9916-436: The area's potential was gradually recognised. Previously, the Kawarau River and the Clutha River running downstream from Cromwell were the primary focus. Māori were aware of gold in the Clutha River but they did not value it. The Clutha River is the South Island's largest river and has the largest catchment and outflow in New Zealand. About 6% of all water in the South Island is discharged through Clutha River alone. It has

10064-471: The arrival of the Clovis people; this culture was known for " Clovis points " which were fashioned on spears for hunting animals. Shrubs, herbs, and mosses had also changed in relative abundance from the Pleistocene to Holocene, identified by permafrost core samples. Throughout the world, ecosystems in cooler climates that were previously regional have been isolated in higher altitude ecological "islands". The 8.2-ka event , an abrupt cold spell recorded as

10212-443: The basin and range topography of parallel ridges and basins with steep south-eastern limbs and gently-dipping north-western flanks. The Cromwell Gorge exits the Dunstan and Cairnmuir Mountains immediately to the north of Clyde. Both mountain ranges are controlled to the south-east by large reverse faults; the Dunstan Fault and Earnscleugh Fault, respectively. Investigations have found that geologically-recent deformation associated with

10360-409: The best of times it is dangerous with a considerable amount of horse traffic, and an accident at any point of the gorge means sudden death. "Irrigation first", was the Government's reply, reflecting their desire to harness the economic benefits of the Country's nascent agricultural potential. The Government's response was nothing new, having espoused this priority since at least 1899. This would not stop

10508-421: The catchment. A 2022 study by Diversity and Distributions revealed that the river is home to a diverse range of Galaxias vulgaris clades; its diversity is likely a reflection of the Clutha River's complex geological processes. The study emphasises the importance of the genome -wide methods to identify species and understand biodiversity in freshwater ecosystems and conservation in the Clutha River. Before

10656-478: The climate, Greenlandian (11,700 years ago to 8,200 years ago), Northgrippian (8,200 years ago to 4,200 years ago) and Meghalayan (4,200 years ago to the present), as proposed by International Commission on Stratigraphy . The oldest age, the Greenlandian, was characterized by a warming following the preceding ice age. The Northgrippian Age is known for vast cooling due to a disruption in ocean circulations that

10804-425: The construction of Roxburgh Dam , salmon could be found traversing the length of the Clutha River and spawning as far upstream as Lakes Hāwea and Wānaka. The Clutha is the southernmost recognised salmon river; salmon continue to arrive each spring and summer, though numbers have decreased since the construction of Roxburgh Dam. Common bullies , smelt , and perch are also found in the river. A 1981 assessment of

10952-473: The country's hydropower generation capacity. The Clutha River drains the high mountains of the Southern Alps in the west and passes through a complex topographic system of basins and ranges towards the east before reaching into the Pacific Ocean . A majority of the topographical features of the Clutha River catchment area are a direct result of the late Cenozoic and active tectonic processes that are occurring in southern South Island due to deformation along

11100-491: The dam site. The filling of the Clyde Dam resulted in the loss of significant sites of cultural interest in the Cromwell Gorge and other areas inundated by Lake Dunstan. Knowing this would be the case, the Ministry of Works commissioned archaeological surveys of the gorge and surrounding areas that would be impacted by the filling of Lake Dunstan. The initial studies in 1976–1977 revealed that more than 150 sites would be affected by

11248-450: The disruption of Bronze Age civilisations in the region. Eastern and southern China, the monsoonal regions of China, were wetter than present in the Early and Middle Holocene. Lake Huguangyan's TOC, δ C wax , δ C org , δ N values suggest the period of peak moisture lasted from 9,200 to 1,800 BP and was attributable to a strong East Asian Summer Monsoon (EASM). Late Holocene cooling events in

11396-473: The early part of the Holocene and another 30 m in the later part of the Holocene. In addition, many areas above about 40 degrees north latitude had been depressed by the weight of the Pleistocene glaciers and rose as much as 180 m (590 ft) due to post-glacial rebound over the late Pleistocene and Holocene, and are still rising today. The sea-level rise and temporary land depression allowed temporary marine incursions into areas that are now far from

11544-427: The end of the last strong phase. Ice core measurements imply that the sea surface temperature (SST) gradient east of New Zealand, across the subtropical front (STF), was around 2 degrees Celsius during the HCO. This temperature gradient is significantly less than modern times, which is around 6 degrees Celsius. A study utilizing five SST proxies from 37°S to 60°S latitude confirmed that the strong temperature gradient

11692-601: The end of the thermal maximum of the HCO around 4,500 BP, the East Greenland Current underwent strengthening. A massive megadrought occurred from 2,800 to 1,850 BP in the Great Basin . Eastern North America underwent abrupt warming and humidification around 10,500 BP and then declined from 9,300 to 9,100 BP. The region has undergone a long term wettening since 5,500 BP occasionally interrupted by intervals of high aridity. A major cool event lasting from 5,500 to 4,700 BP

11840-459: The entire ten-year project was the excavation of Cromwell's Chinatown at the confluence of the Clutha and Kawarau Rivers. The site had been abandoned since the 1920s when it was excavated over a 10-week period in 1980, many of the artifacts going on display in the Cromwell Museum. Clutha River The Clutha River ( Māori : Mata-Au , officially gazetted as Clutha River / Mata-Au )

11988-434: The exception of upland bully , common river galaxias and roundhead galaxias . All native species are diadromous , meaning that they are recorded from the tributaries, and giant kōkopu and kōaro likely went through the mainstem while on their way to its tributaries. The Clutha River has a limited collection of native species, though it does provide a through route for the many other diadromous species. Brown trout are

12136-431: The extension of the railway through the gorge to Cromwell, set about lobbying the Government with increasing frequency. However, work on the railway line stopped at Clyde until 1914. The lobby group stressed the high cost of transport between Cromwell and Clyde, the impact on the region's farmers and also pointed to the inadequacies of the road: The road through the gorge is a narrow one, with some very sharp bends, and at

12284-579: The extent of the area affected was unclear. The beginning of the Holocene corresponds with the beginning of the Mesolithic age in most of Europe . In regions such as the Middle East and Anatolia , the term Epipaleolithic is preferred in place of Mesolithic, as they refer to approximately the same time period. Cultures in this period include Hamburgian , Federmesser , and the Natufian culture , during which

12432-425: The filling of the proposed dam(s) in the Cromwell Gorge. Given the large number of sites affected, a project archaeologist was employed for an initial period of five years, which was later increased to ten years due to the sheer enormity of excavating and cataloguing the sites which would be impacted by the damming of the Clutha River. Unlike the Roxburgh Gorge, where no archaeological survey was ever undertaken before

12580-513: The gorge and directly beneath the Clyde Dam. The former Clutha River followed several of these faults as it coursed through the Cromwell Gorge. Vegetation in the Cromwell Gorge has seen considerable change, as has the wider Central Otago region, since at least the Holocene (10,000 years until present). The arrival of humans in Central Otago resulted in particularly extensive changes in vegetation as Māori hunter-gatherers used clearance fires improvidently. Early Māori firing of woody cover from about

12728-555: The gorge is bound by the Dunstan Mountains and to the west, the Cairnmuir Mountains. The overall relief from the highest point of the gorge (Leaning Rock, 1647 m) and the floor of the gorge (Lake Dunstan, 194 m) is 1,453 m (4,767 ft). The Cromwell Gorge is the entrance to the Upper Clutha Valley and was historically an important thoroughfare for early Māori moa hunters, and later pastoralists and gold miners in

12876-550: The gorge where they lived a hard life in harsh conditions, often in rock shelters. The first camp established was near Gibraltar Rock ( 45°04′38″S 169°13′58″E  /  45.0773°S 169.2329°E  / -45.0773; 169.2329 ) in the Cromwell Gorge, although a far more substantial settlement in the 1870s formed Cromwell's Chinatown . Deserted by the turn of the century, the wooden stores and businesses were demolished in 1930. Chinese were not always popular or welcome, and often blamed for things they did not do. This

13024-422: The gorge. Work during the dam's early construction phase in 1982 identified numerous faults and shear zones beneath the dam – in particular, the River Channel Fault. Despite considerable amounts of concrete being pumped into tunnels across the fault to act as shear pins, the faults posed a significant risk and forced a redesign of the dam leading to the incorporation of a controversial slip joint . The slip joint

13172-706: The harbour's name was written as "Molyneux", rather than "Moulineux". The river is now commonly known as the Clutha, which comes from Cluaidh , the Scots Gaelic name for the River Clyde in Scotland , which runs through Glasgow . The official name for the river has been Clutha River / Mata-au since the Ngāi Tahu Claims Settlement Act 1998 , a landmark Treaty of Waitangi settlement , which added dual names to approximately 90 geographic features throughout

13320-477: The high dam becoming part of the National Government's Think Big policy. Construction of the Clyde Dam was started in 1977 and first required the excavation of a diversion channel for the Clutha River. The diversion channel was cut down 22 m (72 ft) into the gravel and bedrock on the true right bank of the river. At 50 m (160 ft) wide and 700 m (2,300 ft) long, it facilitated

13468-474: The journey (some fifty seven years after the fact) stating that the shortest way back to Southland would be to build a flax fibre mokihi or raft and ride it all the way down the Clutha River. As they set off from Lake Hāwea and entered the Clutha Rive, Chalmers wrote that they: ... paddled down the river so rapidly that I could hardly credit our speed Within half a day, they came to the Clutha's junction with

13616-423: The last glacial period and then classify climates of more recent prehistory . Paleontologists have not defined any faunal stages for the Holocene. If subdivision is necessary, periods of human technological development, such as the Mesolithic , Neolithic , and Bronze Age , are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of

13764-529: The late nineteenth century. It remains an important access route into Central Otago's interior via State Highway 8 (SH8). The Cromwell Gorge is dominated by the characteristic rocky tors and craggy outcrops of the Haast Schist Group ; grey quartzofeldspathic metagreywacke interlayered with micaceous meta-argillite and greenschist formed during the Rangitata Orogeny . The schist in Central Otago has

13912-583: The lower parts of what is presently the Manuherikia Valley near Alexandra. By Christmas 1861, 14,000 prospectors were on the Tuapeka and Waipori fields. The gold rush was short-lived, with most of the alluvial gold played out by 1863, but prospectors continued to arrive, swelling to a maximum of 18,000 miners in February 1864. Mining in the Clutha River upstream from Cromwell became significant after 1900, when

14060-451: The lower slopes. Uncontrolled burn-offs, over-grazing, and the introduction of the rabbit in the mid-1800s, have heavily modified the vegetation cover since European settlement. This is further worsened by Central Otago being the driest region in New Zealand. Those areas of the gorge which are the driest are dominated by cushions of scabweed , sweet briar rosehip , and thyme , all of which flourish. The introduction of thyme to Central Otago

14208-623: The lower stretches of the river. Murikauhaka, a settlement near the mouth of the Mata-au, was at one stage home to an estimated two hundred people. Māori trading groups used the Cromwell Gorge as the main thoroughfare to their pounamu and moa-hunting expeditions to the interior of Otago. Many early Māori archaeological sites have been found in the Cromwell Gorge, featuring moa eggshell fragments. Unlike other Central Otago sites, no burned bones have been found. During early European settlement in

14356-411: The method was once thought to be of little interest, based on C dating of peats that was inconsistent with the claimed chronozones, investigators have found a general correspondence across Eurasia and North America . The scheme was defined for Northern Europe , but the climate changes were claimed to occur more widely. The periods of the scheme include a few of the final pre-Holocene oscillations of

14504-522: The mid-19th century. The LIA was the coldest interval of time of the past two millennia. Following the Industrial Revolution, warm decadal intervals became more common relative to before as a consequence of anthropogenic greenhouse gases, resulting in progressive global warming. In the late 20th century, anthropogenic forcing superseded variations in solar activity as the dominant driver of climate change, though solar activity has continued to play

14652-698: The mid-Holocene (8.2 - 4.2 k cal BP). Climate change on seasonality and available moisture also allowed for favorable agricultural conditions which promoted human development for Maya and Tiwanaku regions. In the Korean Peninsula , climatic changes fostered a population boom during the Middle Chulmun period from 5,500 to 5,000 BP, but contributed to a subsequent bust during the Late and Final Chulmun periods, from 5,000 to 4,000 BP and from 4,000 to 3,500 BP respectively. The Holocene extinction , otherwise referred to as

14800-669: The middle to late- Pleistocene , advances that nearly reached Cromwell. It is an economically significant river for the country. The Clutha River encompasses two hydropower stations, which provide 14% of the country's hydropower generation capacity. It drains the largest catchment in New Zealand, which is about 22,000 km (8,500 sq mi) in size, and has an area normalised flow of about 800 mm (31 in). It has an average annual discharge of 530 m (19,000 cu ft). Due to long-standing hydroelectricity commitments and increasing demands for urban water supply and irrigation for horticulture and agriculture , meeting

14948-404: The moa population declining. A few Māori settlements in the region started to lose importance, although several settlements still existed in Central Otago . Several locations along the Clutha River retain the names of Kāti Māmoe chiefs, such as, Taumata-o-Te-Hau , a hill on the north side of the Clutha River, above Balclutha , named after the chief who climbed there and watched for the arrival of

15096-512: The most encountered fish in the Clutha River, occurring throughout the main river, streams, and nearby lakes. Rainbow trout also appear in the river but in smaller numbers, and they are more common in the lower section of the river compared to the upper stretches. At the minimum, nine species of freshwater-limited Galaxias have been identified in the Clutha River by genetics and morphology . A Nationally Critical species of Galaxias called "Clutha flathead species D" occurs in various parts of

15244-570: The most powerful factor affecting surface processes. The sedimentary record from Aitoliko Lagoon indicates that wet winters locally predominated from 210 to 160 BP, followed by dry winter dominance from 160 to 20 BP. North Africa, dominated by the Sahara Desert in the present, was instead a savanna dotted with large lakes during the Early and Middle Holocene, regionally known as the African Humid Period (AHP). The northward migration of

15392-481: The mouth of the Clutha to the north and silted up the port, after which the town gradually dwindled. The first European to visit the Upper Clutha area and to see the inland lakes of Wakatipu , Wānaka and Hāwea was Nathanael Chalmers , who was guided by Chiefs Reko and Kaikōura in 1853. They returned him down the river on a mōkihi , a flax reed open kayak, that they built from flax stems and raupō from

15540-639: The nearby plate boundary, defined by the Alpine Fault . The river is known for its scenery, gold-rush history, and swift turquoise waters. A river conservation group, the Clutha Mata-Au River Parkway Group , is working to establish a regional river parkway, with a trail, along the entire river corridor. The Māori name for the Clutha River is the Mata-Au (sometimes shortened to Matau), meaning 'surface current'. Early settlers sometimes spelled

15688-406: The newly-formed lake. The Dunstan Trail, a major new cycle route, was opened on the lake's right bank in 2021. The Cromwell Gorge formed in response to the uplift of the Dunstan and Cairnmuir Mountains and simultaneous antecedent incision by the Clutha River. At the northern (upstream) entrance to the gorge lies the township of Cromwell, while the township of Clyde lies to the south. To the east,

15836-748: The north to Invercargill in the south. The town of Wyndham was completely evacuated, and the towns of Balclutha , Milton and Mataura were seriously affected with many residents moved. The small settlement of Kelso on the banks of the Pomahaka River was completely abandoned and was not rebuilt once the waters subsided. At its peak, on 15 October, the Clutha's flow was measured at just over 4,500 cubic metres per second (160,000 cu ft/s). A major flood in November 1999 seriously damaged river communities, especially Alexandra . The flooding in Alexandra

15984-518: The oldest inhabited places still existing on Earth were first settled, such as Tell es-Sultan (Jericho) in the Middle East . There is also evolving archeological evidence of proto-religion at locations such as Göbekli Tepe , as long ago as the 9th millennium BC . The preceding period of the Late Pleistocene had already brought advancements such as the bow and arrow , creating more efficient forms of hunting and replacing spear throwers . In

16132-596: The origin of cycles identified in the North Atlantic region. Climate cyclicity through the Holocene ( Bond events ) has been observed in or near marine settings and is strongly controlled by glacial input to the North Atlantic. Periodicities of ≈2500, ≈1500, and ≈1000 years are generally observed in the North Atlantic. At the same time spectral analyses of the continental record, which is remote from oceanic influence, reveal persistent periodicities of 1,000 and 500 years that may correspond to solar activity variations during

16280-553: The period exceeds any likely tectonic uplift of non-glacial origin. Post-glacial rebound in the Scandinavia region resulted in a shrinking Baltic Sea . The region continues to rise, still causing weak earthquakes across Northern Europe. An equivalent event in North America was the rebound of Hudson Bay , as it shrank from its larger, immediate post-glacial Tyrrell Sea phase, to its present boundaries. The climate throughout

16428-483: The present. The human impact on modern-era Earth and its ecosystems may be considered of global significance for the future evolution of living species, including approximately synchronous lithospheric evidence, or more recently hydrospheric and atmospheric evidence of the human impact. In July 2018, the International Union of Geological Sciences split the Holocene Epoch into three distinct ages based on

16576-556: The region were dominantly influenced by solar forcing, with many individual cold snaps linked to solar minima such as the Oort, Wolf , Spörer , and Maunder Minima . A notable cooling event in southeastern China occurred 3,200 BP. Strengthening of the winter monsoon occurred around 5,500, 4,000, and 2,500 BP. Monsoonal regions of China became more arid in the Late Holocene. In the Sea of Japan,

16724-597: The region. Sand dune evolution in the Bayanbulak Basin shows that the region was very dry from the Holocene's beginning until around 6,500 BP, when a wet interval began. In the Tibetan Plateau, the moisture optimum spanned from around 7,500 to 5,500 BP. The Tarim Basin records the onset of significant aridification around 3,000-2,000 BP. After 11,800 BP, and especially between 10,800 and 9,200 BP, Ladakh experienced tremendous moisture increase most likely related to

16872-611: The representations, however. An announcement to restart the railway extension was made in March 1914, and works were established in the following months with new surveys taking place. The railway started in earnest in September and by the end of 1916 some 8.5 mi (13.7 km) of rail had been laid. The line to Cromwell was not completed until July 1921 – significantly overrunning the predicted two to three years it would take. An E class (Double Fairlie locomotive) , Josephine , which pulled all

17020-628: The residual glacial ice remaining in the Northern Hemisphere until the later date. The first major phase of Holocene climate was the Preboreal . At the start of the Preboreal occurred the Preboreal Oscillation (PBO). The Holocene Climatic Optimum (HCO) was a period of warming throughout the globe but was not globally synchronous and uniform. Following the HCO, the global climate entered

17168-578: The river by the Upper Clutha Valley Development with the Ministry of Works and Development emphasised the high-quality waters of the river and very low levels of phytoplankton biomasses present. Several major floods have occurred on the Clutha, most notably the "Hundred year floods" of October 1878 and October 1978. During the October 1878 flood, snow from the Southern Alps began to melt and

17316-462: The river started to rise. Central Otago experienced widespread flooding and farm buildings were submerged to their rooftops while rivers filled with dead horses and sheep, timber from farms and mine workings, and trees with a diameter of 1 m (3 ft 3 in). A bridge in Clyde collapsed on 29 September, and its wreckage floated down to Roxburgh, where it struck a bridge there. The bridges at Bannockburn, Beaumont and Roxbrugh were swept away. As

17464-568: The runholders who had previously acquired territory up to the Waitāhuna River . When they returned to Dunedin after spending several days exploring the Manuherikia Valley, they submitted an application to the Otago Provincial Government to lease two blocks of land on either side of the Manuherikia River. The total land area was 100,000 acres (40,000 hectares). They brought sheep to the district in 1858. Watson Shennan described

17612-473: The safe construction of the remainder of the dam. The river was diverted in 1982, at which point temporary coffer dams had been conducted to enable building of the dam's concrete superstructure. A cable crane attached to pylons delivered the majority of the 1.2 × 10 ^  m (42 × 10 ^  cu ft) of concrete required to build the dam and its associated powerhouse. At its peak between 1986 and 1987, approximately 1000 dam workers were on site. The dam

17760-400: The sea. For example, marine fossils from the Holocene epoch have been found in locations such as Vermont and Michigan . Other than higher-latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain , and cave deposits. Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during

17908-693: The shores of Lake Hāwea. In 1910, 57 years after the event, Nathanael Chalmers remembered his boat trip through the Cromwell Gorge: "I shall never forget the "race" through the gorge ... my heart was literally in my mouth, but those two old men seemed to care nothing for the current." European "sheepmen" arrived later in the late 1850s, searching for grazing grounds in Otago's interior. Alexander and Watson Shennan set off from Milton (known previously as Tokomairiro) in December 1857 to Central Otago, looking for land to raise sheep. The brothers proceeded farther than

18056-438: The southern end of the gorge on what would become Fruitgrowers Road. In 1901 William Annan cleared his piece of land, built a cob shelter, and planted his fruit trees. Imported from Australia, the first trees Annan planted were a diverse mix to test what would be most suitable for the challenging Central Otago climate and included citrus, almond, walnut, cherry, apricot, apple, pear, peach, nectarine, quince and grape. By 1914 he had

18204-721: The strengthening of the Indian Summer Monsoon (ISM). From 9,200 to 6,900 BP, relative aridity persisted in Ladakh. A second major humid phase occurred in Ladakh from 6,900 to 4,800 BP, after which the region was again arid. From 900 to 1,200 AD, during the MWP, the ISM was again strong as evidenced by low δ O values from the Ganga Plain. The sediments of Lonar Lake in Maharashtra record dry conditions around 11,400 BP that transitioned into

18352-779: The term 'Flandrian' may be used as a synonym for Holocene, although it is becoming outdated. The International Commission on Stratigraphy, however, considers the Holocene to be an epoch following the Pleistocene and specifically following the last glacial period . Local names for the last glacial period include the Wisconsinan in North America , the Weichselian in Europe, the Devensian in Britain,

18500-450: The thirteenth century resulted in a vastly different vegetation in the Cromwell Gorge. Initial woody cover included totara ( Podocarpus hallii ) and beech forest ( Nothofagus menziesii ) over what is now a treeless Central Otago. Grassland and scrub now cover most of Central Otago. On the former valley floor of the Cromwell Gorge, low tussock grassland of several varieties dominated, while manuka , kānuka and matagouri scrub patched

18648-677: The times of the dredges drew to a close only several years later. In 1865, the Otago Provincial Council invited Chinese miners working on the Victorian goldfields in Australia, to rework the Otago goldfields. European miners had departed in their droves for more lucrative goldfields in Marlborough and the West Coast , opening the door for Chinese mining immigrants to come directly from China, particularly Guangdong province. Many mined in

18796-532: The trains in the gorge during the construction era, is now a museum piece in the Otago Settlers Museum . Cromwell was the terminus of the Otago Central Railway and consisted of a railway station building, five staff houses, a 6000 gallon locomotive watering tank, stockyards, an engine-shed, turntable coal facilities and the station sidings were able to accommodate nearly 100 wagons. At the time, it

18944-503: The upper reaches of the river at Bannockburn , Bendigo , Tarras and Wānaka . Holocene The Holocene correlates with the last maximum axial tilt of the Earth towards the Sun, and corresponds with the rapid proliferation, growth, and impacts of the human species worldwide, including all of its written history , technological revolutions , development of major civilizations , and overall significant transition towards urban living in

19092-574: The western edge of the catchment, they can surpass 4,000 mm (160 in). The contribution of snowmelt to the annual streamflow of the Clutha River is estimated to be 10% by the time it reaches the Southern Pacific Ocean . This proportion is considerably higher for alpine sub-catchments and large inland basins, rising as high as 30% to 50%. A number of large tributaries originate in Central Otago's semi-arid basins, where yearly precipitation can be as low as 400 mm (16 in), which

19240-590: The working group's parent bodies (ultimately the International Union of Geological Sciences ). In March 2024, after 15 years of deliberation, the Anthropocene Epoch proposal of the working group was voted down by a wide margin by the SQS, owing largely to its shallow sedimentary record and extremely recent proposed start date. The ICS and the International Union of Geological Sciences later formally confirmed, by

19388-578: The world. Some scholars have argued that a third epoch of the Quaternary, the Anthropocene , has now begun. This term has been used to denote the present time-interval in which many geologically significant conditions and processes have been profoundly altered by human activities. The 'Anthropocene' (a term coined by Paul J. Crutzen and Eugene Stoermer in 2000) was never a formally defined geological unit. The Subcommission on Quaternary Stratigraphy (SQS) of

19536-563: The world. This ' Neolithic Revolution ', likely influenced by Holocene climatic changes, included an increase in sedentism and population, eventually resulting in the world's first large-scale state societies in Mesopotamia and Egypt . During the Middle Holocene, the Intertropical Convergence Zone , which governs the incursion of monsoon precipitation through the Arabian Peninsula, shifted southwards, resulting in increased aridity. In

19684-442: Was 'jealous of the pre-eminence' accorded Hartley as the discoverer. Within days of the announcement of Hartley and Reilly's discovery, 2000 miners had descended on the Dunstan goldfield with the first gold export to leave the goldfield on 6 October 1862 carrying some 6030 t oz (187.5 kg) of gold. Between 1 September 1862 and 1 April 1863, 120,886 t oz (3760 kg) of gold were recovered from Otago, with most of this coming from

19832-417: Was around 2.1 metres above present and occurred about 5,800 to 5,000 BP. Sea levels at Rocas Atoll were likewise higher than present for much of the Late Holocene. The Northwest Australian Summer Monsoon was in a strong phase from 8,500 to 6,400 BP, from 5,000 to 4,000 BP (possibly until 3,000 BP), and from 1,300 to 900 BP, with weak phases in between and the current weak phase beginning around 900 BP after

19980-493: Was attributed to a rise in the riverbed resulting from silt loading in the Roxburgh reservoir behind the Roxburgh Dam , downriver from the town. The 1999 flood had significantly higher water levels in Alexandra than the 1878 flood, despite being only 80% of the volume of the latter. There are two hydroelectric power stations on the Clutha River, the 464MW Clyde Dam and the 320MW Roxburgh Dam , which together provide about 22% of

20128-423: Was blissfully ignorant of ahead of his expedition. Unfortunately for Chalmers, he contracted a bout of chronic diarrhoea early into his trip and suffered with it for many weeks. Having eventually made it as far as Lakes Wakatipu , Hāwea and Wānaka, his illness got the better of him and he realised he would not be able to make it to Waitaki. In a letter to historian Herries Beattie , Chalmers recorded his account of

20276-476: Was by far the most economic way to get the region's produce to Dunedin and was a boon for the runholders of Waenga Station and the orchardists in the gorge. With the coming of the Clyde dam, the Cromwell-Clyde railway was closed in 1980. When the dam itself was completed, the line to Clyde had little other traffic and the section from Middlemarch to Clyde was closed on 30 April 1990. The line beyond Middlemarch

20424-473: Was caused by the melting of glaciers. The most recent age of the Holocene is the present Meghalayan, which began with extreme drought that lasted around 200 years. The word Holocene was formed from two Ancient Greek words. Hólos ( ὅλος ) is the Greek word for "whole". "Cene" comes from the Greek word kainós ( καινός ), meaning "new". The concept is that this epoch is "entirely new". The suffix '-cene'

20572-448: Was closely followed in the mid 1850s by early pastoralists and runholders searching for sheep grazing land in the vast, trackless interior. It was only after surveyor John Turnbull Thomson and Alexander Garvie lead a reconnaissance survey of the region in 1857-58, that pastoralists moved into the area in earnest; within a year of Turnbull's survey some 4 × 10 ^ acres (1.6 × 10 ^  ha) had been applied for. The Cromwell Gorge

20720-513: Was coeval with a major humidification before being terminated by a major drought and warming at the end of that interval. During the Early Holocene, relative sea level rose in the Bahia region, causing a landward expansion of mangroves. During the Late Holocene, the mangroves declined as sea level dropped and freshwater supply increased. In the Santa Catarina region, the maximum sea level highstand

20868-480: Was completed in 1990, however it was not commissioned until 1992 at a total cost of $ 955M NZD (September 1987). The cost of the dam was made up of Ministry of Works and Development civil works for Clyde: $ 591 million; Electricorp works, Clyde: $ 175 million; road realignment works: $ 100 million; property compensation: $ 24 million; Cromwell Township: $ 65 million. The roadworks figures would later significantly inflate due to costs incurred during landslide stabilisation in

21016-592: Was confined to the area immediately south of the STF, and is correlated with reduced westerly winds near New Zealand. Since 7,100 BP, New Zealand experienced 53 cyclones similar in magnitude to Cyclone Bola . Evidence from the Galápagos Islands shows that the El Niño–Southern Oscillation (ENSO) was significantly weaker during the Middle Holocene, but that the strength of ENSO became moderate to high over

21164-603: Was exceptionally severe and resulted in unseasonably low-levels of the Clutha River. Horatio Hartley and Christopher Reilly worked the sides of the Cromwell Gorge for three months until they were forced to take the huge hoard of gold they had secretly amassed to the Chief Gold Receiver in Dunedin in August 1862. Hartley and Reilly's discovery caused great excitement as they deposited some 87 lb (1,390 oz) of gold, sparking

21312-460: Was experienced during the MWP. A warming of +1 degree Celsius occurs 5–40 times more frequently in modern years than during the MWP. The major forcing during the MWP was due to greater solar activity, which led to heterogeneity compared to the greenhouse gas forcing of modern years that leads to more homogeneous warming. This was followed by the Little Ice Age (LIA) from the 13th or 14th century to

21460-568: Was lifted during 1991, and the track-bed as far as Clyde was handed over to the Department of Conservation in 1993, becoming the Otago Central Rail Trail . Orchardists moved to the gorge because of its frost-free springs. Orchards, grown on both sides of the Clutha River, primarily produced stone fruits (particularly apricots, cherries, nectarines, peaches, plums) as well as a number of varieties of apples and pears. The Cromwell Gorge had

21608-417: Was made more problematic due to the manner by which they were initially invited to New Zealand; the Chinese regarded themselves as temporary visitors seeking gold. As such they tended to have little interaction with Europeans, and the importance of their place in Central Otago's history has often been overlooked. A railway to Cromwell had been proposed at least as early as 1877, although it was intended to link

21756-443: Was recognised from the outset: Any further Clutha Valley development poses a very complex problem as there are considerable areas of better lands, orchards, allied industries, communication routes, closer settlement, and whole townships or effects on townships and local bodies to be taken into account. Protests that the dam would flood established orchards, the railway, State Highway 8 as well as parts of Cromwell were all ignored with

21904-410: Was the site of Central Otago's first gold rush into the region's interior and followed soon after the discovery of gold at Gabriel's Gully near Lawrence . The initial rush to the gorge, referred to as the Dunstan goldfield, began on 16 August 1862 following an announcement in the Otago Daily Times that two men, Hartley and Reilly , had discovered 87 lb (1044 t oz) of gold. The winter of 1862

#974025