105-629: Armidale is a city in the Northern Tablelands , New South Wales , Australia. Armidale had a population of 23,967 as of the 2021 census. It is the administrative centre for the Northern Tablelands region. It is approximately halfway between Sydney and Brisbane at the junction of the New England Highway and Waterfall Way . Armidale is a rural university town , home to the University of New England (UNE). Before
210-408: A distinctive composition or mode or origin. Special names still in wide use include amphibolite, greenschist , phyllite, marble, serpentinite , eclogite, migmatite , skarn , granulite , mylonite, and slate. The basic classification can be supplemented by terms describing mineral content or texture. For example, a metabasalt showing weak schistosity might be described as a gneissic metabasalt, and
315-455: A distinctive layering called foliation (derived from the Latin word folia , meaning "leaves"). Foliation develops when a rock is being shortened along one axis during recrystallization. This causes crystals of platy minerals, such as mica and chlorite , to become rotated such that their short axes are parallel to the direction of shortening. This results in a banded, or foliated, rock, with
420-731: A great diversity of plants and fauna, with many thousands of animals, birds and plants in the region. Black sallee ( Eucalyptus stellulata ), Blakely's red gum ( Eucalyptus blakelyi ), broadleaved New England stringybark ( Eucalyptus caliginosa ), wattles ( Acacias ), native apples ( Angophora floribunda ), manna gum ( Eucalyptus viminalis ), New England blackbutt ( Eucalyptus andrewsii ), New England peppermint ( Eucalyptus nova-anglica ), ribbon gum ( Eucalyptus nobilis ), silvertop stringybark ( Eucalyptus laevopinea ), snow gum ( Eucalyptus pauciflora ), river oak ( Casuarina cunninghamiana , stringybark ( Eucalyptus caliginosa ) and yellow box ( Eucalyptus melliodora ) trees are common across
525-637: A large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture . They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distortion. Metamorphic rock can be formed locally when rock
630-469: A marble will not be identical with the amphibolite facies of a pelite. However, the facies are defined such that metamorphic rock with as broad a range of compositions as is practical can be assigned to a particular facies. The present definition of metamorphic facies is largely based on the work of the Finnish geologist, Pentti Eskola , with refinements based on subsequent experimental work. Eskola drew upon
735-533: A metamorphic rock to be classified in this manner, the protolith should be identifiable from the characteristics of the metamorphic rock itself, and not inferred from other information. Under the British Geological Survey's classification system, if all that can be determined about the protolith is its general type, such as sedimentary or volcanic, the classification is based on the mineral mode (the volume percentages of different minerals in
840-623: A number of heritage-listed sites, including: The following notable people were either born in, currently live in or previously resided in Armidale [REDACTED] Armidale travel guide from Wikivoyage Northern Tablelands The Northern Tablelands , also known as the New England Tableland , is a plateau and a region of the Great Dividing Range in northern New South Wales , Australia . It includes
945-413: A pelite containing abundant staurolite might be described as a staurolite pelite. [REDACTED] A metamorphic facies is a set of distinctive assemblages of minerals that are found in metamorphic rock that formed under a specific combination of pressure and temperature. The particular assemblage is somewhat dependent on the composition of that protolith, so that (for example) the amphibolite facies of
1050-516: A process called metamorphism . The original rock ( protolith ) is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure of 100 megapascals (1,000 bar ) or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous , sedimentary , or existing metamorphic rock. Metamorphic rocks make up
1155-519: A relatively mild grade of metamorphism, at temperatures of 350–500 °C (662–932 °F) and pressures of 200–500 MPa (2,000–5,000 bar). They can be divided into a lower group of metabasalts, including rare meta komatiites ; a middle group of meta-intermediate-rock and meta-felsic-rock; and an upper group of metasedimentary rock. The greenstone belts are surrounded by high-grade gneiss terrains showing highly deformed low-pressure, high-temperature (over 500 °C (932 °F)) metamorphism to
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#17327732960411260-454: A street parade, stalls and celebrations throughout the city. It is a regular part of the city's attractions, often promoting Armidale's diverse culture (for instance, posters set up by council attempt to attract tourists with the motto "Foodies Thrive in Armidale") and autumn colours. During May the annual New England Wool Expo is staged to display wool fashions, handicrafts, demonstrations, shearing competitions, yard dog trials and demonstrations,
1365-597: A strong supporter of the movement, successfully lobbied for Armidale to have the second teachers' college in New South Wales, and later a university , positioning the town as a potential state capital. Armidale is on the banks of Dumaresq Creek, in the Northern Tablelands in the New England region about midway between Sydney and Brisbane at an altitude (980 m AHD ) ranging from 970 metres at
1470-410: A variety of metamorphic facies. Where subduction is taking place, the basalt of the subducting slab is metamorphosed to high-pressure metamorphic facies. It initially undergoes low-grade metamorphism to metabasalt of the zeolite and prehnite-pumpellyite facies , but as the basalt subducts to greater depths, it is metamorphosed to the blueschist facies and then the eclogite facies . Metamorphism to
1575-408: A wide range of courses, and introduced a number of new courses in 2008, including a five-year Bachelor of Medical Science and Doctor of Medicine program as part of a joint medical program with the University of Newcastle . The university is built around the historic mansion Booloominbah , which is now used for administration and houses a restaurant. UNE is one of the city's main employers. Armidale
1680-620: A wool bale rolling competition and other activities. According to the 2021 census , there were 23,967 people in the Armidale significant urban area. Armidale is home to a Êzidî community of approximately 650. The Armidale railway station is on the Main North railway line and is served by daily passenger trains to and from Sydney. Armidale's airport has five daily scheduled flights to and from Sydney with Qantaslink . Link Airways operates scheduled services between Armidale and Brisbane. Armidale Airport , at 1,084 metres (3,556 ft),
1785-417: Is a great variety of metamorphic rock types. In general, if the protolith of a metamorphic rock can be determined, the rock is described by adding the prefix meta- to the protolith rock name. For example, if the protolith is known to be basalt , the rock will be described as a metabasalt. Likewise, a metamorphic rock whose protolith is known to be a conglomerate will be described as a metaconglomerate . For
1890-471: Is a high rainfall region with averages ranging from 650 mm on the western slopes to over 1,200 mm on the east of the range. About 60% of this rainfall occurs during the summer months. Australian Aboriginals have lived on the tablelands for tens of thousands of years. Prior to colonisation there were several language groups in the region, included the Anaiwan language. The indigenous population of
1995-458: Is a major regional retail centre, housing three shopping malls : Armidale has a pedestrian mall which stretches over three blocks of Beardy Street in the centre of city. It features many shops and cafés with outdoor eating areas along with some notable architecture, including Tattersalls Hotel, built in the Art Deco style during the 1930s; Armidale Courthouse ; the city's main post office ;
2100-530: Is also prized for building construction and as a medium for sculpture. On the other hand, schist bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness. Metamorphic rocks form one of the three great divisions of rock types. They are distinguished from igneous rocks , which form from molten magma , and sedimentary rocks , which form from sediments eroded from existing rock or precipitated chemically from bodies of water. Metamorphic rocks are formed when existing rock
2205-543: Is an option to get around Armidale. A cycleway exists from the University of New England through the city to the residential areas on the eastern side of city. This cycleway snakes back towards Ben Venue School . The passage through the city provides easy access for cyclists to the shopping centres. Bicycle racks are in strategic locations around the city centre, including at The Armidale Food Emporium, The Armidale Plaza, and Centro Armidale. Places are also provided outside
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#17327732960412310-426: Is called a paired metamorphic belt . The main islands of Japan show three distinct paired metamorphic belts, corresponding to different episodes of subduction. Metamorphic rock is also exposed in metamorphic core complexes , which form in region of crustal extension. They are characterized by low-angle faulting that exposes domes of middle or lower crust metamorphic rock. These were first recognized and studied in
2415-464: Is dominated by metamorphic rock that has reached the amphibolite facies. Within the upper crust, which is the only part of the Earth's crust geologists can directly sample, metamorphic rock forms only from processes that can occur at shallow depth. These are contact (thermal) metamorphism , dynamic (cataclastic) metamorphism , hydrothermal metamorphism , and impact metamorphism . These processes are relatively local in occurrence and usually reach only
2520-476: Is formed as tectonic plates move apart. Hydrothermal metamorphism is extensive here. This is characterized by metasomatism by hot fluids circulating through the rock. This produces metamorphic rock of the greenschist facies. The metamorphic rock, serpentinite , is particularly characteristic of these settings, and represents chemical transformation of olivine and pyroxene in ultramafic rock to serpentine group minerals. Contact metamorphism takes place when magma
2625-464: Is heated by the intrusion of hot molten rock called magma from the Earth's interior. The study of metamorphic rocks (now exposed at the Earth's surface following erosion and uplift) provides information about the temperatures and pressures that occur at great depths within the Earth's crust. Some examples of metamorphic rocks are gneiss , slate , marble , schist , and quartzite . Slate and quartzite tiles are used in building construction. Marble
2730-403: Is injected into the surrounding solid rock ( country rock ). The changes that occur are greatest wherever the magma comes into contact with the rock because the temperatures are highest at this boundary and decrease with distance from it. Around the igneous rock that forms from the cooling magma is a metamorphosed zone called a contact aureole . Aureoles may show all degrees of metamorphism from
2835-405: Is known as burial metamorphism . This tends to produce low-grade metamorphic rock. Much more common is metamorphic rock formed during the collision process itself. The collision of plates causes high temperatures, pressures and deformation in the rocks along these belts. Metamorphic rock formed in these settings tends to shown well-developed schistosity. Metamorphic rock of orogenic belts shows
2940-506: Is sufficiently hard and dense that it is difficult to quarry. However, some quartzite is used as dimension stone , often as slabs for flooring, walls, or stairsteps. About 6% of crushed stone, used mostly for road aggregate, is quartzite. Marble is also prized for building construction and as a medium for sculpture. Schistose bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness. A hazard may exist even in undisturbed terrain. On August 17, 1959,
3045-419: Is the highest licensed airport in New South Wales. The city is linked further north by daily coach to Tenterfield provided by NSW TrainLink . Other bus companies such as Greyhound also provide numerous daily services. Local city services are provided on six different routes by Edwards Coaches and Armidale is serviced by 16 taxis . Although the hills to the north and the south can be a challenge, cycling
3150-643: Is the main vegetation community in the region. The eastern escarpment of the Tableland has spectacular gorges, rainforests and waterfalls, protected in more than 25 National Parks , with three of them listed as World Heritage Areas by UNESCO and forming part of the Central Eastern Rainforest Reserves (CERRA). Werrikimbe National Park and Oxley Wild Rivers National Park , one of the largest national parks in NSW are accessible from
3255-553: Is transformed physically or chemically at elevated temperature, without actually melting to any great degree. The importance of heating in the formation of metamorphic rock was first noted by the pioneering Scottish naturalist, James Hutton , who is often described as the father of modern geology. Hutton wrote in 1795 that some rock beds of the Scottish Highlands had originally been sedimentary rock but had been transformed by great heat. Hutton also speculated that pressure
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3360-400: Is uncertain. Special classifications exist for metamorphic rocks with a volcaniclastic protolith or formed along a fault or through hydrothermal circulation . A few special names are used for rocks of unknown protolith but known modal composition, such as marble, eclogite , or amphibolite . Special names may also be applied more generally to rocks dominated by a single mineral, or with
3465-426: Is used only when very little else is known about the rock that would allow a more definite classification. Textural classifications may be prefixed to indicate a sedimentary protolith ( para- , such as paraschist) or igneous protolith ( ortho- , such as orthogneiss). When nothing is known about the protolith, the textural name is used without a prefix. For example, a schist is a rock with schistose texture whose protolith
3570-475: Is usually devoid of schistosity and forms a tough, equigranular rock. If the rock was originally banded or foliated (as, for example, a laminated sandstone or a foliated calc- schist ) this character may not be obliterated, and a banded hornfels is the product. Contact metamorphism close to the surface produces distinctive low-pressure metamorphic minerals, such as spinel , andalusite, vesuvianite , or wollastonite . Similar changes may be induced in shales by
3675-470: Is very low in silica) to metafelsic-rock (with a high silica content). Where the mineral mode cannot be determined, as is often the case when rock is first examined in the field , then classification must be based on texture. The textural types are: A hornfels is a granofels that is known to result from contact metamorphism. A slate is a fine-grained metamorphic rock that easily splits into thin plates but shows no obvious compositional layering. The term
3780-570: The Basin and Range Province of southwestern North America, but are also found in southern Aegean Sea , in the D'Entrecasteaux Islands , and in other areas of extension. Continental shields are regions of exposed ancient rock that make up the stable cores of continents. The rock exposed in the oldest regions of shields, which is of Archean age (over 2500 million years old), mostly belong to granite-greenstone belts. The greenstone belts contain metavolcanic and metasedimentary rock that has undergone
3885-609: The Gara River below the Blue Hole at Castle Doyle . The nearby town of Uralla holds the grave of the famous Captain Thunderbolt – outlaw Fred Ward – who caused trouble in the area in the 1860s. As with Ned Kelly , the locals have adopted him as a larrikin hero and make the most of him as a tourist attraction. Armidale became a municipality in 1863 and was proclaimed a city in 1885. Although it does not lie between
3990-750: The Gwydir , Namoi and Macintyre river systems of the Murray-Darling River Basin . The only major water storage dam on the Northern Tablelands is Copeton Dam on the Gwydir River near Inverell. The high elevation of the tablelands means cool summers (rarely over 32 °C) but winters are cold with occasional snowfalls and many frosty mornings. Winter minimums can go as low as -10 °C around Armidale , Guyra , Woolbrook and Walcha regions during frosty mornings, but this usually results in clear sunny days. The Northern Tablelands
4095-555: The Oxley Highway east of Walcha. The Oxley Wild Rivers National Park is also accessible via Waterfall Way east of Armidale and south of Hillgrove . Access to the World Heritage listed New England National Park is also from Waterfall Way. The coastal flowing Clarence , Macleay and Manning , rivers have their headwaters on eastern escarpment of the Tableland. The inland flowing rivers have their confluence with
4200-450: The atoms and ions in solid crystals to migrate, thus reorganizing the crystals, while high pressures cause solution of the crystals within the rock at their point of contact. Metamorphic rocks are characterized by their distinctive mineral composition and texture. Because every mineral is stable only within certain limits, the presence of certain minerals in metamorphic rocks indicates the approximate temperatures and pressures at which
4305-402: The crystallization of igneous rocks. They are stable at high temperatures and pressures and may remain chemically unchanged during the metamorphic process. Metamorphic rocks are typically more coarsely crystalline than the protolith from which they formed. Atoms in the interior of a crystal are surrounded by a stable arrangement of neighboring atoms. This is partially missing at the surface of
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4410-446: The "New England" moniker and the autumn colours are notable features of the city. Summers are characterised by warm to very warm days followed almost always by cool, sometimes cold, nights. Thunderstorms often produce heavy falls of rain and occasionally hail in the afternoons and early evenings, also bringing a sudden drop in temperature. Unlike nearby coastal areas, Armidale does not usually experience high humidity levels making most of
4515-696: The Armidale Dumeresq War Memorial Library, and at either end of the Mall. A maze of marked cycleways on the shoulder of the roads in the city's southern residential areas allows cyclists to safely ride on the roads. There are also separate cycleways from the Armidale Arboretum along Kellys Plains Road to the south and from the north of the city along Rockvale Road to the Armidale State Forest (known as
4620-911: The Armidale Rams RLFC, and the Narwan Eels, a club with a distinct Indigenous influence. The Rams are based at Rugby League Park on Dumaresq St in Central Armidale, whilst the Eels are based at Newling Oval on the southern outskirts of the city. Other sports teams include the UNE New England Nomads (University AFL team) and various soccer teams in the local SportUNE League. The city is serviced by one local newspaper, many radio stations including four local outlets, and all major television stations. Subscription Television services are provided by Foxtel . Armidale has
4725-505: The British colonial settlement of New South Wales, the indigenous Anaiwan tribe occupied the area that encompasses current day Armidale. British pastoralists first entered the region in the early 1830s, following the earlier exploration of the area by John Oxley . Oxley recommended the region for grazing, and soon squatters established large leaseholds in the locality. Armidale was initially founded in 1839 by George James MacDonald who
4830-1071: The New England Range, the narrow highlands area of the New England region, stretching from the Moonbi Range in the south to the Queensland border in the north. The region corresponds generally to the Bureau of Meteorology forecast area for the Northern Tablelands which in this case includes Inverell although it is significantly lower in elevation. These tablelands are the largest highland area in Australia, covering approximately 18,197 square kilometres. There are widespread high points over 1,000 metres including The Brothers (1,508m), Ben Lomond (1,505m), Mount Rumbee (1,503m), Point Lookout (1,564m), Campoompeta (1,510m), Mount Spirabo (1,492m), Mount Mitchell (1,475m), Chandler's Peak (1,471m), Mount Grundy (1,462m), Mount Bajimba (1,448 m) and
4935-510: The Northern Tablelands include the brush-tailed rock-wallaby ( Petrogale penicillata ) which lives in isolated sections of the Oxley Wild Rivers National Park . The Bundarra-Barraba Important Bird Area is one of only three breeding areas in New South Wales for the endangered regent honeyeater . Metamorphosed Metamorphic rocks arise from the transformation of existing rock to new types of rock in
5040-697: The Northern Tablelands which has a total of about 792,000 beef cattle. The region has approximately 3.1 million sheep. Areas around Armidale , Uralla and Walcha are noted for their superfine wool production. The Northern Tablelands has been declared an Ovine Johne's disease (OJD) Exclusion Area (EA), under the Stock Diseases Act 1923. Walcha is the site of a large modern dairy farm. Guyra produces prime lambs, potatoes , tulips and glasshouse tomatoes . Apples, pears and other stone fruit are grown at Kentucky and Arding. Pigs, bees, and more recently vineyards also contribute to agricultural production on
5145-625: The Northern Tablelands. Bolivia Hill and the adjacent nature reserve are the only recorded locations of the endangered Bolivia Hill boronia ( Boronia boliviensis ) and the shrub Pimelea venosa. Some rare Hillgrove gum trees ( Eucalyptus michaeliana ) may be seen growing along the Long Point Road and the Big Lease, Oxley Wild Rivers National Park . These trees have a distinctive, mottled, greenish trunk with peeling yellow-brown bark. Weeds are an increasing problem across much of
5250-800: The Pine Forest by locals). The city is home to a large number of education facilities, including the Armidale School (1894), New England Girls' School (1895), Presbyterian Ladies' College (PLC Armidale) (1887), and the Armidale Waldorf School (1985), schools of the Australian independent education sector. O'Connor Catholic College (1975) and St Mary's Primary School are systemic Catholic schools . Armidale High School (1911) and Duval High School (1972) were government-funded secondary schools until their closing at
5355-418: The University of New England in 2007 found winter woodsmoke causes 8.8 additional visits per day to GPs in Armidale for respiratory complaints, i.e., about 750 additional visits per year. Another peer-reviewed study estimated the use of wood heaters in Armidale was responsible for about 11.5 premature deaths per year with estimated annual health cost of $ 14.95 million – about $ 4720 per year for every woodheater in
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#17327732960415460-482: The amphibolite or granulite facies. These form most of the exposed rock in Archean cratons. The granite-greenstone belts are intruded by a distinctive group of granitic rocks called the tonalite - trondhjemite - granodiorite or TTG suite. These are the most voluminous rocks in the craton and may represent an important early phase in the formation of continental crust. Mid-ocean ridges are where new oceanic crust
5565-725: The area from Newcastle to the Queensland border. Thunderbolt was shot dead by Constable Walker in May 1870 in Kentucky Creek after a long chase on horseback. His grave is in the town of Uralla, NSW. The Northern Tablelands includes the towns and Local Government Areas of Armidale , Glen Innes , Guyra , Tenterfield , Walcha , the south-eastern portion of the Inverell Shire and a small part of Tamworth Regional Council area. The University of New England at Armidale
5670-404: The bands showing the colors of the minerals that formed them. Foliated rock often develops planes of cleavage . Slate is an example of a foliated metamorphic rock, originating from shale , and it typically shows well-developed cleavage that allows slate to be split into thin plates. The type of foliation that develops depends on the metamorphic grade. For instance, starting with a mudstone ,
5775-420: The bulk composition of a rock. Hot fluids circulating through pore space in the rock can dissolve existing minerals and precipitate new minerals. Dissolved substances are transported out of the rock by the fluids while new substances are brought in by fresh fluids. This can obviously change the mineral makeup of the rock. However, changes in the mineral composition can take place even when the bulk composition of
5880-399: The burning of coal seams. This produces a rock type named clinker . There is also a tendency for metasomatism between the igneous magma and sedimentary country rock, whereby the chemicals in each are exchanged or introduced into the other. In that case, hybrid rocks called skarn arise. Dynamic (cataclastic) metamorphism takes place locally along faults . Here intense shearing of
5985-435: The circulation of fluids through buried rock, to the list of processes that help bring about metamorphism. However, metamorphism can take place without metasomatism ( isochemical metamorphism ) or at depths of just a few hundred meters where pressures are relatively low (for example, in contact metamorphism ). Metamorphic processes change the texture or mineral composition of the metamorphosed rock. Metasomatism can change
6090-439: The city. Armidale has a subtropical highland climate ( Köppen : Cfb ). Armidale's elevation gives it a milder climate than most of northern New South Wales, but the summers are still very warm. Winters are long and cool, with many frosty nights. Snowfall is somewhat rare, on average only one day in every three years. In Armidale, the presence of four distinct seasons makes it climatically unlike much of inland Australia; hence,
6195-427: The collision of tectonic plates at convergent boundaries . Here formerly deeply buried rock has been brought to the surface by uplift and erosion. The metamorphic rock exposed in orogenic belts may have been metamorphosed simply by being at great depths below the Earth's surface, subjected to high temperatures and the great pressure caused by the immense weight of the rock layers above. This kind of regional metamorphism
6300-491: The contact area to unmetamorphosed (unchanged) country rock some distance away. The formation of important ore minerals may occur by the process of metasomatism at or near the contact zone. Contact aureoles around large plutons may be as much as several kilometers wide. The term hornfels is often used by geologists to signify those fine grained, compact, non-foliated products of contact metamorphism. The contact aureole typically shows little deformation, and so hornfels
6405-565: The creation of one-way streets . The most popular sport in Armidale is rugby union . The city has four teams in the New England Rugby Union : Armidale Blues, Barbarians, Robb College, St. Albert's College, the latter two of which are made up of primarily university students staying on residence at the respective colleges. A close second in popularity in the city is rugby league . Armidale has two teams competing in Group 19 ,
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#17327732960416510-612: The crystal, producing a surface energy that makes the surface thermodynamically unstable. Recrystallization to coarser crystals reduces the surface area and so minimizes the surface energy. Although grain coarsening is a common result of metamorphism, rock that is intensely deformed may eliminate strain energy by recrystallizing as a fine-grained rock called mylonite . Certain kinds of rock, such as those rich in quartz, carbonate minerals , or olivine, are particularly prone to form mylonites, while feldspar and garnet are resistant to mylonitization. Many kinds of metamorphic rocks show
6615-423: The eclogite facies releases a great deal of water vapor from the rock, which drives volcanism in the overlying volcanic arc . Eclogite is also significantly denser than blueschist, which drives further subduction of the slab deep into the Earth's mantle . Metabasalt and blueschist may be preserved in blueschist metamorphic belts formed by collisions between continents. They may also be preserved by obduction onto
6720-651: The end of 2018. In 2019, the two schools were combined into one in the form of Armidale Secondary College , which is located on what was the Armidale High School campus. It was previously located on the Duval High School campus as a placeholder while the Armidale High campus was partially demolished. Approximately 27% of Armidale's total population is in the 10–24-year age group, compared with an equivalent NSW figure of 18%. The university
6825-437: The following sequence develops with increasing temperature: The mudstone is first converted to slate, which is a very fine-grained, foliated metamorphic rock, characteristic of very low grade metamorphism. Slate in turn is converted to phyllite , which is fine-grained and found in areas of low grade metamorphism. Schist is medium to coarse-grained and found in areas of medium grade metamorphism. High-grade metamorphism transforms
6930-677: The former Commonwealth Bank and the New England Hotel. The mall was opened in 1973 and was the first of its kind in regional Australia. Armidale Dumaresq Council has been undertaking major upgrades to the mall since 2003 as part of the Armidale CBD Streetscape Design Project which aims at easing traffic in the city centre by creating an emphasis on the "ring road" around the CBD with the assistance of signage , elevation of roads using paving and
7035-469: The founding settlers who had beards. The court house was built in the 1850s and is still a prominent feature of the central district. Much of the rest of the city is residential. The Australian Wool Fashion Awards, which showcases the use of Merino wool by fashion designers, are hosted by Armidale in March each year. The Autumn Festival is a popular annual event of April in Armidale. The festival features
7140-577: The gold mining here after 1900. Captain Thunderbolt the famous bushranger (Frederick Wordsworth Ward, 1836–1870) who escaped from Cockatoo Island came to the Northern Tablelands, where he robbed properties, mail coaches and hotels in the region. In 1866 the Colonial Secretary's Office posted a reward of £100 for his capture, which was raised to £200 by mid-1867 and £400 in December 1869. Many stories have been told his bushranging deeds in
7245-631: The ground; at the Tree Group Nursery station a reading as low as −11.2 °C or 11.8 °F was record on 30 June 2010, whilst the older station at Radio 2AD recorded −9.3 °C or 15.3 °F on 15 July 1970. These cold frosty mornings are usually followed by sunny days. Day temperatures may make it as high as 16 °C or 60.8 °F, but sometimes may not climb beyond 10 °C or 50 °F. These are typical Northern Tablelands winter days with westerly winds, bleak grey clouds, and showers of rain and very occasionally snow. Rainfall during
7350-529: The highest point at Round Mountain is 1,584 metres above sea level. The now closed railway station at Ben Lomond , was the highest railway station in Australia. The formation of the Great Dividing Range has resulted in a wide variety of soil types being located on the Northern Tablelands. Here soils are mostly derived from basaltic rocks, granite rocks, trap rock or alluvials along creeks and rivers. The New England Peppermint Grassy Woodland
7455-449: The identical composition, Al 2 SiO 5 . Likewise, forsterite is stable over a broad range of pressure and temperature in marble , but is converted to pyroxene at elevated pressure and temperature in more silicate-rich rock containing plagioclase , with which the forsterite reacts chemically. Many complex high-temperature reactions may take place between minerals without them melting, and each mineral assemblage produced indicates
7560-437: The low-pressure facies, such as the hornfels and sanidinite facies . Most metamorphic rock is formed by regional metamorphism in the middle and lower crust, where the rock reaches the higher-pressure metamorphic facies. This rock is found at the surface only where extensive uplift and erosion has exhumed rock that was formerly much deeper in the crust. Metamorphic rock is extensively exposed in orogenic belts produced by
7665-488: The original St Peter's Church, was designed by the Canadian architect John Horbury Hunt , who also designed Booloominbah at the University of New England . St Peter's Cathedral opened for worship in 1875 and the tower was added in 1938. The Catholic Cathedral of St Mary and St Joseph was dedicated on 12 December 1919. The city centre is laid out in a grid of streets. The main street is called Beardy Street, named for two of
7770-460: The overriding plate as part of ophiolites . Eclogites are occasionally found at sites of continental collision, where the subducted rock is rapidly brought back to the surface, before it can be converted to the granulite facies in the hot upper mantle. Many samples of eclogite are xenoliths brought to the surface by volcanic activity. Many orogenic belts contain higher-temperature, lower-pressure metamorphic belts. These may form through heating of
7875-637: The region. Foxes and rabbits are the most significant vertebrae pests of the tablelands. Eighteen endangered fauna species, found on the Northern Tableland, have been listed in the schedules of the Threatened Species Conservation Act. The endangered Hastings River mouse ( Pseudomys oralis ) is restricted in distribution to the upland open forests and woodlands around Werrikimbe National Park and south-east Queensland. Other endangered species that may be seen on
7980-475: The rock by ascending magmas of volcanic arcs, but on a regional scale. Deformation and crustal thickening in an orogenic belt may also produce these kinds of metamorphic rocks. These rocks reach the greenschist , amphibolite, or granulite facies and are the most common of metamorphic rocks produced by regional metamorphosis. The association of an outer high-pressure, low-temperature metamorphic zone with an inner zone of low-pressure, high-temperature metamorphic rocks
8085-421: The rock does not change. This is possible because all minerals are stable only within certain limits of temperature, pressure, and chemical environment. For example, at atmospheric pressure, the mineral kyanite transforms to andalusite at a temperature of about 190 °C (374 °F). Andalusite, in turn, transforms to sillimanite when the temperature reaches about 800 °C (1,470 °F). All three have
8190-423: The rock to gneiss , which is coarse to very coarse-grained. Rocks that were subjected to uniform pressure from all sides, or those that lack minerals with distinctive growth habits, will not be foliated. Marble lacks platy minerals and is generally not foliated, which allows its use as a material for sculpture and architecture. Metamorphic rocks are one of the three great divisions of all rock types, and so there
8295-495: The rock typically forms mylonites. Impact metamorphism is unlike other forms of metamorphism in that it takes place during impact events by extraterrestrial bodies. It produces rare ultrahigh pressure metamorphic minerals, such as coesite and stishovite . Coesite is rarely found in eclogite brought to the surface in kimberlite pipes , but the presence of stishovite is unique to impact structures. Slate tiles are used in construction, particularly as roof shingle. Quartzite
8400-407: The rock underwent metamorphism. These minerals are known as index minerals . Examples include sillimanite , kyanite , staurolite , andalusite , and some garnet . Other minerals, such as olivines , pyroxenes , hornblende , micas , feldspars , and quartz , may be found in metamorphic rocks but are not necessarily the result of the process of metamorphism. These minerals can also form during
8505-486: The rock). Metasedimentary rocks are divided into carbonate-rich rock (metacarbonates or calcsilicate-rocks) or carbonate-poor rocks, and the latter are further classified by the relative abundance of mica in their composition. This ranges from low-mica psammite through semipelite to high-mica pelite . Psammites composed mostly of quartz are classified as quartzite. Metaigneous rocks are classified similarly to igneous rocks, by silica content, from meta-ultramafic-rock (which
8610-406: The sedimentary rock limestone and chalk change into larger crystals in the metamorphic rock marble . In metamorphosed sandstone, recrystallization of the original quartz sand grains results in very compact quartzite, also known as metaquartzite, in which the often larger quartz crystals are interlocked. Both high temperatures and pressures contribute to recrystallization. High temperatures allow
8715-512: The soil substrates. Those areas away from the deep gorge country tend to display gently undulating terrain mainly used for pastures and where granites occur the areas are usually covered in bushland. The area contains a number of places of outstanding natural beauty and scientific interest as well as several World Heritage national parks including the New England National Park and the Oxley Wild Rivers National Park . To
8820-486: The southern half of the Tablelands between the 1830s and 1860s. In 1852 gold was discovered at Rocky River and by 1856 there were 5,000 miners operating there. Gold was discovered at Bakers Creek, Hillgrove in 1857 but it was not until the late 1880s that the recorded population rose to 2,274 and later to almost 3,000 in about 1898. The difficulties and expense of the deep underground mine workings eventually reduced
8925-446: The start of summer. Armidale has been prone to severe hailstorms and experienced three such storms over the ten-year period from 1996 to 2006. On 29 September 1996 hail of up to 80 millimetres (3.1 in) in diameter and southerly winds of up to 150 kilometres per hour (93 mph) were reported at the airport weather station. The area was declared a disaster zone and State Emergency Service crews were brought in from across
9030-526: The state. Damage was estimated to be in excess of A$ 200 million. On 1 January 2000 many homes were damaged by extreme weather conditions which brought large hail stones, strong winds and flash flooding . On 21 December 2006 hail stones, high winds and flash flooding damaged more than 1,000 homes and destroyed the Armidale Livestock Exhibition Centre which collapsed entirely under the weight of accumulated hail. The city
9135-469: The summer days quite comfortable. Temperatures exceed 30 °C or 86 °F on an average of 13 afternoons per year, but rarely reach higher than 35 °C or 95 °F. The highest temperature recorded at Armidale Airport was 37.1 °C (98.8 °F), recorded in February 2017. As the leaves turn yellow and fall, day temperatures are mostly still warm, particularly in March and April. Days are sunny,
9240-498: The tablelands has been estimated to be 1,100 to 1,200 at the time of colonisation, but was reduced to perhaps 400 by the 1890s. Walcha was explored in 1818 by John Oxley who ascended the range near Limbri . In 1832 Hamilton Collins Semphill, a settler from Belltrees on the Hunter River , formed a station in the upper Apsley River valley and named it Wolka (Walcha) from the local Aboriginal language. Edward Gostwych Cory, who
9345-424: The tablelands. During 2008 nine local government areas in the Northern Tablelands recorded a 12 to 35 per cent growth in property values over the last 12 months and a 13 to 22 per cent rise over the last five years according to a report from Australian Property Monitors. Gold and antimony are mined at Hillgrove . Lockheed Martin operates a satellite tracking dish near Uralla . The Northern Tablelands has
9450-404: The temperatures and pressures at the time of metamorphism. These reactions are possible because of rapid diffusion of atoms at elevated temperature. Pore fluid between mineral grains can be an important medium through which atoms are exchanged. The change in the particle size of the rock during the process of metamorphism is called recrystallization . For instance, the small calcite crystals in
9555-452: The thunderstorm season is over, and rain becomes more sporadic. Nights become colder, and residents often awake to a thick fog blanketing the Armidale valley, but by 9 am fogs have cleared to be followed by a bright sunny day. The year's first frosts usually occur in April, but they are not severe. Winters are cold; overnight temperatures drop below −5 °C or 23 °F with frost on
9660-544: The two major cities of Sydney and Melbourne, a site just to the south of Armidale was, in the early 1900s, considered as a potential site for Australia's federal capital. Some saw its northerly location as better suited to all three eastern mainland states, including Queensland. Later, particularly in the 1920s and 1930s, Armidale was one of the centres of separatist agitation by the New England New State Movement . Local politician, David Drummond ,
9765-451: The use of granulite as a classification for rock metamorphosed to the granulite facies. Instead, such rock will often be classified as a granofels. However, this approach is not universally accepted. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. The lower continental crust is mostly metamafic-rock and pelite which have reached the granulite facies . The middle continental crust
9870-482: The valley's floor to 1,110 metres above sea level at the crests of the hills. A short distance to the east of Armidale are heavily forested steep gorges dropping down to the eastern coastal plain. Large parts of the highlands are covered by Palaeozoic aged metamorphosed sedimentary rocks . Intruding into these meta-sediments are granite plutons which decompose to form sandy soil, slightly deficient in nutrients. There are also basalt flows which are more fertile for
9975-540: The west is Mount Yarrowyck Nature Reserve. The critically endangered New England Peppermint Grassy Woodland is the main vegetation community in the region. The coastal plain can be reached directly at Coffs Harbour via Waterfall Way to Dorrigo and Bellingen on the Bellinger River , a two-hour drive. During winter there is a problem with some air quality reduction caused by the use of solid fuel domestic wood heaters. A peer-reviewed study carried out by
10080-608: The winter months is not infrequent but is usually light. In spring temperatures are warmer, although occasional morning frosts still can continue well into October. September is usually a pleasantly mild but windy month, and by late October with increasing heat and humidity the thunderstorm season is starting with increasing rainfalls. The spring months produce the most variable weather of the year. A week of very warm sunny weather can be followed by several milder days with temperatures right back at winter levels before gradually warming up again. This cycle often repeats itself many times until
10185-511: The zonal schemes, based on index minerals, that were pioneered by the British geologist, George Barrow . The metamorphic facies is not usually considered when classifying metamorphic rock based on protolith, mineral mode, or texture. However, a few metamorphic facies produce rock of such distinctive character that the facies name is used for the rock when more precise classification is not possible. The chief examples are amphibolite and eclogite . The British Geological Survey strongly discourages
10290-467: Was declared a state of emergency by New South Wales Premier Morris Iemma the following day. On the night of 14 October 2021 at 10pm, an intense storm produced a tornado causing extensive damage. It tore away roofs and turned vehicles upside down. Armidale is a cathedral city, being the seat of the Anglican and Roman Catholic bishops of Armidale. St Peter's Anglican Cathedral, which replaced
10395-715: Was displaced from his runs by the Australian Agricultural Company , came over the Moonbi Range and settled at Gostwyck, near Uralla. Soon others followed, seeking new lands away from the influence of the Australian Agricultural Company, which dominated resources in the Hunter valley, and settled around the present Armidale district. In 1844 there were 454,193 sheep and 43,377 cattle grazing the tablelands region. Armidale
10500-527: Was established to provide a market and administration for the farms, but soon after gold was discovered at nearby Rocky River and Gara Gorges, and a gold rush ensued, enlarging the town rapidly in the 1850s. The gold mining settlement of Hillgrove about 40 km east of Armidale was supplied by electricity from Australia's first hydro-electric scheme, the Gara River Hydro-Electric Scheme , remains of which are still visible on
10605-428: Was founded in 1938, at first as a college of the University of Sydney , but then in its own right in 1954. The UNE contributes to Armidale's position as a city of culture and diversity, with a vibrant artistic and cultural element. The university has strong links to the rural community, and undertakes a lot of agricultural research. There is also a high-technology presence, as well as notable humanities teaching. UNE hosts
10710-673: Was founded in 1938, becoming the first Australian university established outside a capital city. This public university, with approximately 18,000 higher education students, is one of Australia's major providers of awards to off-campus students. The Northern Tablelands cover an area of approximately 3.12 million hectares including 2.11 million hectares occupied by some 2,300 agricultural establishments producing agricultural commodities valued at more than $ 320 million. Livestock production contributes approximately 90% of this annual income which comes from beef cattle, sheep and wool. Many beef cattle studs and commercial cattle breeders are located across
10815-419: Was important in metamorphism. This hypothesis was tested by his friend, James Hall , who sealed chalk into a makeshift pressure vessel constructed from a cannon barrel and heated it in an iron foundry furnace. Hall found that this produced a material strongly resembling marble , rather than the usual quicklime produced by heating of chalk in the open air. French geologists subsequently added metasomatism ,
10920-655: Was the Commissioner of Crown Lands and head of the local Border Police detachment in the New England district. MacDonald established his barracks on the site and named it after Armadale on the Isle of Skye in Scotland which was the ancestral home of the MacDonald clan. The James Barnet -designed heritage-listed Armidale Post Office opened on 1 April 1843. The town, which was surveyed in 1848 and gazetted in 1849,
11025-413: Was then gazetted as a town in 1849. Squatters soon settled the tablelands with their large sheep runs before Glen Innes and Tenterfield were surveyed in 1851. Armidale is the only city on the Tablelands and is the administrative centre for the Northern Tablelands region. Colonisation was often violently opposed by the indigenous peoples of New England. There were more than forty documented conflicts in
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