113-672: The Swan Coastal Plain in Western Australia is the geographic feature which contains the Swan River as it travels west to the Indian Ocean . The coastal plain continues well beyond the boundaries of the Swan River and its tributaries, as a geological and biological zone, one of Western Australia's Interim Biogeographic Regionalisation for Australia regions. It is also one of the distinct physiographic provinces of
226-548: A British army engineer who worked in Egypt prior to World War II . Bagnold investigated the physics of particles moving through the atmosphere and deposited by wind. He recognized two basic dune types, the crescentic dune, which he called " barchan ", and the linear dune, which he called longitudinal or "seif" (Arabic for "sword"). Bagnold developed a classification scheme that included small-scale ripples and sand sheets as well as various types of dunes. Bagnold's classification
339-406: A Y-junction with the fork directed upwind. They have a sharp sinuous or en echelon crest. They are thought to form from a bimodal seasonal wind pattern, with a weak wind season characterized by wind directed an at acute angle to the prevailing winds of the strong wind season. The strong wind season produces a barchan form and the weak wind season stretches this into the linear form. Another possibility
452-413: A boulder or an isolated patch of vegetation. Here the sand builds up to the angle of repose (the maximum stable slope angle), about 34 degrees, then begins sliding down the slip face of the patch. A sandfall is a sand shadow of a cliff or escarpment. Closely related to sand shadows are sand drifts . These form downwind of a gap between obstructions, due to the funneling effect of the obstructions on
565-683: A capacity of 23,200 cubic metres per day (146,000 barrels per day) until its closure in 2021, producing most of the state's petrol and diesel. Kwinana also hosts alumina and nickel processing plants, port facilities for grain and other bulk exports, and support industries for mining and petroleum such as heavy and light engineering, and metal fabrication. Shipbuilding (e.g. Austal ) and associated support industries are found at nearby Henderson , just north of Kwinana. Significant secondary industries include cement and building product manufacturing, flour milling, food processing, animal feed production, automotive body building and printing. Western Australia has
678-446: A change in the wind pattern about 3000 years ago. Complex dunes show Little lateral growth but strong vertical growth and are important sand sinks. Vegetated parabolic dunes are crescent-shaped, but the ends of the crescent point upwind, not downwind. They form from the interaction of vegetation patches with active sand sources, such as blowouts. The vegetation stabilizes the arms of the dune, and an elongated lake sometimes forms between
791-527: A comparative advantage in resource extraction and processing. As a consequence: In 2019 Western Australia's overseas exports accounted for 46% of the nation's total. The state's major export commodities included iron-ore, petroleum, gold, alumina , nickel, wheat, copper, lithium, chemicals and mineral sands. Western Australia is the world's largest iron-ore producer (34% of the world's total), and extracts 66% (6.9% of world production) of Australia's 306 tonnes (9.8 million troy ounces) of gold in 2022. It
904-531: A desert. Vegetation is effective at suppressing aeolian transport. Vegetation cover of as little as 15% is sufficient to eliminate most sand transport. The size of shore dunes is limited mostly by the amount of open space between vegetated areas. Aeolian transport from deserts plays an important role in ecosystems globally. For example, wind transports minerals from the Sahara to the Amazon basin . Saharan dust
1017-418: A distinctive crescent shape with the tips of the crescent directed downwind. The dunes are widely separated by areas of bedrock or reg. Barchans migrate up to 30 meters (98 ft) per year, with the taller dunes migrating faster. Barchans first form when some minor topographic feature creates a sand patch. This grows into a sand mound, and the converging streamlines of the air flow around the mound build it into
1130-459: A further 1,196 species currently recognised but unpublished. They occur within 1,543 genera from 211 families ; there are also 1,276 naturalised alien or invasive plant species, more commonly known as weeds. In the southwest region are some of the largest numbers of plant species for its area in the world. Western Australia's ecoregions include the sandstone gorges of the Kimberley on
1243-403: A lack of storage and refrigeration facilities favour live animals over imports of processed meat. About half of Australia's live cattle exports come from Western Australia. Resource sector growth in recent years has resulted in significant labour and skills shortages, leading to recent efforts by the state government to encourage interstate and overseas immigration. According to the 2006 census,
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#17327651090931356-498: A large aklé or barchanoid dune. They form over a prolonged period of time in areas of abundant sand and show a complex internal structure. Careful 3-D mapping is required to determine the morphology of a draa preserved in the geologic record. Linear dunes can be traced up to tens of kilometers, with heights sometimes in excess of 70 meters (230 ft). They are typically several hundred meters across and are spaced 1 to 2 kilometers (0.62 to 1.24 mi)apart. They sometimes coalesce at
1469-548: A large number of endemic plant species, especially shrubs and wildflowers, including yellow flame and toothbrush grevilleas , fan-flowers , and cockies' tongues . The heath is scattered with woodland of Banksia and other trees including the red-blossomed quandong (desert peach) and firewood banksia . Going further inland, especially in river valleys where the soil is better, eucalyptus woodlands including tuart ( Eucalyptus gomphocephala ) occur. The wetlands meanwhile have been particularly important ecologically, supporting
1582-476: A natural interconnected drainage system which found its way into the Swan River at East Perth through Claise Brook. In 1833, water draining from Lakes Kingsford, Irwin, Sutherland, and Henderson was used to drive a water-driven mill located in Mill Street. Maps: Australia's bioregions IBRA 5.1 IBRA 6.1 Explorer Western Australia Western Australia (WA) is the westernmost state of Australia . It
1695-411: A network of sinuous ridges perpendicular to the wind direction. Aklé dunes are preserved in the geologic record as sandstone with large sets of cross-bedding and many reactivation surfaces. Draas are very large composite transverse dunes. They can be up to 4,000 meters (13,000 ft) across and 400 meters (1,300 ft) high and extend lengthwise for hundreds of kilometers. In form, they resemble
1808-517: A result, the South West region of the state has a higher concentration of rare, threatened or endangered flora and fauna than many areas of Australia, making it one of the world's biodiversity "hot spots". Large areas of the state's wheatbelt region have problems with dryland salinity and the loss of fresh water. The southwest coastal area has a Mediterranean climate . It was originally heavily forested, including large stands of karri , one of
1921-507: A rich habitat of many plant varieties. The Swan Coastal Plain is a particularly important centre for certain types of plants, including Banksia , but also Caladenia orchids and Leucopogon shrubs, indeed some genera, such as the Dryandra series of Banksia and the Synaphea flowers are found nowhere else in the world. Other flora of the plain includes a type of mistletoe called
2034-553: A scientific paper, General view of the botany of the vicinity of Swan River . It discusses the vegetation of the Swan River Colony . Europeans began to settle permanently in 1826 when Albany was claimed by Britain to forestall French claims to the western third of the continent. Perth was founded as the Swan River Colony in 1829 by British and Irish settlers, though the outpost languished. Its officials eventually requested convict labour to augment its population. By
2147-405: A sheet-like surface of rock fragments that remains after wind and water have removed the fine particles. The rock mantle in desert pavements protects the underlying material from further deflation. Areas of desert pavement form the regs or stony deserts of the Sahara . These are further divided into rocky areas called hamadas and areas of small rocks and gravel called serirs . Desert pavement
2260-628: A significant fishing industry. Products for local consumption and export include western rock lobsters , prawns, crabs, shark and tuna, as well as pearl fishing in the Kimberley region of the state. Processing is conducted along the west coast. Whaling was a key marine industry but ceased at Albany in 1978. Western Australia has the world's biggest plantations of both Indian sandalwood (northern WA) and Australian sandalwood (semi-arid regions), which are used to produce sandalwood oil and incense . The WA sandalwood industry provides about 40% of
2373-403: A vigorous low-latitude wind system plus more exposed continental shelf due to low sea levels. Wind-deposited sand bodies occur as ripples and other small-scale features, sand sheets , and dunes . Wind blowing on a sand surface ripples the surface into crests and troughs whose long axes are perpendicular to the wind direction. The average length of jumps during saltation corresponds to
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#17327651090932486-490: Is 1,862 km (1,157 mi). There are 20,781 km (12,913 mi) of coastline, including 7,892 km (4,904 mi) of island coastline. The total land area occupied by the state is 2.5 million km (970 thousand sq mi). The bulk of Western Australia consists of the extremely old Yilgarn craton and Pilbara craton which merged with the Deccan Plateau of India, Madagascar and
2599-450: Is a major world producer of bauxite, which is processed into alumina at four refineries providing 11% of total world production. Until 2020 diamonds were extracted from the world's largest diamond mine in the far north Kimberley region. Coal mined at Collie is the main fuel for baseload electricity generation in the state's south-west. Agricultural production in WA is a major contributor to
2712-535: Is a process of larger grains sliding or rolling across the surface. Saltation refers to particles bouncing across the surface for short distances. Suspended particles are fully entrained in the wind, which carries them for long distances. Saltation likely accounts for 50–70 % of deflation, while suspension accounts for 30–40 % and surface creep accounts for 5–25 %. Regions which experience intense and sustained erosion are called deflation zones. Most aeolian deflation zones are composed of desert pavement ,
2825-576: Is also important in periglacial areas, on river flood plains , and in coastal areas. Coastal winds transport significant amounts of siliciclastic and carbonate sediments inland, while wind storms and dust storms can carry clay and silt particles great distances. Wind transports much of the sediments deposited in deep ocean basins. In ergs (desert sand seas), wind is very effective at transporting grains of sand size and smaller. Particles are transported by winds through suspension, saltation (skipping or bouncing) and creeping (rolling or sliding) along
2938-479: Is also responsible for forming red clay soils in southern Europe. Dust storms are wind storms that have entrained enough dust to reduce visibility to less than 1 kilometer (0.6 mi). Most occur on the synoptic (regional) scale, due to strong winds along weather fronts , or locally from downbursts from thunderstorms. Crops , people, and possibly even climates are affected by dust storms. On Earth, dust can cross entire oceans, as occurs with dust from
3051-469: Is attributed by historians as an important factor driving the state's population and economic growth. Following a campaign led by Forrest, electors of the colony of Western Australia voted in favour of federation with the five other Australian colonies, resulting in Western Australia officially becoming a state on 1 January 1901. Western Australia is bounded to the east by longitude 129°E,
3164-786: Is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Australia is Australia’s largest state, with a land area of 2,527,013 square kilometres (975,685 sq mi), and is also the second-largest subdivision of any country on Earth, surpassed only by the Sakha Republic in eastern Russia, and formerly Northwest Territories in Canada, before
3277-573: Is currently tilted 10 degrees away from the South Pole towards Western Australia, allowing for aurora australis displays as far north as Geraldton . Western Australia is home to around 630 species of birds (depending on the taxonomy used). Of these around 15 are endemic to the state. The best areas for birds are the southwestern corner of the state and the area around Broome and the Kimberley. The Flora of Western Australia comprises 10,162 published native vascular plant species, along with
3390-503: Is derived from the name of the Greek god Aeolus , the keeper of the winds. Aeolian processes are those processes of erosion , transport , and deposition of sediments that are caused by wind at or near the surface of the earth. Sediment deposits produced by the action of wind and the sedimentary structures characteristic of these deposits are also described as aeolian . Aeolian processes are most important in areas where there
3503-457: Is doing at every stage of the year, as well as understanding respect for the land in relation to plant and animal fertility cycles and land and animal preservation. The south west region of Western Australia was one of the first places on earth to experience the effects of human induced climate change, namely a significant decline in annual rainfall. The drying climate is expected to continue and exacerbate bushfires. The summer of 2021/22 has been
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3616-440: Is downwind movement of particles in a series of jumps or skips. Saltation is most important for grains of up to 2 mm in size. A saltating grain may hit other grains that jump up to continue the saltation. The grain may also hit larger grains (over 2 mm in size) that are too heavy to hop, but that slowly creep forward as they are pushed by saltating grains. Surface creep accounts for as much as 25 percent of grain movement in
3729-538: Is endemic to sand dunes in the area, and is threatened by residential development. Much of the plain has been cleared for agriculture and urban development, especially in and around Perth, where the heath has been almost entirely cleared as far as the Darling Scarp and the city is spreading up and down the coast. Although some areas are protected, clearance is going on while the plant disease Phytophthora dieback and changes to traditional fire regimens affect
3842-552: Is extremely common in desert environments. Blowouts are hollows formed by wind deflation. Blowouts are generally small, but may be up to several kilometers in diameter. The smallest are mere dimples 0.3 meters (1 ft) deep and 3 meters (10 ft) in diameter. The largest include the blowout hollows of Mongolia, which can be 8 kilometers (5 mi) across and 60 to 100 meters (200 to 400 ft) deep. Big Hollow in Wyoming , US, extends 14 by 9.7 kilometers (9 by 6 mi) and
3955-697: Is little or no vegetation. However, aeolian deposits are not restricted to arid climates. They are also seen along shorelines; along stream courses in semiarid climates; in areas of ample sand weathered from weakly cemented sandstone outcrops; and in areas of glacial outwash . Loess , which is silt deposited by wind, is common in humid to subhumid climates. Much of North America and Europe are underlain by sand and loess of Pleistocene age originating from glacial outwash. The lee (downwind) side of river valleys in semiarid regions are often blanketed with sand and sand dunes. Examples in North America include
4068-399: Is more important than erosion by wind, but wind erosion is important in semiarid and arid regions. Wind erosion is increased by some human activities, such as the use of 4x4 vehicles . Deflation is the lifting and removal of loose material from the surface by wind turbulence. It takes place by three mechanisms: traction/surface creep, saltation , and suspension. Traction or surface creep
4181-435: Is most applicable in areas devoid of vegetation. In 1941, John Tilton Hack added parabolic dunes, which are strongly influenced by vegetation, to the list of dune types. The discovery of dunes on Mars reinvigorated aeolian process research, which increasingly makes use of computer simulation. Wind-deposited materials hold clues to past as well as to present wind directions and intensities. These features help us understand
4294-504: Is now known as Cape Inscription, Dirk Hartog Island . For the rest of the 17th century, other Dutch and British navigators encountered the coast of what Abel Tasman named New Holland in 1644, usually unintentionally as demonstrated by the many shipwrecks along the coast of ships that deviated from the Brouwer Route (because of poor navigation and storms). By the late 18th century, British and French sailors had begun to explore
4407-575: Is on the Loess Plateau in China . This very same Asian dust is blown for thousands of miles, forming deep beds in places as far away as Hawaii. The Peoria Loess of North America is up to 40 meters (130 ft) thick in parts of western Iowa . The soils developed on loess are generally highly productive for agriculture. Small whirlwinds, called dust devils , are common in arid lands and are thought to be related to very intense local heating of
4520-609: Is that these dunes result from secondary flow , though the precise mechanism remains uncertain. Complex dunes (star dunes or rhourd dunes) are characterized by having more than two slip faces. They are typically 500 to 1,000 meters (1,600 to 3,300 ft) across and 50 to 300 meters (160 to 980 ft) high. They consist of a central peak with radiating crests and are thought to form where strong winds can come from any direction. Those in Gran Desierto de Altar of Mexico are thought to have formed from precursor linear dunes due to
4633-400: Is the northern tropical regions. The Kimberley has an extremely hot monsoonal climate with average annual rainfall ranging from 500 to 1,500 millimetres (20–60 in), but there is a very long almost rainless season from April to November. Eighty-five percent of the state's runoff occurs in the Kimberley, but because it occurs in violent floods and because of the insurmountable poverty of
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4746-463: Is the wearing down by collisions of particles entrained in a moving fluid. It is effective at rounding sand grains and at giving them a distinctive frosted surface texture. Collisions between windborne particles is a major source of dust in the size range of 2-5 microns. Most of this is produced by the removal of a weathered clay coating from the grains. Wind dominates the transport of sand and finer sediments in arid environments. Wind transport
4859-437: Is up to 90 meters (300 ft) deep. Abrasion (also sometimes called corrasion ) is the process of wind-driven grains knocking or wearing material off of landforms . It was once considered a major contributor to desert erosion, but by the mid-20th Century, it had come to be considered much less important. Wind can normally lift sand only a short distance, with most windborne sand remaining within 50 centimeters (20 in) of
4972-441: Is usually less than the fluid threshold. In other words, there is hysteresis in the wind transport system. Small particles may be held in the atmosphere in suspension. Turbulent air motion supports the weight of suspended particles and allows them to be transported for great distances. Wind is particularly effective at separating sediment grains under 0.05 mm in size from coarser grains as suspended particles. Saltation
5085-768: The Bassendean dunes , which run from west to east (in increasing age) from the coastline to the major faults which form the eastern boundary of the plain. The plain is bounded to the east by the Darling Scarp , to the north by a subsidiary fault running north-west from Bullsbrook , and to the south by the Collie-Naturaliste Scarp . The Pinjarra plain lies between the Bassendean dunes and the eastern scarps. Early work on all three dune systems considered them to have been formed at differing times by
5198-513: The Christmas tree . The coastal plains are home to a number of marsupials from the large western grey kangaroo to the very small southwestern pygmy possum and mouse-like honey possum . Remnant populations of some marsupials are found on offshore islands including the Tammar wallaby and the quokka , the latter particularly on Rottnest Island . The coastal plains skink , discovered in 2012,
5311-641: The Group Settlement Scheme of the 1920s, which encouraged farmers to settle the southwest—increased awareness of Australia's western third as a destination for colonists. Led by immigrants from the British Isles, Western Australia's population developed at a faster rate during the twentieth century than it had previously. After World War II , both the eastern states and Western Australia received large numbers of Italians , Croatians and Macedonians . Despite this, Britain has contributed
5424-588: The Kaapvaal and Zimbabwe cratons of Southern Africa, in the Archean Eon to form Ur , one of the oldest supercontinents on Earth (3 – 3.2 billion years ago). In May 2017, evidence of the earliest known life on land may have been found in 3.48-billion-year-old geyserite and other related mineral deposits (often found around hot springs and geysers ) uncovered in the Pilbara craton. Because
5537-551: The Platte , Arkansas , and Missouri Rivers. Wind erodes the Earth's surface by deflation (the removal of loose, fine-grained particles by the turbulent action of the wind) and by abrasion (the wearing down of surfaces by the grinding action and sandblasting by windborne particles). Once entrained in the wind, collisions between particles further break them down, a process called attrition . Worldwide, erosion by water
5650-496: The Swan River Colony with Perth as its capital in 1829. The Western Australian gold rushes of the late 19th century resulted in a significant population influx. The colony was granted responsible government in 1890, the last of the Australian colonies to become self-governing, and federated with the other colonies in 1901. Western Australia's mining sector is a key driver of the state economy . The late 20th century saw
5763-555: The Wheatbelt and temperate southern coastal regions, pastoralism in marginal grassland areas, forestry in the south-west and fishing (including pearling and, historically, whaling ). Western Australia has a geological history dating back to 4.4 billion years ago when Hadean zircons were formed. The earliest direct known life on land, known as stromatolites , started to be created by microbes at around 3.48 billion years ago. The first human inhabitants of Australia arrived from
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#17327651090935876-462: The climax vegetations old growth forests observed at the time of first contact. At this time, the kwongan heathland was much more widespread along the coast. In the 1830s, it was originally named Great Plain of Quartania or Plain of Quartania by James Stirling, the first governor of Western Australia, but those terms have fallen into disuse. European settlement led to many of the wetlands areas being drained for land reclamation to take advantage of
5989-489: The tallest trees in the world. This agricultural region is one of the nine most bio-diverse terrestrial habitats, with a higher proportion of endemic species than most other equivalent regions. Thanks to the offshore Leeuwin Current , the area is one of the top six regions for marine biodiversity and contains the most southerly coral reefs in the world. Average annual rainfall varies from 300 millimetres (12 in) at
6102-438: The wavelength , or distance between adjacent crests, of the ripples. In ripples, the coarsest materials collect at the crests causing inverse grading . This distinguishes small ripples from dunes, where the coarsest materials are generally in the troughs. This is also a distinguishing feature between water laid ripples and aeolian ripples. A sand shadow is an accumulation of sand on the downwind side of an obstruction, such as
6215-403: The windward side. The downwind portion of the dune, the lee slope, is commonly a steep avalanche slope referred to as a slipface . Dunes may have more than one slipface. The minimum height of a slipface is about 30 centimeters. Wind-blown sand moves up the gentle upwind side of the dune by saltation or creep. Sand accumulates at the brink, the top of the slipface. When the buildup of sand at
6328-576: The 1890s around Kalgoorlie . In 1887, a new constitution was drafted, providing for the right of self-governance of European Australians, and in 1890, the act granting self-government to the colony was passed by the British Parliament . John Forrest became the first Premier of Western Australia . In 1896, after discoveries of gold at Coolgardie and Kalgoorlie , the Western Australian Parliament authorised
6441-433: The 2016 census, 75.2% of inhabitants spoke only English at home, with the next most common languages being Mandarin (1.9%), Italian (1.2%), Vietnamese (0.8%), Cantonese (0.8%) and Tagalog (0.6%). According to the 2021 census, Christianity is the major religious affiliation in WA, followed by 41.1% of its population. In 1971, Christianity was followed by 85.5% of the population and it has been declining since, while
6554-499: The Earth's total land surface. The sandy areas of today's world are somewhat anomalous. Deserts, in both the present day and in the geological record, are usually dominated by alluvial fans rather than dune fields. The present relative abundance of sandy areas may reflect reworking of Tertiary sediments following the Last Glacial Maximum. Most modern deserts have experienced extreme Quaternary climate change, and
6667-592: The Pliocene-Pleistocene during the last ice age . Offshore, the sand dune system and surficial deposits transition into a system of partly eroded limestones and sandy limestones. These form a series of drowned cuestas which today form submerged reefs. Because of the steepness and orientation of the Darling Scarp, watercourses run off the scarp in a westerly direction. On reaching the Swan Coastal Plain, they encounter two obstacles: firstly,
6780-675: The Sahara that reaches the Amazon Basin . Dust storms on Mars periodically engulf the entire planet. When the Mariner 9 spacecraft entered its orbit around Mars in 1971, a dust storm lasting one month covered the entire planet, thus delaying the task of photo-mapping the planet's surface. Most of the dust carried by dust storms is in the form of silt -size particles. Deposits of this windblown silt are known as loess . The thickest known deposit of loess, up to 350 meters (1,150 ft),
6893-587: The Western Australian coast. The Baudin expedition of 1800–03 included the coast of Western Australia and resulted in the Freycinet Map of 1811 , the first published map featuring the full outline of Australia. The name New Holland remained in popular and semi-official use until at least the mid-1850s; that is, it was in use for about 206 years in comparison to the name Australia which to date has been in use for about 195 years. The origins of
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#17327651090937006-442: The air that results in instabilities of the air mass. Dust devils may be as much as one kilometer high. Dust devils on Mars have been observed as high as 10 kilometers (6.2 mi), though this is uncommon. Wind is very effective at separating sand from silt and clay. As a result, there are distinct sandy (erg) and silty (loess) aeolian deposits, with only limited interbedding between the two. Loess deposits are found further from
7119-556: The arms of the dune. Clay dunes are uncommon but have been found in Africa, Australia, and along the Gulf Coast of North America. These form on mud flats on the margins of saline bodies of water subject to strong prevailing winds during a dry season. Clay particles are bound into sand-sized pellets by salts and are then deposited in the dunes, where the return of the cool season allows the pellets to absorb moisture and become bound to
7232-442: The brink exceeds the angle of repose , a small avalanche of grains slides down the slipface. Grain by grain, the dune moves downwind. Dunes take three general forms. Linear dunes, also called longitudinal dunes or seifs, are aligned in the direction of the prevailing winds. Transverse dunes, which include crescent dunes (barchans), are aligned perpendicular to the prevailing winds. More complex dunes, such as star dunes, form where
7345-399: The city. Lake Monger was originally part of a series of freshwater wetlands running north from the Swan River along the coastal plain for about 50 kilometres (31 mi). Lake Monger with Georgiana Lake and Lake Sutherland (both near Mitchell Freeway , near Sutherland and Newcastle streets) and Herdsman Lake made up what was known as "The Great Lakes District". Other lakes and swamps in
7458-805: The coast around the Margaret River wine-growing area. Going east along the Southern Ocean coast is the Goldfields-Esperance region, including the Esperance mallee and the Coolgardie woodlands inland around town of Coolgardie . Deserts occupy the interior, including the Great Sandy-Tanami desert , Gibson Desert , Great Victoria Desert , and Nullarbor Plain . In 1831 Scottish botanist Robert Brown produced
7571-626: The coast of Western Australia. On 7 March 1831 it was transferred to the control of the Swan River Colony, and named Albany in 1832. In 1829 the Swan River Colony was established on the Swan River by Captain James Stirling . By 1832, the British settler population of the colony had reached around 1,500, and the official name of the colony was changed to Western Australia on 6 February that year. The two separate townsites of
7684-592: The coastal plain, Ellen Brook runs south for around 30 kilometres (19 mi), picking up a number of watercourses along the way, before finally emptying into the Swan River. Another example is the Serpentine River , which runs west to less than 10 kilometres (6.2 mi) from the coast, then turns south, running parallel with the coast for nearly 20 kilometres (12 mi) before disgorging into Peel Inlet . The dune topology also results in extensive north-to-south-oriented chains of wetlands, again located in
7797-730: The coastal plains, in some cases forming a sharp escarpment (as with the Darling Range/ Darling Scarp near Perth). The extreme age of the landscape has meant that the soils are remarkably infertile and frequently laterised . Even soils derived from granitic bedrock contain an order of magnitude less available phosphorus and only half as much nitrogen as soils in comparable climates in other continents. Soils derived from extensive sandplains or ironstone are even less fertile, nearly devoid of soluble phosphate and deficient in zinc , copper, molybdenum and sometimes potassium and calcium . The infertility of most of
7910-425: The colony developed slowly into the port city of Fremantle and the state's capital, Perth . York was the first inland settlement in Western Australia, situated 97 kilometres (60 mi) east of Perth and settled on 16 September 1831. York was the staging point for early explorers who discovered the rich gold reserves of Kalgoorlie. Population growth was very slow until significant discoveries of gold were made in
8023-471: The creation of Nunavut. It is also the largest proper subnational entity, being a state rather than a territory or an autonomous region. Western Australia has a diverse range of climates, including tropical conditions in the Kimberley , deserts in the interior (including the Great Sandy Desert , Little Sandy Desert , Gibson Desert , and Great Victoria Desert ) and a Mediterranean climate on
8136-514: The deposition of sands carried by wind ( aeolian and/or by river processes (fluviatile). More recently, later authors have argued that these sandplains are mostly the product of in situ weathering. The carbonate material of all three dune systems has been completely leached, leaving dunes which consist solely of quartz sand. Within the Spearwood dunes, the yellow or grey sand may be several metres thick. The dune systems have been much studied, as
8249-432: The development of the state's significant iron ore mining industry – the world's largest – as well as primarily offshore petroleum and natural gas resources . Gold mining retains a significant presence and many other mineral commodities are mined, with Perth being a major centre for associated services. Outside of mining, primary industry is the other significant contributor to the state's economy, including agriculture in
8362-415: The directions of the winds are highly variable. Additional dune types arise from various kinds of topographic forcing, such as from isolated hills or escarpments. Transverse dunes occur in areas dominated by a single direction of the prevailing wind. In areas where sand is not abundant, transverse dunes take the form of barchans or crescent dunes. These are not common, but they are highly recognizable, with
8475-428: The distinctive crescent shape. Growth is ultimately limited by the carrying capacity of the wind, which as the wind becomes saturated with sediments, builds up the slip face of the dune. Because barchans develop in areas of limited sand availability, they are poorly preserved in the geologic record. Where sand is more abundant, transverse dunes take the form of aklé dunes, such as those of the western Sahara. These form
8588-628: The dune surface. Deserts cover 20 to 25 percent of the modern land surface of the earth, mostly between the latitudes of 10 to 30 degrees north or south. Here the descending part of the tropical atmospheric circulation (the Hadley cell ) produces high atmospheric pressure and suppresses precipitation. Large areas of this desert is floored with windblown sand. Such areas are called ergs when they exceed about 125 square kilometers (48 sq mi) in area or dune fields when smaller. Ergs and dune fields make up about 20% of modern deserts or about 6% of
8701-569: The edge of the Wheatbelt region to 1,400 millimetres (55 in) in the wettest areas near Northcliffe , but from November to March, evaporation exceeds rainfall, and it is generally very dry. Plants are adapted to this as well as the extreme poverty of all soils. The central two-thirds of the state is arid and sparsely inhabited. The only significant economic activity is mining. Annual rainfall averages less than 300 millimetres (8–10 in), most of which occurs in sporadic torrential falls related to cyclone events in summer. An exception to this
8814-399: The fertile soil for farming enterprises, and for expansion of parks and recreation areas. The city of Perth sits on an area of reclaimed wetlands. Between 49% (Riggert, 1966) and 80% (Godfrey, 1989) of the wetlands on the coastal plain is thought to have been drained, filled, or cleared since 1832. Lake Monger and Herdsman Lake are the last two major wetlands remaining in close proximity to
8927-611: The generally shallow soils, the only development has taken place along the Ord River . Snow is rare in the state and typically occurs only in the Stirling Range near Albany , as it is the only mountain range far enough south and sufficiently elevated. More rarely, snow can fall on the nearby Porongurup Range . Snow outside these areas is a major event; it usually occurs in hilly areas of southwestern Australia. The most widespread low-level snow occurred on 26 June 1956 when snow
9040-466: The greatest number of immigrants to this day. Western Australia—particularly Perth—has the highest proportion of British-born of any state: 10.3% in 2011, compared to a national average of 5.1%. This group is heavily concentrated in certain parts, where they account for a quarter of the population. Perth's metropolitan area (including Mandurah ) had an estimated population of 2,043,138 in June 2017 (79% of
9153-404: The ground. The minimum wind velocity to initiate transport is called the fluid threshold or static threshold and is the wind velocity required to begin dislodging grains from the surface. Once transport is initiated, there is a cascade effect from grains tearing loose other grains, so that transport continues until the wind velocity drops below the dynamic threshold or impact threshold , which
9266-554: The heathland vegetation including the Banksia trees. Protected areas include Kings Park , Beeliar Wetlands , Star Swamp , Hepburn Heights Bushland , Canning River Regional Park , Bold Park , Whiteman Park , Kensington Bushland and Thomsons Lake . Traditionally, this area was under the care and control of the Yued, Whadjuk , Binjareb , and Wardandi Noongar peoples, whose hunter-gathering firestick farming practices maintained
9379-474: The high permeability of the soil results in the loss of much water. Much flow is lost, and some watercourses simply cease to flow, for example, Wungong Brook , Cardup Brook , and Manjedal Brook . Secondly, the sequence of north-to-south-oriented dunes create obstacles to further westerly flow. Many watercourses turn at right angles and flow south or north along the dune swales, and in some cases this allows multiple watercourses to coalesce. For example, on reaching
9492-460: The hottest on record, with many consecutive days over 40 degrees Celsius. The Swan Coastal Plain is a specific botanical province. Southwestern Australia is very rich in flora, with an estimated 8,000 species, a quarter of which can be found on this coastal strip. The traditional flora of the dunes and the fairly infertile plain was dense shrubby kwongan heathland adapted to the poor soils, dry summers, and regular fires. Kwongan vegetation contains
9605-630: The immediate northern vicinity of the early Perth township were Lake Kingsford (site of the current Perth railway station ), Lake Irwin ( Perth Entertainment Centre ) and further north were Stone's Lake (Perth Oval), Lake Poullet (First Swamp, part of what is now Birdwood Square), Lake Thomson (Mews Swamp, between Lake, Brisbane, and Beaufort Streets) and Lake Henderson (parts of what is now Robertson Park and Dorrien Gardens). Further north still lay Second Swamp (Bulwer Street, east of Lake Street), Third Swamp (Hyde Park), and Three Island Lake and Smith's Lake (now Charles Veryard Reserve). Many of these lakes formed
9718-555: The international sandalwood oil market. In recent years, tourism has grown in importance, with significant numbers of visitors to the state coming from the UK and Ireland (28%), other European countries (14%) Singapore (16%), Japan (10%) and Malaysia (8%). Revenue from tourism is a strong economic driver in many of the smaller population centres outside of Perth, especially in coastal locations. Aeolian processes Aeolian processes , also spelled eolian , pertain to wind activity in
9831-401: The larger West Australian Shield division. The coastal plain is a 30-kilometre-wide (19 mi) strip on the Indian Ocean coast directly west of the Darling Scarp uplands running from Cape Naturaliste in the south to north of the city of Perth . The plain mainly consists of fairly infertile sandy soil along with coastal sand dunes, river estuaries, and a number of wetlands kept back from
9944-525: The margins of dune fields, although they also occur within ergs. Conditions that favor the formation of sand sheets, instead of dunes, may include surface cementation, a high water table, the effects of vegetation, periodic flooding, or sediments rich in grains too coarse for effective saltation. A dune is an accumulations of sediment blown by the wind into a mound or ridge . They differ from sand shadows or sand drifts in that they are independent of any topographic obstacle. Dunes have gentle upwind slopes on
10057-488: The median individual income was A$ 500 per week in Western Australia (compared to A$ 466 in Australia as a whole). The median family income was A$ 1246 per week (compared to A$ 1171 for Australia). Recent growth has also contributed to significant rises in average property values in 2006, although values plateaued in 2007. Located south of Perth, the heavy industrial area of Kwinana had the nation's largest oil refinery with
10170-426: The meridian 129 degrees east of Greenwich, which defines the border with South Australia and the Northern Territory , and bounded by the Indian Ocean to the west and north. The International Hydrographic Organization (IHO) designates the body of water south of the continent as part of the Indian Ocean; in Australia it is officially gazetted as the Southern Ocean . The total length of the state's eastern border
10283-421: The moulting of swans are all helpful indicators that the seasons are changing. The Nyoongar seasons can be long or short and are indicated by what is happening and changing around us rather than by dates on a calendar. Aligning Nyoongar seasons with Western calendar months can provide an overview of a typical year. This six season calendar is extremely important to Nyoongar people, as it is a guide to what nature
10396-513: The north "over 50,000 years ago and possibly as much as 70,000 years ago". Over thousands of years they eventually spread across the whole landmass. These Indigenous Australians were long established throughout Western Australia by the time European explorers began to arrive in the early 17th century. The first Europeans to visit Western Australia were those of the Dutch Dirk Hartog expedition, who on 25 October 1616 landed at what
10509-538: The northern coast, and below that the drier Victoria Plains tropical savanna inland, and the semi-desert Pilbara shrublands , Carnarvon xeric shrublands , and Western Australian mulga shrublands to the southwest. Southwards along the coast are the Southwest Australia savanna and the Swan Coastal Plain around Perth, with the jarrah-karri forest and shrublands on the southwest corner of
10622-582: The only mountain-building since then has been of the Stirling Range with the rifting from Antarctica , the land is extremely eroded and ancient, with no part of the state above 1,249 metres (4,098 ft) AHD (at Mount Meharry in the Hamersley Range of the Pilbara region). Most of the state is a low plateau with an average elevation of about 400 metres (1,200 ft), very low relief, and no surface runoff . This descends relatively sharply to
10735-610: The original source of sediments than ergs. An example of this is the Sand Hills of Nebraska , US. Here vegetation-stabilized sand dunes are found to the west and loess deposits to the east, further from the original sediment source in the Ogallala Formation at the feet of the Rocky Mountains. Some of the most significant experimental measurements on aeolian landforms were performed by Ralph Alger Bagnold ,
10848-443: The percentage of people who identified as having no religious affiliation has increased from 8.7% in 1971 to 42.9% in 2021. A small minority of the population are Muslims (2.5%), Buddhists (2.2%) and Hindus (2.0%). Western Australia's economy is largely driven by extraction and processing of a diverse range of mineral and petroleum commodities. The structure of the economy is closely linked to these natural resources, providing
10961-460: The present climate and the forces that molded it. For example, vast inactive ergs in much of the modern world attest to late Pleistocene trade wind belts being much expanded during the Last Glacial Maximum. Ice cores show a tenfold increase in non-volcanic dust during glacial maxima. The highest dust peak in the Vostok ice cores dates to 20 to 21 thousand years ago. The abundant dust is attributed to
11074-474: The present state began with the establishment by Lockyer of a convict-supported settlement from New South Wales at King George III Sound . The settlement was formally annexed on 21 January 1827 by Lockyer when he commanded the Union Jack be raised and a feu de joie fired by the troops. The settlement was founded in response to British concerns about the possibility of a French colony being established on
11187-526: The prevailing wind. They form mostly in softer material such as silts. Abrasion produces polishing and pitting, grooving, shaping, and faceting of exposed surfaces. These are widespread in arid environments but geologically insignificant. Polished or faceted surfaces called ventifacts are rare, requiring abundant sand, powerful winds, and a lack of vegetation for their formation. In parts of Antarctica wind-blown snowflakes that are technically sediments have also caused abrasion of exposed rocks. Attrition
11300-550: The raising of a loan to construct a pipeline to transport 23 megalitres (5 million imperial gallons) of water per day to the burgeoning population on the goldfields. The pipeline, known as the Goldfields Water Supply Scheme , was completed in 1903. C. Y. O'Connor , Western Australia's first engineer-in-chief, designed and oversaw the construction of the pipeline. It carries water 530 km (330 mi) from Perth to Kalgoorlie , and
11413-573: The sea by the dunes. A number of rivers cross the plain from east to west from the Darling Scarp towards the sea, including the Swan and its main tributary, the Canning . The sediments of the Perth Basin are Tertiary and Quaternary in age immediately below Perth and include coquina , travertine , and sandy limestones with abundant shelly material. Perth is sited on a set of sand dunes formed during
11526-401: The soils has required heavy application by farmers of fertilisers. These have resulted in damage to invertebrate and bacterial populations. The grazing and use of hoofed mammals and, later, heavy machinery through the years have resulted in compaction of soils and great damage to the fragile soils. Large-scale land clearing for agriculture has damaged habitats for native flora and fauna. As
11639-533: The south-west and southern coastal areas. As of 2021, the state has 2.91 million inhabitants—11 percent of the national total. Over 90 percent of the state's population live in the south-west corner and around 80 percent live in the state capital Perth , leaving the remainder of the state sparsely populated. The Trans-Australian Railway and the Eyre Highway traverse the Nullarbor Plain in
11752-555: The state and national economy. In the period 2010–2019 wheat production in WA has averaged nearly 10 million tonnes (22 billion pounds), valued at $ 2.816 billion in 2019, accounting for half the nation's total and providing $ 2–3 billion in export income. Other significant farm output includes wool, beef, lamb, barley, canola, lupins, oats and pulses. There is a high level of overseas demand for live animals from WA, driven mainly by southeast Asia's feedlots and Middle Eastern countries, where Islamic dietary laws and
11865-431: The state's south-east, providing the principal connection between Western Australia and the population centres in the eastern states . Western Australia's Indigenous peoples have been present for tens of thousands of years. Dutch explorers visited Western Australia from the 17th century, with Dirk Hartog 's 1616 expedition the first Europeans to make landfall. The British claimed Western Australia in 1827 and established
11978-451: The state). Other significant population centres include Bunbury (73,989), Geraldton (37,961), Kalgoorlie-Boulder (30,420), Albany (33,998), Karratha (16,446), Broome (14,501) and Port Hedland (14,285). At the 2016 census, the most commonly nominated ancestries were: 3.1% of the population, or 75,978 people, identified as Indigenous Australians ( Aboriginal Australians and Torres Strait Islanders ) in 2016. At
12091-521: The study of geology and weather and specifically to the wind's ability to shape the surface of the Earth (or other planets ). Winds may erode , transport, and deposit materials and are effective agents in regions with sparse vegetation , a lack of soil moisture and a large supply of unconsolidated sediments . Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts . The term
12204-613: The surface and practically none normally being carried above 2 meters (6 ft). Many desert features once attributed to wind abrasion, including wind caves, mushroom rocks , and the honeycomb weathering called tafoni , are now attributed to differential weathering, rainwash, deflation rather than abrasion, or other processes. Yardangs are one kind of desert feature that is widely attributed to wind abrasion. These are rock ridges, up to tens of meters high and kilometers long, that have been streamlined by desert winds. Yardangs characteristically show elongated furrows or grooves aligned with
12317-585: The swales. For example, the chain of lakes north of Perth includes lakes of the Wanneroo wetlands including – Lake Pinjar , Jandabup Lake and Gnangara Lake . The large bodies of water in the estuary of the Swan River, Perth Water and Melville Water are also located in dune swales. The Swan coastal plain is characterised by a series of sand dune systems, the Quindalup dunes , the Spearwood dunes , and
12430-550: The time transportation ceased in 1868, convicts outnumbered free settlers 9,700 to 7,300. In the 1890s, interstate immigration, resulting from a mining boom in the Goldfields region , resulted in a sharp population increase. Western Australia did not receive significant flows of immigrants from Britain, Ireland or elsewhere in the British Empire until the early 20th century. At that time, its local projects—such as
12543-484: The water retained within them supplies much of Perth's water needs. (See Gnangara Mound ). In the southwest of Australia, the Nyoongar seasonal calendar includes six different seasons in a yearly cycle. These are Birak, Bunuru, Djeran, Makuru, Djilba and Kambarang. Each of the six seasons represents and explains the seasonal changes we see annually. The flowering of many different plants, the hibernation of reptiles and
12656-555: The wind. Sand sheets are flat or gently undulating sandy deposits with only small surface ripples. An example is the Selima Sand Sheet in the eastern Sahara Desert, which occupies 60,000 square kilometers (23,000 sq mi) in southern Egypt and northern Sudan . This consists of a few feet of sand resting on bedrock. Sand sheets are often remarkably flat and are sometimes described as desert peneplains . Sand sheets are common in desert environments, particularly on
12769-653: Was reported in the Perth Hills , as far north as Wongan Hills and as far east as Salmon Gums . However, even in the Stirling Range, snowfalls rarely exceed 5 cm (2 in) and rarely settle for more than one day. The highest observed temperature of 50.7 °C (123.3 °F) was recorded in Onslow on 13 January 2022. The lowest temperature recorded was −7.2 °C (19.0 °F) at Eyre Bird Observatory on 17 August 2008. The south geomagnetic pole
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