A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses and to serve as a navigational aid for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs and safe entries to harbors. Once used, the number of operational lighthouses has declined due to the expense of maintenance and use of electronic navigational systems. Before the development of defined ports, mariners were guided by fires built on hilltops. Since raising the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and promontories, unlike many modern lighthouses; the most famous lighthouse structure from antiquity was the Pharos of Alexandria, which collapsed following a series of earthquakes between 956 and 1323. The intact Tower of Hercules at A Coruña, Spain gives insight into ancient lighthouse construction.
Coins from Alexandria and Laodicea in Syria exist. The modern era of lighthouses began at the turn of the 18th century, as lighthouse construction boomed in lockstep with burgeoning levels of transatlantic commerce. Advances in structural engineering and new and efficient lighting equipment allowed for the creation of larger and more powerful lighthouses, including ones exposed to the sea; the function of lighthouses shifted toward the provision of a visible warning against shipping hazards, such as rocks or reefs. The Eddystone Rocks were a major shipwreck hazard for mariners sailing through the English Channel; the first lighthouse built there was an octagonal wooden structure, anchored by 12 iron stanchions secured in the rock, was built by Henry Winstanley from 1696 to 1698. His lighthouse was the first tower in the world to have been exposed to the open sea; the civil engineer, John Smeaton, rebuilt the lighthouse from 1756–59. He modelled the shape of his lighthouse on that of an oak tree.
He rediscovered and used "hydraulic lime," a form of concrete that will set under water used by the Romans, developed a technique of securing the granite blocks together using dovetail joints and marble dowels. The dovetailing feature served to improve the structural stability, although Smeaton had to taper the thickness of the tower towards the top, for which he curved the tower inwards on a gentle gradient; this profile had the added advantage of allowing some of the energy of the waves to dissipate on impact with the walls. His lighthouse influenced all subsequent engineers. One such influence was Robert Stevenson, himself a seminal figure in the development of lighthouse design and construction, his greatest achievement was the construction of the Bell Rock Lighthouse in 1810, one of the most impressive feats of engineering of the age. This structure was based upon Smeaton's design, but with several improved features, such as the incorporation of rotating lights, alternating between red and white.
Stevenson worked for the Northern Lighthouse Board for nearly fifty years during which time he designed and oversaw the construction and improvement of numerous lighthouses. He innovated in the choice of light sources, reflector design, the use of Fresnel lenses, in rotation and shuttering systems providing lighthouses with individual signatures allowing them to be identified by seafarers, he invented the movable jib and the balance crane as a necessary part for lighthouse construction. Alexander Mitchell designed the first screw-pile lighthouse – his lighthouse was built on piles that were screwed into the sandy or muddy seabed. Construction of his design began in 1838 at the mouth of the Thames and was known as the Maplin Sands lighthouse, first lit in 1841. Although its construction began the Wyre Light in Fleetwood, was the first to be lit; the source of illumination had been wood pyres or burning coal. The Argand lamp, invented in 1782 by the Swiss scientist, Aimé Argand, revolutionized lighthouse illumination with its steady smokeless flame.
Early models used ground glass, sometimes tinted around the wick. Models used a mantle of thorium dioxide suspended over the flame, creating a bright, steady light; the Argand lamp used whale oil, olive oil or other vegetable oil as fuel, supplied by a gravity feed from a reservoir mounted above the burner. The lamp was first produced by Matthew Boulton, in partnership with Argand, in 1784 and became the standard for lighthouses for over a century. South Foreland Lighthouse was the first tower to use an electric light in 1875; the lighthouse's carbon arc lamps were powered by a steam-driven magneto. John Richardson Wigham was the first to develop a system for gas illumination of lighthouses, his improved gas'crocus' burner at the Baily Lighthouse near Dublin was 13 times more powerful than the most brilliant light known. The vaporized oil burner was invented in 1901 by Arthur Kitson, improved by David Hood at Trinity House; the fuel was vaporized at high pressure and burned to heat the mantle, giving an output of over six times the luminosity of traditional oil lights.
The use of gas as illuminant became available with the invention of the Dalén light by Swedish engineer, Gustaf Dalén. He used Agamassan, a substrate, to absorb the gas allowing safe storage and hence
Port Douglas is a town and a locality in the Shire of Douglas, Australia 70 km north of Cairns. In the 2016 census, Port Douglas had a population of 3,504 people; the town's population can double, with the influx of tourists during the peak tourism season from May to September. The town is named in honour of a former Premier of John Douglas. Port Douglas developed based on the mining industry. Other parts of the area were established with timber cutting occurring in the area surrounding the Daintree River and with settlement starting to occur on lots around the Mossman River by 1880. Previous names for the town included Island Point, Port Owen and Salisbury; the town is situated adjacent to two World Heritage areas, the Great Barrier Reef and the Daintree Rainforest. Port Douglas was No. 3 on Australian Traveller magazine's list of 100 Best Towns In Australia. The town is within the federal electorate of Leichhardt, within the state electorate of Cook. At the local level, it is in the local government area of Shire of Douglas.
The Port Douglas township was established in 1877 after the discovery of gold at Hodgkinson River by James Venture Mulligan. Port Douglas Post Office opened on 1 September 1877, it grew and at its peak Port Douglas had a population of 12,000 and 27 hotels. With the construction of the Mulligan Highway it serviced towns as far away as Herberton. Port Douglas State School opened on 11 November 1879, but closed in 1962, it was reopened on 23 January 1989. When the Kuranda Railway from Cairns to Kuranda was completed in 1891, the importance of Port Douglas dwindled along with its population. A cyclone in 1911 which demolished all but two buildings in the town had a significant impact. At its nadir in 1960 the town, by little more than a fishing village, had a population of 100; the Port Douglas War Memorial was unveiled on 10 February 1923 by Mrs Tresize. In the late-1980s, tourism boomed in the region after investor Christopher Skase financed the construction of the Sheraton Mirage Port Douglas Resort.
Its permanent population was 3,205 at the time of the 2011 census. Port Douglas has a number of heritage-listed sites, including: Macrossan Street: FDA Carstens Memorial Wharf Street: St Mary's by the Sea 6 Dixie Street: Port Douglas Wharf 25 Wharf Street: Port Douglas Court House Museum In the 2016 Census, there were 3,504 people in Port Douglas. 56.6% of people were born in Australia. The next most common countries of birth were England 6.3% and New Zealand 5.9%. 76.6% of people spoke only English at home. The most common responses for religion were No Religion, so described 41.1% and Catholic 17.4%. On 5 July 1943, a RAAF Vultee Vengeance crash landed on the beach near Port Douglas. In November 1996 United States President Bill Clinton and First Lady Hillary Clinton chose the town as their only holiday stop on their historic visit to Australia; when dining at a local restaurant they witnessed a couple's wedding certificate. On a return visit on 11 September 2001, Clinton was again dining at a local restaurant, when he was advised of the September 11 attacks.
He returned to the United States the following day. On 4 September 2006, television personality and conservationist Steve Irwin died at Batt Reef, off Port Douglas, after a stingray barb pierced his heart during filming of a documentary called The Ocean's Deadliest. Irwin was filmed snorkelling directly above the stingray when it lashed him with its tail, killing him immediately; the event was reported in Australia and overseas. The annual Port Douglas Carnivale is held in May and runs for 10 days over two weekends, beginning with a parade attracting over 10,000 people. In October Porttoberfest is held; the Great Barrier Reef Marathon Festival is held during October. Port Douglas was a popular location to view the 14 November 2012 solar eclipse that occurred at 6:38 am. Thousands travelled to Port Douglas to see the phenomenon; the music video for Kylie Minogue's 1988 single "It's No Secret" was filmed in Port Douglas. Port Douglas has a tropical monsoon climate according to Köppen climate classification, with hot summers and warm winters, with heavy rainfall occurring from January–March, the wettest month of the year being February.
The average temperature of the sea ranges from 23.7 °C in July to 29.5 °C in January. Kitesurfing is popular at the southern end of Four Mile Beach during the winter months when trade winds blow from the South. Port Douglas is near the Great Barrier Reef. Numerous companies run daily trips from the marina to the outer reef and the Low Isles for scuba diving and snorkelling. Port Douglas is well known for its many restaurants, golf courses, five star resorts; the Port Douglas Community Hall houses the Port Douglas Library, 11-29 Mowbray Street, operated by the Douglas Shire Council. The Library opened in 2010. Another branch library is located in Mossman; the Port Douglas branch of the Queensland Country Women's Association meets at the CWA Hall at 8 Blake Street. Port Douglas State School is a government primary school for girls at Endeavour Street. In 2017, the school had an enrolment of 281 students with 12 non-teaching staff. For secondary school, Port Douglas is within the catchment of Mossman State High School.
Port Douglas Tourism Information Port Douglas News Port Douglas Visitors Guide Port Douglas Webcam Tourism Port Douglas & Daintree University of Queensland: Queensland Places:Port Douglas
The unofficial geographic term Northern Australia includes those parts of Queensland and Western Australia north of latitude 26° and all of the Northern Territory. Those local government areas of Western Australia and Queensland that lie in the north are included. Although it comprises about half of the total area of Australia, Northern Australia includes only about one quarter of the Australian population. However, it includes several sources of Australian exports, being coal from the Great Dividing Range in Queensland/New South Wales and the natural gas and iron ore of the Pilbara region in WA, it includes major natural tourist attractions, such as Uluru, the Great Barrier Reef and the Kakadu National Park. All of Northern Australia is a huge ancient craton that has not experienced geological upheaval since the end of the Precambrian; the only exception to this generalisation is the Wet Tropics of northern Queensland, where active volcanoes have been present as as the Pleistocene. The vast craton in the north and west contains a number of quite rugged mountain ranges, of which the highest are the MacDonnell and Musgrave Ranges on the southern border of the Northern Territory.
These rise to over 1,500 metres, but the most spectacular features are the deep gorges of rivers such as the Finke. Most of the craton, however, is distinctly flat and low-lying with an average elevation of around 400 metres, whilst in the Lake Eyre Basin most of the land is not far above sea level; the climate of the north of Australia ranges from arid in the south to monsoonal in the Top End and Kimberley. On the eastern coast, the climate is much more humid and ranges from humid sub-tropical to humid tropical in the Wet Tropics. Except in the western part of the Pilbara and Gascoyne where the heaviest rain occurs from May to July under northwest cloudbands, rainfall is concentrated in the "summer" months from November to March. For instance, in Burketown, the months May to September are rainless in over fifty percent of years, with over eighty percent of Augusts having no rain. Temperatures in summer are unpleasantly hot apart from the eastern coastal belt. Maximum temperatures elsewhere between October and April range from 30 °C in the south in April to around 40 °C in the inland Pilbara and Kimberley before the wet season breaks.
Further north, maxima are around 32 °C but extreme humidity makes conditions unpleasant. On the coast, maxima in January range from 29 °C in the south to 32 °C, with minima around 21 °C. In July, temperatures show a wider range, from 31 °C in the north to around 19 °C in the south, where minima can be as low as 5 °C in Alice Springs in June and July; the above generalisations, mask the immense variability of the climate throughout the whole region. With the exception of the extreme north of the Northern Territory, rainfall variability throughout Northern Australia is quite markedly higher than most comparable climates in other continents. For example, at Charters Towers, the rainfall over the wet season can vary from less than 100 millimetres in 1901/1902 to over 2,000 millimetres in 1973/1974; the chief cause of this high variability is erratic tropical cyclones, which occur from December to April and in many places can deliver as much as 350 millimetres of rain over a day or two, causing large floods in the region's rivers.
For example, in April 1898, a tropical cyclone gave 740 millimetres in one day at Whim Creek in the Pilbara, but for the whole of 1924 that same station recorded only 4 millimetres for the whole year. Tropical cyclones may cross the coast anywhere in Northern Australia but are most frequent between Derby and Onslow on the west side and between Cooktown and Rockhampton on the east. Inland, variability of rainfall is related to the penetration of the summer monsoon, with high rainfall in seasons like 1973/1974, 1975/1976 and from 1998 to 2001 when the monsoon is most powerful. Climate change has seen increases of up to fifty percent in annual rainfall since 1967 over the western half of Australia's tropics, but has not seen any increase over the east; the increase over the west is sometimes attributed to aerosol pollution over industrialising areas of China and India, but may be related to global warming. Frosts are common in the southern inland during the winter, but in some years, such as 1998, they are much less frequent due to the recent incidence of warm pools in the Indian Ocean.
Except in the Lake Eyre Basin and adjacent areas to the east, the soils of Northern Australia are quite remarkable in global terms for their low fertility and difficulty of working. Most of them consist chiefly of hard laterite developed during period of climate much more humid than that of Darwin today. Since there has been no mountain building in the region since the Precambrian and no glaciation since the Carboniferous, the region's soils have been under continuous weathering without renewal for over 250 million years, as against less than ten thousand for most soils in Europe, North America and New Zealand which have been formed from recent mountain building or glacial scouring of the land; this immensely long weathering time means that nutrient levels in Northern Australian soils are exceptionally low because all soluble minerals have long been weathered out. The major constituents of most soils in Northern Australia are iron and aluminium oxides, both of which are not only insoluble but serve to reduce the soil pH and remove phosphorus from the soil as insoluble iron a
Australia the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the world's sixth-largest country by total area; the neighbouring countries are Papua New Guinea and East Timor to the north. The population of 25 million is urbanised and concentrated on the eastern seaboard. Australia's capital is Canberra, its largest city is Sydney; the country's other major metropolitan areas are Melbourne, Brisbane and Adelaide. Australia was inhabited by indigenous Australians for about 60,000 years before the first British settlement in the late 18th century, it is documented. After the European exploration of the continent by Dutch explorers in 1606, who named it New Holland, Australia's eastern half was claimed by Great Britain in 1770 and settled through penal transportation to the colony of New South Wales from 26 January 1788, a date which became Australia's national day; the population grew in subsequent decades, by the 1850s most of the continent had been explored and an additional five self-governing crown colonies established.
On 1 January 1901, the six colonies federated. Australia has since maintained a stable liberal democratic political system that functions as a federal parliamentary constitutional monarchy, comprising six states and ten territories. Being the oldest and driest inhabited continent, with the least fertile soils, Australia has a landmass of 7,617,930 square kilometres. A megadiverse country, its size gives it a wide variety of landscapes, with deserts in the centre, tropical rainforests in the north-east and mountain ranges in the south-east. A gold rush began in Australia in the early 1850s, its population density, 2.8 inhabitants per square kilometre, remains among the lowest in the world. Australia generates its income from various sources including mining-related exports, telecommunications and manufacturing. Indigenous Australian rock art is the oldest and richest in the world, dating as far back as 60,000 years and spread across hundreds of thousands of sites. Australia is a developed country, with the world's 14th-largest economy.
It has a high-income economy, with the world's tenth-highest per capita income. It is a regional power, has the world's 13th-highest military expenditure. Australia has the world's ninth-largest immigrant population, with immigrants accounting for 26% of the population. Having the third-highest human development index and the eighth-highest ranked democracy globally, the country ranks in quality of life, education, economic freedom, civil liberties and political rights, with all its major cities faring well in global comparative livability surveys. Australia is a member of the United Nations, G20, Commonwealth of Nations, ANZUS, Organisation for Economic Co-operation and Development, World Trade Organization, Asia-Pacific Economic Cooperation, Pacific Islands Forum and the ASEAN Plus Six mechanism; the name Australia is derived from the Latin Terra Australis, a name used for a hypothetical continent in the Southern Hemisphere since ancient times. When Europeans first began visiting and mapping Australia in the 17th century, the name Terra Australis was applied to the new territories.
Until the early 19th century, Australia was best known as "New Holland", a name first applied by the Dutch explorer Abel Tasman in 1644 and subsequently anglicised. Terra Australis still saw occasional usage, such as in scientific texts; the name Australia was popularised by the explorer Matthew Flinders, who said it was "more agreeable to the ear, an assimilation to the names of the other great portions of the earth". The first time that Australia appears to have been used was in April 1817, when Governor Lachlan Macquarie acknowledged the receipt of Flinders' charts of Australia from Lord Bathurst. In December 1817, Macquarie recommended to the Colonial Office. In 1824, the Admiralty agreed that the continent should be known by that name; the first official published use of the new name came with the publication in 1830 of The Australia Directory by the Hydrographic Office. Colloquial names for Australia include "Oz" and "the Land Down Under". Other epithets include "the Great Southern Land", "the Lucky Country", "the Sunburnt Country", "the Wide Brown Land".
The latter two both derive from Dorothea Mackellar's 1908 poem "My Country". Human habitation of the Australian continent is estimated to have begun around 65,000 to 70,000 years ago, with the migration of people by land bridges and short sea-crossings from what is now Southeast Asia; these first inhabitants were the ancestors of modern Indigenous Australians. Aboriginal Australian culture is one of the oldest continual civilisations on earth. At the time of first European contact, most Indigenous Australians were hunter-gatherers with complex economies and societies. Recent archaeological finds suggest. Indigenous Australians have an oral culture with spiritual values based on reverence for the land and a belief in the Dreamtime; the Torres Strait Islanders, ethnically Melanesian, obtained their livelihood from seasonal horticulture and the resources of their reefs and seas. The northern coasts and waters of Australia were visited s
Low Isles Light
Low Isles Light known as Low Islets Light or Low Island Light, is an active lighthouse located on Low Island, a coral cay which together with Woody Island forms the Low Isles group, about 13 kilometres northeast of Port Douglas, Australia. The island is situated on the western edge of the main shipping channel into the harbour of Port Douglas, it marks the entrance to the channel. Built in 1878, it was the first lighthouse in Far North Queensland and more the first to light the Inner Passage of the Great Barrier Reef, its construction is typical to Queensland lighthouses of the time, timber frame clad with galvanized iron, it is the fourth lighthouse of this type constructed in Queensland, though it is the first of them to use portholes. The lighthouse was recommended in February 1876 but construction of the lighthouse and cottages, by W. P. Clark, started more than a year later; the structures were ready and the light was lit in late 1878. The original oil wick light was upgraded to kerosene in 1923, to electricity in 1963 and converted to solar power in 1993, when the station was demanned.
The size of the island mandated a rather compact circular pattern of structures. Other than the lighthouse, none of the original structures survived, the keeper residences being rebuilt in the 1960s. One of the residences now serves as a research station; the station is managed by the Queensland Parks and Wildlife Service. The site can be visited but the tower is closed; the need for lights in the Inner Passage inside the Great Barrier Reef arose with the development of ports in the north of Queensland such as Mackay in 1860 and Bowen in 1864. Access to these ports from the north necessitates the negotiation of the Inner Passage, unlit; the need was noted by a Legislative Council committee in 1864 noting shipping from India and other countries to the north which would avoid the northern ports due to the dangerous navigation required, but no official recommendation was made. A station on Low Island was established 1874. A recommendation for the construction of a permanent lighthouse was made in February 1876 by Commander George Poynter Heath, the first Portmaster of Queensland and the Chairman of the Queensland Marine Board, Commander George Heath, in a letter to the Colonial Treasurer.
While the recommendation was accepted for immediate action, the preparation of plans for the lighthouse was delayed from an unknown reason and tenders were called in March 1877. The contract, for £3,195, was awarded in May 1877 to W. P. Clark, who constructed Queensland's first lighthouse since the separation, Bustard Head Light, in 1868, and, to be awarded the contracts for Cape Cleveland Light and Dent Island Light, Double Island Point Light and Pine Islet Light. Clark committed to completing the lighthouse and cottages in seven months, starting in June 1877. Constructed commenced in Brisbane in July 1877 and by December 1877 the lighthouse was being moved to Low Island. Construction completed by August of that year and light was displayed on 17 September 1878; the lens was a Chance Brothers 3rd order revolving dioptric supported by a roller bearing pedestal and the characteristic mentioned was "attains its greatest brilliancy every minute", with visibility of 14 nautical miles. The tower was painted white.
The original light source was oil wick burners with an intensity of 13,000 cd. Construction included three lighthouse keeper cottages, which were prefabricated elsewhere and brought to the site. In March 1911 the island was hit by a cyclone, stripping it of soil and vegetation, damaging the station buildings; as preparation for transferring the light from the Queensland Government to the Commonwealth Lighthouse Service, an evaluation was made by Commander Brewis in 1912, which recommended an upgrade of the light to incandescent mantle and a change of the characteristic to one flash every ten seconds, as well as the installation of a fog signal. The station was transferred to the Commonwealth in 1915, it was only in 1923 that the recommendation was acted upon, the light source was upgraded to vapourised kerosene with an intensity of 100,000 cd. At the same time, the characteristic was altered, again in 1930. In 1960 two of the three residences were replaced with modern structures. Upgrade to electric operation occurred in 1963 and in the same year three structures were constructed.
The original boathouse, constructed in 1920, was replaced with a new structure, relieving quarters were built and a fuel store was constructed. In 1972 a power house and a bulk fuel store were constructed. In 1992 the Australian Maritime Safety Authority announced its plans to automate the station, remove the light keepers, transfer the island to the responsibility of the Queensland Parks and Wildlife Service; this prompted the foundation of the Low Isles Preservation Society, a community organization with the purpose of protecting the island and the lighthouse. The light was converted to solar power on March 1993, as planned the station was demanned and the site was transferred to the QPWS; the lens, removed at the time is now on display in the Court House Museum of Port Douglas. The last keeper left the island in 1994; the current light characteristic is a white flash every ten seconds visible for a distance of 17 nautical miles. The apparatus is a VRB-25 rotating at 1 rpm; the light source is a 12 Volt 20 Watt Halogen lamp with an intensity of 49,212 cd.
The tower stands on a concrete base. It is conical in shape, built of an internal timber frame, clad with galvanized iron plates riveted together, painted white. Sunlight is provided through
A reef is a bar of rock, coral or similar material, lying beneath the surface of water. Many reefs result from natural, abiotic processes—deposition of sand, wave erosion planing down rock outcrops, etc.—but the best known reefs are the coral reefs of tropical waters developed through biotic processes dominated by corals and coralline algae. Artificial reefs sometimes have a role in enhancing the physical complexity of featureless sand bottoms, in order to attract a diverse assemblage of organisms algae and fish. Earth's largest reef system is the Great Barrier Reef in Australia, at a length of over 2,300 kilometres. There is a variety of biotic reef types, including oyster reefs and sponge reefs, but the most massive and distributed are tropical coral reefs. Although corals are major contributors to the framework and bulk material comprising a coral reef; these biotic reef types take on additional names depending upon how the reef lies in relation to the land, if any. Reef types include fringing reefs, barrier reefs, atolls.
A fringing reef is a reef, attached to an island. A barrier reef forms a calcareous barrier around an island resulting in a lagoon between the shore and the reef. An atoll is a ring reef with no land present; the reef front is a high energy locale whereas the internal lagoon will be at a lower energy with fine grained sediments. Ancient reefs buried within stratigraphic sections are of considerable interest to geologists because they provide paleo-environmental information about the location in Earth's history. In addition, reef structures within a sequence of sedimentary rocks provide a discontinuity which may serve as a trap or conduit for fossil fuels or mineralizing fluids to form petroleum or ore deposits. Corals, including some major extinct groups Rugosa and Tabulata, have been important reef builders through much of the Phanerozoic since the Ordovician Period. However, other organism groups, such as calcifying algae members of the red algae Rhodophyta, molluscs have created massive structures at various times.
During the Cambrian Period, the conical or tubular skeletons of Archaeocyatha, an extinct group of uncertain affinities, built reefs. Other groups, such as the Bryozoa have been important interstitial organisms, living between the framework builders; the corals which build reefs today, the Scleractinia, arose after the Permian–Triassic extinction event that wiped out the earlier rugose corals, became important reef builders throughout the Mesozoic Era. They may have arisen from a rugose coral ancestor. Rugose corals built their skeletons of calcite and have a different symmetry from that of the scleractinian corals, whose skeletons are aragonite. However, there are some unusual examples of well-preserved aragonitic rugose corals in the late Permian. In addition, calcite has been reported in the initial post-larval calcification in a few scleractinian corals. Scleractinian corals may have arisen from a non-calcifying ancestor independent of the rugosan corals. One useful definition distinguishes reefs from mounds as follows: Both are considered to be varieties of organosedimentary buildups – sedimentary features, built by the interaction of organisms and their environment, that have synoptic relief and whose biotic composition differs from that found on and beneath the surrounding sea floor.
Reefs are held up by a macroscopic skeletal framework. Coral reefs are an example of this kind. Corals and calcareous algae grow on top of one another and form a three-dimensional framework, modified in various ways by other organisms and inorganic processes. By contrast, mounds lack a macroscopic skeletal framework. Mounds are built by organisms that don't grow a skeletal framework. A microbial mound might be built or by cyanobacteria. Examples of biostromes formed by cyanobacteria occur in the Great Salt Lake in Utah, in Shark Bay on the coast of Western Australia. Cyanobacteria do not have skeletons, individuals are microscopic. Cyanobacteria can encourage the precipitation or accumulation of calcium carbonate to produce distinct sediment bodies in composition that have relief on the seafloor. Cyanobacterial mounds were most abundant before the evolution of shelly macroscopic organisms, but they still exist today. Bryozoans and crinoids, common contributors to marine sediments during the Mississippian, for instance, produced a different kind of mound.
Bryozoans are small and the skeletons of crinoids disintegrate. However and crinoid meadows can persist over time and produce compositionally distinct bodies of sediment with depositional relief; the Proterozoic Belt Supergroup contains evidence of possible microbial mat and dome structures similar to stromatolite reef complexes. Benjamin Kahn Coral reef Reef Hobbyist Magazine Placer Pseudo-atoll Shears N. T. Biogeography, community structure and biological habitat types of subtidal reefs on the South Island West Coast, New Zealand. Science for Conservation 281. P 53. Department of Conservation, New Zealand. Reef Rescue - Smithsonian Ocean Portal Coral Reefs of the Tropics: facts and movies from The Nature Conservancy NOAA Photo Library Reef Environmental Education Foundation NOS Data Explorer - A portal to obtain NOAA National Ocean Service data Reef formation Atoll
Queensland is the second-largest and third-most populous state in the Commonwealth of Australia. Situated in the north-east of the country, it is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Pacific Ocean. To its north is the Torres Strait, with Papua New Guinea located less than 200 km across it from the mainland; the state is the world's sixth-largest sub-national entity, with an area of 1,852,642 square kilometres. As of 15 May 2018, Queensland has a population of 5,000,000, concentrated along the coast and in the state's South East; the capital and largest city in the state is Australia's third-largest city. Referred to as the "Sunshine State", Queensland is home to 10 of Australia's 30 largest cities and is the nation's third-largest economy. Tourism in the state, fuelled by its warm tropical climate, is a major industry. Queensland was first inhabited by Torres Strait Islanders.
The first European to land in Queensland was Dutch navigator Willem Janszoon in 1606, who explored the west coast of the Cape York Peninsula near present-day Weipa. In 1770, Lieutenant James Cook claimed the east coast of Australia for the Kingdom of Great Britain; the colony of New South Wales was founded in 1788 by Governor Arthur Phillip at Sydney. Queensland was explored in subsequent decades until the establishment of a penal colony at Brisbane in 1824 by John Oxley. Penal transportation ceased in 1839 and free settlement was allowed from 1842; the state was named in honour of Queen Victoria, who on 6 June 1859 signed Letters Patent separating the colony from New South Wales. Queensland Day is celebrated annually statewide on 6 June. Queensland was one of the six colonies which became the founding states of Australia with federation on 1 January 1901; the history of Queensland spans thousands of years, encompassing both a lengthy indigenous presence, as well as the eventful times of post-European settlement.
The north-eastern Australian region was explored by Dutch and French navigators before being encountered by Lieutenant James Cook in 1770. The state has witnessed frontier warfare between European settlers and Indigenous inhabitants, as well as the exploitation of cheap Kanaka labour sourced from the South Pacific through a form of forced recruitment known at the time as "blackbirding"; the Australian Labor Party has its origin as a formal organisation in Queensland and the town of Barcaldine is the symbolic birthplace of the party. June 2009 marked the 150th anniversary of its creation as a separate colony from New South Wales. A rare record of early settler life in north Queensland can be seen in a set of ten photographic glass plates taken in the 1860s by Richard Daintree, in the collection of the National Museum of Australia; the Aboriginal occupation of Queensland is thought to predate 50,000 BC via boat or land bridge across Torres Strait, became divided into over 90 different language groups.
During the last ice age Queensland's landscape became more arid and desolate, making food and other supplies scarce. This led to the world's first seed-grinding technology. Warming again made the land hospitable, which brought high rainfall along the eastern coast, stimulating the growth of the state's tropical rainforests. In February 1606, Dutch navigator Willem Janszoon landed near the site of what is now Weipa, on the western shore of Cape York; this was the first recorded landing of a European in Australia, it marked the first reported contact between European and Aboriginal Australian people. The region was explored by French and Spanish explorers prior to the arrival of Lieutenant James Cook in 1770. Cook claimed the east coast under instruction from King George III of the United Kingdom on 22 August 1770 at Possession Island, naming Eastern Australia, including Queensland,'New South Wales'; the Aboriginal population declined after a smallpox epidemic during the late 18th century. In 1823, John Oxley, a British explorer, sailed north from what is now Sydney to scout possible penal colony sites in Gladstone and Moreton Bay.
At Moreton Bay, he found the Brisbane River. He established a settlement at what is now Redcliffe; the settlement known as Edenglassie, was transferred to the current location of the Brisbane city centre. Edmund Lockyer discovered outcrops of coal along the banks of the upper Brisbane River in 1825. In 1839 transportation of convicts was ceased, culminating in the closure of the Brisbane penal settlement. In 1842 free settlement was permitted. In 1847, the Port of Maryborough was opened as a wool port; the first free immigrant ship to arrive in Moreton Bay was the Artemisia, in 1848. In 1857, Queensland's first lighthouse was built at Cape Moreton. A war, sometimes called a "war of extermination", erupted between Aborigines and settlers in colonial Queensland; the Frontier War was notable for being the most bloody in Australia due to Queensland's larger pre-contact indigenous population when compared to the other Australian colonies. About 1,500 European settlers and their alli