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Dangerous Reef
Dangerous Reef is an island and reef system located in the Spencer Gulf in the Australian state of South Australia about east-southeast of the city, Port Lincoln. It is the southernmost member of the Sir Joseph Banks Group. It has been the site of a navigation aid since 1911. It is notable as the site of a breeding colony of Australian sea lions. The waters adjoining its shore are notable as a place to view great white sharks to the extent that it was both a popular gamefishing and shark cage diving venue during the twentieth century, and was used to film footage for the following motion pictures – ''Blue Water White Death'' and ''Jaws''. The island has enjoyed protected area status since 1900 and it has been part of the Sir Joseph Banks Group Conservation Park since 1989. Description Dangerous Reef is located in Spencer Gulf about east-south east of the city of Port Lincoln, about north-northeast of Observatory Point on the northeast coast of Thistle Island and is ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sir Joseph Banks Group
The Sir Joseph Banks Group is an archipelago in the Australian state of South Australia located in Spencer Gulf about off the eastern coast of the Eyre Peninsula. It consists of 21 islands of which eighteen are in the Sir Joseph Banks Group Conservation Park while the surrounding waters are in the Sir Joseph Banks Group Marine Park. It is considered to be an important seabird seabird colony, breeding site. Description The islands are low-lying, with the highest point on Spilsby of about They consist mainly of a granite base beneath limestone and are usually capped with calcrete or sandy soil. Reevesby and Spilsby are the largest islands in the group. Spilsby Island is privately owned and continues to be grazed by sheep, as well as holding a few holiday cottages. Islands The group consists of the following islands: * Blyth Island * Boucaut Island * Buffalo Reef * Dalby Island * Dangerous Reef * Duffield Island * English Island (South Australia), English Island * Hareby I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can be used for any given locale to find the predicted times and amplitude (or "tidal range"). The predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide (pattern of tides in the deep ocean), the amphidromic systems of the oceans, and the shape of the coastline and near-shore bathymetry (see '' Timing''). They are however only predictions, the actual time and height of the tide is affected by wind and atmospheric pressure. Many shorelines experience semi-diurnal tides—two nearly equal high and low tides each day. Other locations have a diurnal tide—one high and low tide each day. A "mixed tide"—two uneven magnitude tides a day—is a third regular category. Tides va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little Tern
The little tern (''Sternula albifrons'') is a seabird of the family Laridae. It was formerly placed into the genus ''Sterna'', which now is restricted to the large white terns. The genus name is a diminutive of ''Sterna'', "tern". The specific ''albifrons'' is from Latin ''albus'', "white", and "frons", ''forehead''. The former North American (''S. a. antillarum'') and Red Sea ''S. a. saundersi'' subspecies are now considered to be separate species, the least tern (''Sternula antillarum'') and Saunders's tern (''Sternula saundersi''). This bird breeds on the coasts and inland waterways of temperate and tropical Europe and Asia. It is strongly migratory, wintering in the subtropical and tropical oceans as far south as South Africa and Australia. There are three subspecies, the nominate ''albifrons'' occurring in Europe to North Africa and western Asia; ''guineae'' of western and central Africa; and ''sinensis'' of East Asia (SE Russia to Japan, SE Asia, Philippines) and the nort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greater Crested Tern
The greater crested tern Retrieved 28 February 2012 (''Thalasseus bergii''), also called crested tern or swift tern, is a tern in the family Laridae that nests in dense colonies on coastlines and islands in the tropical and subtropical Old World. Its five subspecies breed in the area from South Africa around the Indian Ocean to the central Pacific and Australia, all populations dispersing widely from the breeding range after nesting. This large tern is closely related to the royal and lesser crested terns, but can be distinguished by its size and bill colour. The greater crested tern has grey upperparts, white underparts, a yellow bill, and a shaggy black crest that recedes in winter. Its young have a distinctive appearance, with strongly patterned grey, brown and white plumage, and rely on their parents for food for several months after they have fledged. Like all members of the genus ''Thalasseus'', the greater crested tern feeds by plunge diving for fish, usually in marine en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cormorant
Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the IOC adopted a consensus taxonomy of seven genera. The great cormorant (''Phalacrocorax carbo'') and the common shag (''Gulosus aristotelis'') are the only two species of the family commonly encountered in Britain and Ireland and "cormorant" and "shag" appellations have been later assigned to different species in the family somewhat haphazardly. Cormorants and shags are medium-to-large birds, with body weight in the range of and wing span of . The majority of species have dark feathers. The bill is long, thin and hooked. Their feet have webbing between all four toes. All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lepidium
''Lepidium'' is a genus of plants in the mustard/cabbage family, Brassicaceae. The genus is widely distributed in the Americas, Africa, Asia, Europe, and Australia.''Lepidium''. Flora of North America. It includes familiar species such as , , and dittander. General s include peppercress, peppergrass, pepperweed, and pepperwort. Som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atriplex
''Atriplex'' () is a plant genus of about 250 species, known by the common names of saltbush and orache (; also spelled orach). It belongs to the subfamily Chenopodioideae of the family Amaranthaceae ''s.l.''. The genus is quite variable and widely distributed. It includes many desert and seashore plants and halophytes, as well as plants of moist environments. The generic name originated in Latin and was applied by Pliny the Elder to the edible oraches. The name saltbush derives from the fact that the plants retain salt in their leaves; they are able to grow in areas affected by soil salination. Description Species of plants in genus ''Atriplex'' are annual or perennial herbs, subshrubs, or shrubs. The plants are often covered with bladderlike hairs, that later collapse and form a silvery, scurfy or mealy surface, rarely with elongate trichomes. The leaves are arranged alternately along the branches, rarely in opposite pairs, either sessile or on a petiole, and are sometim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaannum
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (the mean yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimban Orogeny
The Kimban orogeny, also termed the Strangways orogeny, affected the Gawler Craton in what is now Australia between 1.73 and 1.69 billion years ago in the Proterozoic. As the most widespread orogenic event in the craton's evolution, the Kimban orogeny led to widely variable metamorphism included granulite and greenschist-grade on the sequence of metamorphic facies, preserved in the Tunkillia, Moody and Middlecamp rock suites. The Moody Suite formed late in the orogeny and was intruded with hornblende-rich granitoids and muscovite-rich leucogranites. See also *List of orogenies The following is a list of known orogenies organised by continent, starting with the oldest at the top. The organization of this article is along present-day continents that do not necessarily reflect the geography contemporary to the orogenies. ... References Orogenies of Australia Proterozoic orogenies {{Australia-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite Gneiss
Gneiss ( ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures and pressures than schist. Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage. Gneisses are common in the ancient crust of continental shields. Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss. Description Orthogneiss from the Czech Republic In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding (gneissic banding) but poorly developed schistosity and indistinct cleavage. In other words, it is a metamorphic rock composed of mineral grains easily seen with the unaided eye, which form obvious compositional layers, but which has only a weak tendency to fracture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is nearly alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peneplain
390px, Sketch of a hypothetical peneplain formation after an orogeny. In geomorphology and geology, a peneplain is a low-relief plain formed by protracted erosion. This is the definition in the broadest of terms, albeit with frequency the usage of peneplain is meant to imply the representation of a near-final (or penultimate) stage of fluvial erosion during times of extended tectonic stability. Peneplains are sometimes associated with the cycle of erosion theory of William Morris Davis, but Davis and other workers have also used the term in a purely descriptive manner without any theory or particular genesis attached. The existence of some peneplains, and peneplanation as a process in nature, is not without controversy, due to a lack of contemporary examples and uncertainty in identifying relic examples. By some definitions, peneplains grade down to a base level represented by sea level, yet in other definitions such a condition is ignored. Geomorphologist Karna Lidmar-Bergstrà ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
