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Eastern Mallee
Eastern Mallee is an Interim Biogeographic Regionalisation for Australia (IBRA) subregion in southern Western Australia. Geography Eastern Mallee is roughly defined as the eastern half of the Mallee biogeographic region. It has an area of around 46,000 square kilometres, and is very sparsely populated. The only towns occur along the road from Esperance to Norseman. The largest and best known town is Salmon Gums; others include Scaddan, Grass Patch, Red Lake and Dowak, Western Australia. Watercourses in the area include Young River, Lort River, Oldfield River and Jerdacuttup River. Drainage is occluded, however, and the area has numerous salt pans. Geology Situated on the south-eastern edge of the Yilgarn Craton, Eastern Mallee has a gently undulating landscape. It has a variety of surface types, including calcareous clays and loams containing kankar; outcrops of metamorphosed sandstone; white and yellow sand; and loamy pan fields. Gypsum dunes also occur in the area. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBRA 6
The Interim Biogeographic Regionalisation for Australia (IBRA) is a biogeographic regionalisation of Australia developed by the Australian government's Department of Sustainability, Environment, Water, Population, and Communities. It was developed for use as a planning tool, for example for the establishment of a national reserve system. The first version of IBRA was developed in 1993–94 and published in 1995. Within the broadest scale, Australia is a major part of the Australasia biogeographic realm, as developed by the World Wide Fund for Nature. Based on this system, the world is also split into 14 terrestrial habitats, of which eight are shared by Australia. The Australian land mass is divided into 89 bioregions and 419 subregions. Each region is a land area made up of a group of interacting ecosystems that are repeated in similar form across the landscape. IBRA is updated periodically based on new data, mapping improvements, and review of the existing scheme. The most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yilgarn Craton
The Yilgarn Craton is a large craton that constitutes the bulk of the Western Australian land mass. It is bounded by a mixture of sedimentary basins and Proterozoic fold and thrust belts. Zircon grains in the Jack Hills, Narryer Terrane have been dated at ~4.27 Ga, with one detrital zircon dated as old as 4.4 Ga. The Murchison Province of the craton contains the oldest dated meteorite impact crater, at 2229 ± 5 Ma. Geology The Yilgarn Craton appears to have been assembled between ~2.94 and 2.63 Ga by the accretion of a multitude of formerly present blocks or terranes of existing continental crust, most of which formed between 3.2 Ga and 2.8 Ga. This accretion event is recorded by widespread granite and granodiorite intrusions, which comprise over 70% of the Yilgarn craton; voluminous tholeiitic basalt and komatiite volcanism; regional metamorphism and deformation as well as the emplacement of the vast majority of the craton's endowment in gold mineralisation. These acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucalyptus
''Eucalyptus'' () is a genus of over seven hundred species of flowering trees, shrubs or mallees in the myrtle family, Myrtaceae. Along with several other genera in the tribe Eucalypteae, including '' Corymbia'', they are commonly known as eucalypts. Plants in the genus ''Eucalyptus'' have bark that is either smooth, fibrous, hard or stringy, leaves with oil glands, and sepals and petals that are fused to form a "cap" or operculum over the stamens. The fruit is a woody capsule commonly referred to as a "gumnut". Most species of ''Eucalyptus'' are native to Australia, and every state and territory has representative species. About three-quarters of Australian forests are eucalypt forests. Wildfire is a feature of the Australian landscape and many eucalypt species are adapted to fire, and resprout after fire or have seeds which survive fire. A few species are native to islands north of Australia and a smaller number are only found outside the continent. Eucalypts have been grow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mallee Woodlands And Shrublands
Mallee Woodlands and Shrublands is one of 32 Major Vegetation Groups defined by the Australian Government Department of the Environment and Energy. Description " Mallee" refers to the growth habit of a group of (mainly) eucalypt species that grow to a height of , have many stems arising from a lignotuber and have a leafy canopy that shades 30–70% of the ground. The term is also applied to a vegetation association where these mallee eucalypts grow, on land that is generally flat without hills or tall trees and where the climate is semi-arid. Of the 32 Major Vegetation Groups classified under the National Vegetation Information System, "Mallee Woodlands and Shrublands" (MVG14): * are semi-arid areas dominated by mallee eucalypts; * may also have co-dominant species of '' Callitris'', '' Melaleuca'', ''Acacia'' and ''Hakea''; * have an open tree or shrub layer with more than 10% foliage cover and more than 20% crown cover, distinguishing MVG 14 from "Mallee Open Woodland" (MVG14 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Johnston Gnangarra
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediterranean Climate
A Mediterranean climate (also called a dry summer temperate climate ''Cs'') is a temperate climate sub-type, generally characterized by warm, dry summers and mild, fairly wet winters; these weather conditions are typically experienced in the majority of Mediterranean-climate regions and countries, but remain highly dependent on proximity to the ocean, altitude and geographical location. This climate type's name is in reference to the coastal regions of the Mediterranean Sea within the Mediterranean Basin, where this climate type is most prevalent. The "original" Mediterranean zone is a massive area, its western region beginning with the Iberian Peninsula in southwestern Europe and coastal regions of northern Morocco, extending eastwards across southern Europe, the Balkans, and coastal Northern Africa, before reaching a dead-end at the Levant region's coastline. Mediterranean climate zones are typically located along the western coasts of landmasses, between roughly 30 and 45 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dune
A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes with little or no vegetation are called ''ergs'' or ''sand seas''. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter ''slip face'' in the lee side. The valley or trough between dunes is called a ''dune slack''. Dunes are most common in desert environments, where the lack of moisture hinders the growth of vegetation that would otherwise interfere with the development of dunes. However, sand deposits are not restricted to deserts, and dunes are also found along sea shores, along streams in semiarid climates, in areas of glacial outwash, and in other areas where poorly cemented sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. Alabaster, a fine-grained white or lightly tinted variety of gypsum, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison. Etymology and history The word ''gypsum'' is derived from the Greek word (), "plaster". Because the quarries of the Montmartre district of Paris have long furnished burnt gypsum (calcined gypsum) used for various purposes, this dehydrated gypsum became known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand, for example, aragonite, which has mostly been created, over the past 500million years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Somewhat more rarely, sand may be composed of calciu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, fish, amphibians, mollusks, crustaceans, cnidarians, echinoderms, and tunicates undergo metamorphosis, which is often accompanied by a change of nutrition source or behavior. Animals can be divided into species that undergo complete metamorphosis (" holometaboly"), incomplete metamorphosis ("hemimetaboly"), or no metamorphosis (" ametaboly"). Scientific usage of the term is technically precise, and it is not applied to general aspects of cell growth, including rapid growth spurts. Generally organisms with a larva stage undergo metamorphosis, and during metamorphosis the organism loses larval characteristics. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kankar
{{unreferenced, date=April 2008 Kankar or kunkur is a sedimentological term derived from Hindi, occasionally applied in India and the United States to detrital or residual rolled, often nodular calcium carbonate formed in soils of semi-arid regions. It forms sheets across alluvial plains and can occur as discontinuous lines of nodular kankar or as indurated layers in stratigraphic profiles more commonly referred to as calcrete, hardpan or duricrust. See also * Caliche (mineral) Image:Kankar_sheet.jpg, Recent kankar sheet on Hookina Floodplain, South Australia Image:Kankar_channel_fill.jpg, Late Pleistocene kankar channel fill and lines in riverbank section of Hookina Floodplain, South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ... Sedimentology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders_Quarry-1.jpg "Click for more on -> Sandstone")
