The Great Artesian Basin provides the only reliable source of water through much of inland Australia. Lightning Ridge is a town in north-western New South Wales, Australia, in Walgett Shire, near the southern border of Queensland. The township of Thargomindah is located in south west Queensland, Australia on the Adventure Road, approximately 1100 km west of the state capital Water is a common Chemical substance that is essential for the survival of all known forms of Life. For a topic outline on this subject see List of basic Australia topics. The basin is the largest and deepest artesian basin in the world. See Great Artesian Basin for the water source in Australia An artesian aquifer is a confined aquifer containing Groundwater It underlies 23% of the continent, including most of Queensland, the south-east corner of the Northern Territory, the north-east part of South Australia, and northern New South Wales. Queensland is a state of Australia, occupying the north-eastern corner of the mainland continent The Northern Territory is a federal territory of Australia, occupying much of the center of the mainland continent as well as the central northern regions South Australia is a state of Australia in the southern central part of the country The basin is 3000 metres (10,000 ft) deep in places and is estimated to contain 64,900 cubic kilometres of groundwater. Groundwater is Water located beneath the Ground surface in Soil pore spaces and in the Fractures of lithologic formations [1] The Great Artesian Basin Coordinating Committee (GABCC) [1] coordinates activity between the various levels of government and community organisations.
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Physiography
This area is one of the distinct physiographic provinces of the larger East Australian Basins division, and includes the smaller Wilcannia Threshold physiographic section.
Geology
The water of the GAB is held in a sandstone layer laid down by continental erosion of higher ground during the Triassic, Jurassic, and early Cretaceous periods. The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago The Jurassic is a geologic period and system that extends from about Ma (million years ago to Ma that is from the end of the Triassic to the beginning The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of During a time when much of what is now inland Australia was below sea level, the sandstone was then covered by a layer of marine sedimentary rock shortly afterwards, which formed a confining layer - thus trapping water in the sandstone aquifer. Mean sea level (MSL is the average (mean height of the Sea, with reference to a suitable reference surface The eastern edge of the basin was uplifted when the Great Dividing Range formed. Tectonic uplift is a geological process most often caused by Plate tectonics which increases elevation The Great Dividing Range, also known as the Eastern Highlands, is Australia 's most substantial Mountain range. The other side was created from the landforms of the Central Eastern Lowlands and the Great Western Plateau to the west. The Western Plateau is Australia 's largest drainage division and is composed predominantly of the remains of the ancient rock shield of Gondwanaland.
Most recharge water enters the rock formations from relatively high ground near the eastern edge of the basin (in Queensland and New South Wales) and very gradually flows towards the south and west. (A much smaller amount enters along the western margin in arid central Australia, flowing to the south and east. ) Because the sandstones are permeable, water gradually makes its way through the pores between the sand grains, flowing at a rate of one to five metres per year. Sand is a naturally occurring Granular material composed of finely divided rock and Mineral particles
Discharge water eventually exits through a number of springs and seeps, mostly in the southern part of the basin. A spring is a point where Groundwater flows out of the ground and is thus where the Aquifer surface meets the ground surface It takes up to two million years for water to travel to the springs in the Lake Eyre area. Lake Eyre (pronounced "air" is the lowest point in Australia, at approximately ( AHD) below sea level and on the rare occasions that it fills the
Water source
Prior to European occupation, waters of the GAB discharged through mound springs, many in arid South Australia. These springs supported a variety of endemic invertebrates (molluscs, for example). After European occupation, the Great Artesian Basin became an important water supply for cattle raising, irrigation, and stock and domestic usage, and is a vital life line for rural Australia. A ranch is an area of landscape including various structures given primarily to the practice of ranching the practice of raising grazing livestock such as Cattle Irrigation is an artificial application of water to the soil usually for assisting in growing crops Software for Fixed assets management and Stock control developed in 2004. To tap it, bores are drilled down to a suitable rock layer, where the pressure of the water forces it up, mostly without pumping. For information on Wikipedia project-related discussions see WikipediaVillage pump.
The discovery and use of water held underground in the Great Artesian Basin opened up thousands of square miles of country in inland New South Wales, Queensland and South Australia, previously unavailable for pastoral activities. European discovery of the basin dates from 1878 when a shallow bore near Bourke, New South Wales produced flowing water. Bourke is a town and Local Government Area (see Bourke Shire Council) in the north of New South Wales, Australia. There were similar discoveries in 1886 at Back Creek east of Barcaldine, Queensland, and in 1887 near Cunnamulla, Queensland. Barcaldine is a small town and Local Government Area located in Western Queensland, Australia, approximately 520 kilometres by road west of the city Cunnamulla ( Aboriginal meaning "dry water hole" is a small town which lies on the Warrego River in south west Queensland, Australia [2]
Water extraction from the GAB is essentially a mining operation, with recharge much less than current extraction rates. In 1983 there were close to 18 000 bores providing 1575 million litres of water. This included just under 2000 freely flowing bores and more than 9000 that required mechanical power to bring water to the surface. In Physics and Engineering, mechanical advantage (MA is the factor by which a mechanism multiplies the force put into it Many bores are unregulated or abandoned, resulting in considerable water wastage. The Australian Commonwealth Government announced additional funding in January 2007 in an attempt to bring these problems, which have existed for many decades, under control. Unfortunately, many of the mound springs referred to above have dried up due to a drop in water pressure, resulting in extinction of several invertebrate species.
Additionally, the basin has provided water via a 1. 2 km deep bore for a geothermal power station at Birdsville. Geothermal power (from the Greek roots geo, meaning earth and therme, meaning heat is energy generated by heat stored in the earth or the collection Birdsville is a small town located in Western Queensland, Australia. The heated water is 98 °C (208 °F) and provides 25% of the towns needs. Ergon Energy is expanding the 80 kW plant to completely meet Birdville's electricity requirements. Ergon is a corporation owned by the Government of Queensland.
Whole of Basin Management
As the Great Artesian Basin underlies parts of Queensland, New South Wales, South Australia and the Northern Territory, which each operate under different legislative frameworks, policies and resource management approaches, a coordinated "whole-of-Basin" approach to the management of this important natural resource is required. The Great Artesian Basin Coordinating Committee (GABCC) provides advice from community organisations and agencies to State, Territory and Australian Government Ministers on efficient, effective and sustainable whole-of-Basin resource management and to coordinate activity between stakeholders.
Membership of the Committee comprises all State, Territory and Australian Government agencies with responsibilities for management of parts of the Great Artesian Basin, community representatives nominated by agencies; and sector representatives. The primary role of the Committee is to provide advice to State, Territory and Australian Government Ministers on efficient, effective and sustainable whole-of-Basin resource management and to coordinate activity between stakeholders.
The GABCC website provides up to date information and links regarding the Great Artesian Basin and can be accessed through their website www. gabcc. org. au [2].
Current scientific thinking
A comprehensive background to the Great Artesian Basin, including an overview of the nature of the Basin, the extraction of water and the impacts of that extraction, can be found in the Great Artesian Basin Resource Study, developed by the GABCC to support the Great Artesian Basin Strategic Management Plan.
External links
- [3] L. A. Endersbee, "A New Understanding of the Groundwater Resources of the Great Artesian Basin", Australian Academy of Technological Sciences and Engineering
References
- ^ The Great Artesian Basin (PDF). Facts: Water Series. Queensland Department of Natural Resources and Water. Retrieved on 2007-01-03. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1431 - Joan of Arc is handed over to the Bishop Pierre Cauchon.
- ^ Nicol, Sally (2005). The Great Artesian Basin: past, present and future. Water management. The State of Queensland (Department of Natural Resources and Water). Retrieved on 2007-03-02. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 986 - Louis V becomes King of the Franks. 1127 - Assassination of Charles the Good