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45-402: The Basin covers approximately 507,000 km of which approximately 430,000 km is on land. It has been recognised as having prospective oil and gas capacity and has been studied extensively; as of June 2003 250 wells have been drilled and 78,000 km of seismic shot. The basin is also a distinct physiographic province of the larger West Australian Shield division. The Canning Basin

90-407: A shield that occupies more than half of the continent of Australia. The word shield is used because it refers to ancient, molten rock which has cooled and solidified. The Australian Shield has a characteristic depth of 4.5 kilometres (2.8 mi) and an estimated age of 2.8 to 3.5 billion years. In places younger sedimentary rock covers the shield's Precambrian surface. It occupies

135-539: A considerable Tertiary and younger sedimentary veneer of palaeochannel deposits derived from prolonged erosion, sedimentation and redeposition of older cover sequences and regolith as well as the Archaean basement itself. Recognised Tertiary cover sequences include the Bremer Basin , Officer Basin and others. The Yilgarn craton is believed to have remained at or above sea level for a considerable length of time. Some of

180-399: A fluid and/or metal source, or simply reflect a favourable pathway. The greater Kambalda district hosts a world-class nickel-sulfide mining district with a total pre-mining resource of 2 megatons (Mt) of nickel metal. Approximately 1.1 Mt of nickel metal has been produced since 1967, at an average rate of 35,000 tons of nickel per year. The Kambalda Dome is located in the south-central part of

225-744: A late phase that resulted in deposition and deformation of the Diemals Formation. Subsequent orogeny (ca. 2680–2655 Ma) resulted in shear zones and arcuate structures. The lithostratigraphy of the Marda–Diemals greenstone belt are similar to the northern Murchison Terrane, but has older greenstones and deformation events than the southern Eastern Goldfields Terrane. This indicates that the Eastern Goldfields Terrane may have accreted to an older Murchison–Southern Cross granite–greenstone nucleus. The Archaean Norseman-Wiluna Greenstone Belt in

270-482: A location in Western Australia is a stub . You can help Misplaced Pages by expanding it . This article about a specific Australian geological feature is a stub . You can help Misplaced Pages by expanding it . Australian Shield 26°00′00″S 129°00′00″E  /  26.00007744°S 129.00005163°E  / -26.00007744; 129.00005163 The Australian Shield is a geological feature known as

315-638: A middle Proterozoic mobile belt which leads east to the Musgrave Block . The Gascoyne complex and other metamorphic belts of this age including reactivation of the Yarlarweelor Gneiss and Narryer Gneiss Terrane , indicate prolonged multi-phased strike-slip movement (relative to the Yilgarn Craton margin) from the late Archaean through to neoproterozoic and even into the Palaeozoic. The Yilgarn Craton

360-777: A significant pulse of greenhouse gases, as the age broadly overlaps with the youngest glacial deposits. The Southern Cross Province lies in the central area of the Yilgarn craton. The Marda–Diemals greenstone belt in the Southern Cross Terrane can be divided into three layers: the lower greenstone belt (ca. 3.0 Ga) characterized by mafic volcanic rock and banded iron formation, a felsic-intermediate volcanism layer, and an upper sedimentary layer (ca. 2.73 Ga) of calc-alkaline volcanic (Marda Complex) and clastic sedimentary rocks ( Diemals Formation ). East–West orogeny (ca. 2730–2680 Ma) occurred in two stages; an earlier folding phase and

405-481: A stratigraphical drilling party (1955-58). All work was based on air photographs, at a scale of 1:50,000, prepared by the R.A.A.F. This bulletin incorporates the results of all these surveys. The first attempt at compiling a geology of the Canning Basin was made by Reeves in 1949 18°11′15″S 124°18′37″E  /  18.18750°S 124.31028°E  / -18.18750; 124.31028 This article about

450-742: Is a western part of the Australian Shield. The Australian Shield is fractured into a number of distinct blocks , including two cratons - the Pilbara Craton in the North and the Yilgarn Craton in the Southwest. These two cratons are the oldest part of the shield, both of which have been dated at more than 2.3 billion years old. Some of these blocks have been raised to form uplands; others have been depressed, forming lowlands and basins. The lowlands include

495-411: Is bounded on the east-southeast by the ~1,300 Ma Albany-Fraser Orogen , composed primarily of amphibolite to greenschist facies sedimentary protolith gneisses, migmatites and granites. The Albany-Fraser Orogen displays both subduction-related and prolonged strike-slip tectonic structures and is intimately interconnected with the other Proterozoic basins and mobile belts of Australia. The Yilgarn Craton

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540-558: Is considered to be peak granulite facies, but the majority has preserved peak amphibolite facies assemblages. In total, the Western Gneiss Terrane sub-blocks represent an earlier substrate upon which the majority of the Yilgarn Craton's about 2.70 to 2.55 Ga greenstone metavolcanic belts have been deposited and into which the voluminous Archaean trondhjemite-tonalite-granodiorite suite and trondhjemite - tonalite - diorite suite granites were emplaced. The Murchison Province

585-409: Is considered to have been produced during Caenozoic to Palaeocene tropical conditions, as evidenced by mottled duricrust which records fossilised tree roots, some over 60 million years old. Previous weathering events have been recorded in magnetically remnant ferruginous laterite of a Jurassic age, at about 180 Ma. The regolith of the Yilgarn impacts directly on the flora and fauna, as some of

630-423: Is currently recovered from several areas in the Yilgarn Craton, although it is a much smaller set of mines than those in the Pilbara Craton . Iron ore is mined at Koolyanobbing, north of Kalgoorlie from hematite weathered banded iron formation , at Mount Gibson, Weld Range and Jack Hills in the Western Gneiss Terrane from hematite banded iron formation to produce direct-shipping ore. The Karara Iron Ore Project

675-632: Is distinct from the remainder of the Yilgarn Craton in that the latter has a predominance of metavolcanic rocks, both felsic and mafic , whereas the former consists of high-grade metasediments and gneisses of unknown protolith . The Western Gneiss Terrane is exposed along the western half of the northern margin of the Yilgarn Craton as the Narryer Gneiss Terrane , a composite of heavily polydeformed feldspathic metagranite and metasedimentary amphibolite -grade gneisses and migmatites , dated at greater than 3.3 Ga and up to 3.8 Ga in age, flanked by

720-532: Is exposed in the western and northern third of the Yilgarn Craton. The Province is bounded by major transcrustal structures which separate it from the surrounding tectonic provinces of the craton and the Western Gneiss Belt. The Murchison Province Stratigraphy, after Watkins (1990), is divided into six basic structural-stratigraphic components - two greenstone belt metavolcanic-metasedimentary sequences and four suites of granitoids. The structural framework in

765-472: Is home to a Devonian fossil reef complex that stretches 350 km across the northern edge of the basin. The fossil reef is very well preserved and is cut by several modern canyons, including Geikie Gorge and Windjana Gorge . The fossil sites associated the ancient reef system that extended for around one thousand kilometres along what is now the northwest of the Australian continent, described as resembling

810-599: Is one of the distinct physiographic provinces of the West Australian Shield physiographic division, which comprises the Stirling-Mount Barren Block, Darling Hills, and Recherche Shelf sections. The Western Gneiss Terrane is a series of polydeformed high-grade early Archaean metamorphic belts, composed predominantly of feldspathic leucocratic granulite gneisses, which represent some of the oldest crustal fragments on Earth. The Western Gneiss Terrane

855-646: Is partially covered by onlapping sedimentary basins of Palaeozoic and Phanerozoic age in the east and north-east, including the Canning Basin . It is bounded on the western edge by the Darling Scarp and Darling Fault which separate the Yilgarn Craton from the Perth Basin to the west, and is covered by several remnant sedimentary basins of Jurassic age such as the Collie Sub-Basin. The Yilgarn Craton also has

900-599: Is primarily composed of approximately 2.8 billion year old (~2.8 Ga) granite-gneiss metamorphic terrain (the Southwestern Province and Western Gneiss Belt), and three granite- greenstone terrains (the North-East Goldfields, the Southern Cross and the greenschist metamorphic Murchison Provinces). Some greenstone belts and granites are as old as 3.1-2.9 Ga, and some are younger, at ~2.75-2.65 Ga. The craton

945-569: Is the only operational magnetite mine in the Yilgarn Craton, however, other magnetite iron ore deposits are being investigated as a source of magnetite ore in the Albany-Fraser Complex, where a large deposit is being proposed at Southdown. The Jack Hills, Weld Range and Mount Gibson banded iron formations, as well as banded iron formations around Yalgoo , are also considered potential sources of magnetite iron ore, although no operations are as yet running on this type of ore. Further away from

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990-877: The Great Sandy Desert , the Gibson Desert , the Great Victoria Desert and the Nullarbor Plain , which are located in the north-western, central, southern and south-eastern shield areas respectively. The Nullarbor (from Latin, “no trees”) is an arid, virtually uninhabited limestone plateau. Between the Western Australian Shield and the Great Dividing Range is the Great Artesian Basin region. The uplands include, in Western Australia ,

1035-665: The Hamersley and Wunaamin-Miliwundi ranges in the western and north-western coastal areas and the Darling Range inland from Perth in the far south-west. The MacDonnell Ranges lie in the southern part of the Northern Territory and the Stuart and Musgrave Ranges are located in the north of the state of South Australia. Erosion and weathering have created striking, isolated rock formations called mesas or buttes in many parts of

1080-536: The Yarrabubba crater , which is the oldest dated meteorite impact crater , at 2229 ± 5 Ma . The crater is heavily eroded and no surface expression remains of the original structure. The primary trace is an elliptical aero- magnetic anomaly , measuring approximately 20 km by 11 km, as well as the presence of shock-recrystallised minerals. This impact may have ended the Huronian glaciation by climate forcing with

1125-472: The Archaean Norseman-Wiluna greenstone belt in the southeastern Yilgarn Craton. Kambalda type komatiitic nickel ore deposits are the primary source of nickel metal within the Yilgarn Craton. Copper, lead and zinc are currently mined from Golden Grove and the newly developed Jaguar zinc mine . Minor amounts of copper have been recovered from several copper-bearing gold deposits such as those in

1170-648: The Eastern Goldfield Province contains most of Australia's lode gold deposits, including the famous Kalgoorlie Golden Mile containing the Super Pit . These gold deposits are generally of large tonnage and are confined to the volcanic-intrusive-sedimentary sequences of the greenstone belts and not the granites. There is a pattern of gold distribution along the Archean Boulder-Lefroy shear zone. Extrusive komatiites (ultramafic volcanic rocks) occur along

1215-555: The Gullewa Greenstone Belt, at Burtville south of Laverton, at Granny Smith and elsewhere. The desert area encircling Kalgoorlie, with an area of 500,000 square kilometres, is theorised to host a 100 million tonne copper-zinc deposit. The geology of several volcanic belts in the Yilgarn Craton are strikingly similar to the world's great base-metal mines at Kidd Creek in Northern Ontario , Canada . Exploration for copper

1260-696: The Jimperding Gneiss Complex range in age from 3267 ± 30 Ma to 3341 ± 100 Ma, with metamorphic overgrowth dated at 3180 Ma. On the southwest of the Yilgarn Craton the Balingup Gneiss Complex is situated inboard from the Early Proterozoic Leeuwin Complex of metamorphic rocks. The Balingup Complex consists primarily of metasedimentary paragneiss, granite orthogneiss, with minor layers of calc-silicate , ultramafic and ortho-amphibolite gneiss. The metamorphic grade

1305-786: The Murgoo Gneiss Terrane (2.95 Ga), as well as sheets of 2.75 Ga to 2.6 Ga granite, obducted ophiolite sheets (the Trillbar Complex) and some 2.4 Ga to 2.0 Ga Proterozoic gneiss belts. On the western edge of the Yilgarn Craton, partially covered by Phanerozoic sedimentary basins and in faulted contact with the 2.7 Ga to 2.55 Ga Yilgarn tectonic domains, lies the Jimperding Gneiss Complex of 2.75 to 2.65 Ga age, composed primarily of micaceous quartzite , quartz-feldspar-biotite-garnet gneiss, andalusite and sillimanite schists , banded iron formation and other exotics, intruded by minor masses of porphyritic granite. Detrital zircons in

1350-502: The Norseman-Wiluna Greenstone Belt. A change from volcanic-dominated to plutonic-dominated magmatism occurred in the Norseman-Wiluna Greenstone Belt approximately 2685–2675 Ma. Voluminous high-Ca granite intrusions occurred 2670–2655 Ma. Much of the gold was deposited between 2650–2630 Ma, with much of this associated with strike-slip reactivation of earlier faults (normal and reverse). An earlier gold event 2660-2655 Ma

1395-520: The Yilgarn regolith is the oldest in the world, recording weathering events as early as the Cretaceous Period. This has been created by the generally subtropical latitudes and conditions of the Yilgarn craton, with minimal to no glaciation and generally flat topographical relief resulting in comparatively minor erosion. The regolith is extremely deeply weathered, in some areas completely converted to saprolite up to 100 metres below surface. This

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1440-420: 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 accretion events occurred in several phases, probably by accretion of continental fragments separated by pauses in subduction , with renewed activity occurring episodically. The craton

1485-614: The coast, deposits of banded iron formation at Wiluna and Laverton are also under investigation, although infrastructure is considered too poor to render these deposits economic. The Yilgarn Craton is host to around 4% of the world's economically demonstrably recoverable reserves (EDR) of gold. Major gold deposits occur at Kalgoorlie, Kambalda, Mount Magnet, Boddington, Laverton and Wiluna, and are hosted in greenstone belts. These form linear belts of mafic, ultramafic and felsic volcanics, intercalated with sedimentary sequences, and have been deformed and metamorphosed. The mode of occurrence of

1530-482: The craton contains the Yarrabubba impact structure , at over 2 billion years old it is the oldest dated meteorite impact crater . 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

1575-520: The discovery of the Gogo fish. The internal features of the basin include: The Australian Bureau of Mineral Resources report of the geology of the basin outlines the early exploration: The Bureau started field work in the Canning Basin in 1947 and continued every year up to 1958. This work was carried out by geological parties equipped with land vehicles (1947-56) and with a helicopter (1957), by seismic and gravity parties, by an airborne magnetic party, and by

1620-504: The gold mineralisation tends to be small- to medium-sized structurally controlled lodes, shears, and quartz veins. A key feature beneath many of the region's gold deposits are granite-cored domes at a range of scales. These provided an architecture that focussed fluid metals into the upper crust's depositional sites. Signatures of the mantle are found in many large deposits, including melts from metasomatised mantle wedge as well as lamprophyres. Debate continues whether these mantle rocks were

1665-457: The modern Great Barrier Reef off the coast of Eastern Australia. The sites have produced ancient fossil material in an excellent state of preservation, most notably those revealing details of the structure of skeletons and soft-tissues of early amphibians. One important site is referred to as the "Devonian 'Great Barrier Reef'", and another, the "Gogo fish fossil site" (the Gogo formation ), is named for

1710-416: The northeastern Yilgarn craton was largely shaped by transpression that led to the development of folds, reverse faults, sinistral strike-slip movement on NNW-trending regional shear zones, followed by regional folding and shortening. The later occurred in overlapping tectonic processes. The first deformation event is poorly understood but appears to have involved N-S thrusting. The Murchison Province contains

1755-646: The portion of Australia west of a line running north–south roughly from the eastern shore of Arnhem Land on the Bay or Gulf of Carpentaria to the Eyre Peninsula in the state of South Australia , and skirting to the west of the Simpson Desert in the interior. The plateau has an average elevation of between 305 and 460 m (1,001 and 1,509 ft). The geological region called the Western Australian Shield

1800-589: The post-Archaean events which have involved the Yilgarn Craton. The Yilgarn Craton is bound on the western side by the Perth Basin , of Jurassic age, and is separated from this basin by the Darling Fault . The Perth Basin is considered to be a rift fill basin formed on a passive margin. The Perth Basin is bound on the north by the Gascoyne Complex , Glengarry Basin and Yerrida Basin , which are all part of

1845-457: The salt behind. The greenstone belts of the Yilgarn Craton include: The Yilgarn Craton is Australia's premier mineral province. It attracts more than half of Australia's minerals exploration expenditure, and produces two thirds of all gold and most of the nickel mined in Australia. The craton contains some 30% of the world's known gold reserves, about 20% of the world's nickel reserves, 80% of

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1890-750: The shield, including the Kimberleys and Pilbara districts of Western Australia and Arnhem Land in the Northern Territory. Yilgarn Craton The Yilgarn Craton is a large craton that constitutes a major part 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

1935-415: The soil is essentially fossilised. Much of the groundwater of the Yilgarn is hypersaline, with some being supersaturated in salt. This renders swathes of land barren, with significant salt lakes, and high saline water tables. The origin of this salt is thought to be from precipitation of sea salt carried over the Australian landmass for the past several dozen million years, and the high evaporation rate leaving

1980-594: The world's tantalum reserves, considerable iron ore , copper , zinc and minor lead reserves. The craton contains significant platinum , vanadium , hard-rock titanium and considerable iron ore resources. Mining is conducted mostly in the greenstone belts around mining centres such as Kalgoorlie , Kambalda , Norseman , Meekatharra and Wiluna , and minor centres such as Laverton , Leinster , Leonora and Southern Cross . Ore concentrates or finished product are transported by rail or road to Perth , Fremantle , Esperance , Albany or Geraldton . Iron ore

2025-444: Was associated with major extension (normal faulting and granite doming) resulting in the formation of late basins and the intrusion of mantle-derived magmas (syenites and Mafic-type granites/porphyries) and tight anticlockwise PTt paths. The Yilgarn Craton is bound on all sides by younger terranes of various ages, but predominantly of Proterozoic age. The boundaries between the various flanking terranes provide considerable evidence of

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