Gawler Ranges
| Gawler Ranges | |
|---|---|
 Columnar jointinginrhyoliteat the "Organ Pipes" waterfall in the ranges | |
| Highest point | |
| Peak | Nukey Bluff |
| Elevation | 465 m (1,526 ft) |
| Geography | |
| Country | Australia |
| State | South Australia |
| Region | Eyre Peninsula |
| Range coordinates | 32°32′S135°22′E/ 32.533°S 135.367°E |
| Geology | |
| Age of rock | Mesoproterozoic |
| Type of rock | Felsic Volcanics |
TheGawler Rangesare a range of stoney hills inSouth Australiato the north ofEyre Peninsula.TheEyre Highwayskirts the south of the ranges. TheGawler Ranges National Parkis in the ranges north ofKimbaandWudinna.The ranges are covered by the Gawler Ranges Native Title Claim.
History[edit]
Thetraditional ownersof the Gawler Ranges are theBarngarla,KokathaandWirangu peoples,who have inhabited the area for at least 30,000 years and are now known collectively as the Gawler Ranges Aboriginal People.[1]TheseAboriginal peoplesmaintained and usedrock holesin thegraniterock formations as a water source.[2]
The ranges were named byEdward John Eyreafter theGovernor of South Australia,George Gawlerin 1839.[3]This was on one of Eyre'searlier expeditionsbefore his famous crossing of theNullarbor Plainfurther west. It was on this expedition that Edward John Eyre made the first recorded sighting of South Australia's floral emblem, theSturt desert pea,in 1839 during an early exploration of the region.[4]
Stephen Hack explored the range in 1856 and in 1857 the firstpastoral leasewas taken up in the area,[5]Yardea,which was set up on the site of a former Aboriginal camp and included afreshwater springlater used as the station's water source. Moresheep stationswere soon established, includingHiltabaandPaney Station.[2]Two good seasons followed in 1857 and 1858, with pastoralists reporting permanent freshwater lakes on their runs. Stations were required to stock 50 sheep per square mile (19 per square kilometre) but soon properties such asNonningwere shearing flocks of 90,000.[5]
The first mail service from Port Augusta to Yardea commenced in 1876, with the telegraph service to Western Australia that passes through the range commencing in 1903[5]
Geology[edit]
The rocks within the ranges were formed by volcanic activity between ~1595-1592 Ma, when theGawler Range Volcanics(GRV) were erupted.[6]Approximately 30 000 km3of dominantlyrhyoliticanddaciticlavawere rapidly extruded, and their eroded remnants preserve one of the most voluminous felsic magmatic events preserved on earth.Basalticand basaltic-andesitecomprise a remarkably minor component of the magmatism (<1%). The Gawler Ranges Volcanics were also erupted at remarkably high temperatures (~950-1100 °C) for felsic magmas, and this, coupled with their very highhalogen(particularly F and Cl) compositions resulted in low viscosity (runny) magmas when compared to typical rhyolites and dacites which are generally several hundred degrees cooler. This lowviscosityresulted in emplacement as a series of lobate flows with a stacked pancake-like morphology which cooled rapidly resulting in porphyritic textures and widespreadcolumnar jointing.The ranges are a small part of theGawler Cratonwhich is acratonrich in mineral resources, although many are only recently discovered and not yet fully exploited.[citation needed]
There is muchpink granitein some areas, including on theHiltaba Nature Reserveon the western side of the ranges, which is located onHiltaba Suitegranite.[7]
At approximately 580Ma the Gawler Ranges were impacted by a largemeteoritewhich excavated theAcraman impact crater,in which the modern Lake Acraman now sits. The original crater was possibly as large as 90 km in diameter and flung fist-sized debris several hundred kilometres to the east, where it has been preserved in sediments which now comprise theFlinders Ranges.[citation needed]
Geomorphology[edit]
The highest point is Nukey Bluff at 465 metres (1,526 ft) above sea level. Bornhardtsdominate the landscape.[8]Soils are invariably dominated by the weathering products of the volcanics, and are typically red in colour due to abundant oxidised iron weathering in the arid environment. No major rivers drain the ranges, however several internal catchments feed the modern playa lakesGairdner,Acraman, Everard, McFarlane, Harry and Island Lagoon.
Flora and fauna[edit]
Birds[edit]
There are some 140 species of birds in the Gawler Ranges, including theemu,wedge-tailed eagle,Major Mitchell's cockatooandsinging honeyeater.[4]
Mammals[edit]
The Gawler Ranges are home to several larger mammals, like thesouthern hairy-nosed wombat[9]and the endangeredyellow-footed rock wallaby.[10]
Nature reserve[edit]
TheHiltaba Nature Reserve,owned byNature Foundation,abuts the Gawler Ranges National Park to the north, and works to protect manythreatened species.[1]
See also[edit]
Notes[edit]
- ^abDepartment for Environment & Water;National Parks & Wildlife Service South Australia(October 2017).Gawler Ranges National Park: Management Plan 2017(PDF).Government of South Australia.pp. 6, 13.Retrieved9 January2022.
Attribution 4.0 International (CC BY 4.0)licence.
- ^abKneebone, Sue;Jones, Philip G.;Knights, Mary (2010),Naturally Disturbed: 6 April - 7 May 2010(Exhibition catalogue, from an exhibition at the SASA Gallery.),University of South Australia
- ^"Gawler Ranges National Park"(PDF).Department for Environment and Heritage. Archived fromthe original(PDF)on 2008-07-31.Retrieved2009-11-12.
- ^ab"South Australia - Gawler Ranges".Archived fromthe originalon 2009-04-17.Retrieved2009-11-24.
- ^abc"History of the Gawler Ranges".Mt Ive Station. Archived fromthe originalon 17 March 2012.Retrieved15 March2015.
- ^Pankhurst et al., 2011A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
- ^Agangi, Andrea (2011).Magmatic and volcanic evolution of a silicic large igneous province (SLIP): the Gawler Range Volcanics and Hiltaba Suite, South Australia(PhD).University of Tasmania.Retrieved9 January2022.PDF
- ^Campbell, E.M.;C.R. Twidale(February 1991). "The evolution of bornhardts in silicic volcanic rocks in the Gawler Ranges".Australian Journal of Earth Sciences.38(1). Taylor & Francis: 79–83.Bibcode:1991AuJES..38...79C.doi:10.1080/08120099108727957.ISSN1440-0952.
- ^Deborah Furbank (2010): Briefing note on the Southern Hairy-nosed Wombat. Yorke Peninsula Natural Resource Management GroupPDFArchived2012-03-25 at theWayback Machine
- ^Informationsbroschüre des Parkverwaltung, engl., pdfArchived2011-03-14 at theWayback Machine
Further reading[edit]
- Andrewartha, H.G (1972).The Gawler Ranges. Report on a survey by the Nature Conservation Society of South Australia.NCSSA: Adelaide.
