Gosses Bluff impact structure

{{Short description|Impact structure in Northern Territory}}

{{Use dmy dates|date=June 2020}}

{{Use Australian English|date=August 2019}}

{{Infobox terrestrial impact site

| name = Gosses Bluff impact structure

| other_name = Tnorala

| photo = Gosses Bluff Northern Territory Australia.jpg

| photo_size =

| photo_alt =

| photo_caption = View of Gosses Bluff impact structure

| map = Australia

| map_alt =

| map_caption = Location of the impact structure in Australia

| map_size =

| location = Namatjira{{cite web| title=Place Names Register Extract for "Gosses Bluff" |url=https://www.ntlis.nt.gov.au/placenames/view.jsp?id=22369 |website=NT Place Names Register |publisher=Northern Territory Government |access-date=10 May 2019}}

| label =

| label_position =

| coordinates = {{coord|23|49|15|S|132|18|28|E|region:AU-NT_type:landmark_scale:100000|display=inline,title}}

| coordinates_ref =

| confidence = Confirmed

| diameter = {{cvt|22|km}}

| depth =

| rise =

| imp_size =

| age = 142.5 ± 0.8 Ma
Early Cretaceous

| exposed = Yes

| drilled = Yes

| bolide =

| translation =

| language =

| pronunciation =

| topo =

| access =

| country = Australia

| state = Northern Territory

| province =

| district =

| municipality = MacDonnell Region

}}

Gosses Bluff (or Gosse's Bluff) is thought to be the eroded remnant of an impact crater.

{{cite Earth Impact DB|name=Tnorala/Gosses Bluff|linkname=gossesbluff|access-date=2018-04-08}}

{{cite journal |last=Milton |first=D. J. |display-authors=etal |year=1972 |title=Gosses Bluff Impact Structure, Australia |journal=Science |volume=175 |issue=4027 |pages=1199–1207 |bibcode=1972Sci...175.1199M |doi=10.1126/science.175.4027.1199 |pmid=17794191}}

{{cite journal |last1=Milton |first1=D. J. |last2=Glikson |first2=A. Y. |last3=Brett |first3=R. |year=1996 |title=Gosses Bluff—a latest Jurassic impact structure, central Australia. Part 1: geological structure, stratigraphy, and origin |journal=AGSO Journal of Australian Geology & Geophysics |volume=16 |issue=4 |pages=453–486 |hdl=10070/89299}} Known as Tnorala to the Western Arrernte people of the surrounding region, it is located in the southern Northern Territory, near the centre of Australia, about {{cvt|175|km}} west of Alice Springs and about {{cvt|212|km}} to the north-east of Uluru (Ayers Rock). It was named by Ernest Giles in 1872 after Australian explorer William Gosse's brother Henry, who was a member of William's expedition.

Formation

File:ISS007 Gosses Bluff.jpg]]

File:Gosse Bluff from Tylers Pass (cropped).jpg

The original crater is thought to have been formed by the impact of an asteroid or comet approximately 142.5 ± 0.8 million years ago,

{{cite journal |last1=Milton |first1=D. J. |last2=Sutter |first2=J. F. |year=1987 |title=Revised age for the Gosses Bluff impact structure, Northern Territory, Australia, based on Ar-40Ar-39 dating |journal=Meteoritics |volume=22 |issue=3 |pages=281–289 |bibcode=1987Metic..22..281M |doi=10.1111/j.1945-5100.1987.tb00625.x}} in the earliest Cretaceous, very close to the Jurassic–Cretaceous boundary. The original crater rim has been estimated at {{convert|22|km|abbr=on}} in diameter, but this has been eroded away. The {{convert|5|km|mi|-diameter|adj=mid|spell=in}}, {{convert|180|m|ft|-high|adj=mid}} crater-like feature,{{cite book |author=Parks and Wildlife Commission of the Northern Territory |url=http://nt.gov.au/nreta/parks/manage/plans/pdf/tnorala.pdf |title=Tnorala Conservation Reserve (Gosse's Bluff): Plan of Management |date=May 2007 |publisher=Northern Territory Government |isbn=978-1-920772-87-1 |access-date=2009-11-25 |orig-year=March 1997 |archive-url=https://web.archive.org/web/20091006171944/http://nt.gov.au/nreta/parks/manage/plans/pdf/tnorala.pdf |archive-date=2009-10-06 |url-status=dead}} now exposed, is interpreted as the eroded relic of the crater's central uplift. The impact origin of this topographic feature was first proposed in the 1960s, the strongest evidence coming from the abundance of shatter cones.

{{cite journal |last=Dietz |first=R. S. |year=1967 |title=Shatter Cone Orientation at Gosses Bluff Astrobleme |journal=Nature |volume=216 |issue=5120 |pages=1082–1084 |bibcode=1967Natur.216.1082D |doi=10.1038/2161082a0 |s2cid=4279783}} In the past the crater has been the target of petroleum exploration, and two abandoned exploration wells lie near its centre.

Cultural significance

The site is known as Tnorala to the Aboriginal people of the Western Arrernte language group, and is a sacred place. It is now located in the Tnorala Conservation Reserve.[https://nt.gov.au/leisure/parks-reserves/find-a-park-to-visit/tnorala-gosse-bluff-conservation-reserve NT Govt parks and reserves] A Western Arrernte story attributes its origins to a cosmic impact: in the Dreamtime, a group of celestial women were dancing as stars in the Milky Way. One of the women grew tired and placed her baby in a wooden basket, or turna (also known as a coolamon{{cite web |last=Salleh |first=Anna |date=20 September 2021 |title=Indigenous perspectives on country feature in Back to Nature documentary |url=https://www.abc.net.au/news/science/2021-09-21/indigenous-perspectives-on-country-back-to-nature/100365124 |access-date=21 September 2021 |website=ABC News}}). As the women continued dancing, the basket fell and plunged into the earth. The baby fell to the earth and forced the rocks upward, forming the circular mountain range. The baby's parents, the evening and morning star, continue to search for their baby to this day. The turna can be seen in the sky as the constellation Corona Australis.

{{cite journal |last1=Hamacher |first1=D. W. |last2=Norris |first2=R. P. |year=2009 |title=Australian Aboriginal Geomythology: Eyewitness Accounts of Cosmic Impacts? |journal=Archaeoastronomy |volume=22 |page=62 |arxiv=1009.4251 |bibcode=2009Arch...22...62H}}

{{cite journal |last1=Hamacher |first1=D. W. |last2=Goldsmith |first2=J. |year=2013 |title=Aboriginal Oral Traditions of Australian Impact Craters |journal=Journal of Astronomical History and Heritage |volume=16 |issue=3 |pages=107–126 |arxiv=1306.0278 |bibcode=2013JAHH...16..295H}}

See also

References

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