Abstract The Australian continent has one of the best-preserved impact-cratering records on Earth, closely rivalling that of North America and parts of northern Europe, and the rate of new discoveries remains high. In this review 26 impact sites are described, including five small meteorite craters or crater fields associated with actual meteorite fragments (Boxhole, Dalgaranga, Henbury, Veevers, Wolfe Creek) and 21 variably eroded or buried impact structures (Acraman, Amelia Creek, Connolly Basin, Foelsche, Glikson, Goat Paddock, Gosses Bluff, Goyder, Kelly West, Lawn Hill, Liverpool, Matt Wilson, Mt Toondina, Piccaninny, Shoemaker, Spider, Strangways, Tookoonooka, Woodleigh, Yallalie, Yarrabubba). In addition a number of possible impact structures have been proposed and a short list of 22 is detailed herein. The Australian cratering record is anomalously biased towards old structures, and includes the Earth's best record of Proterozoic impact sites. This is likely to be a direct result of aspects of the continent's unique geological evolution. The Australian impact record also includes distal ejecta in the form of two tektite strewn fields (Australasian strewn field, 'high-soda' tektites), a single report of 12.1 – 4.6 Ma microtektites, ejecta from the ca 580 Ma Acraman impact structure, and a number of Archaean to Early Palaeoproterozoic impact spherule layers. Possible impact related layers near the Eocene – Oligocene and the Permian – Triassic boundaries have been described in the literature, but remain unconfirmed. The global K – T boundary impact horizon has not been recognised onshore in Australia but is present in nearby deep-sea cores. Keywords: Australiaimpact craterimpact ejectaimpact structuretektite Acknowledgments Reviews by Michael Dence and George Williams and editorial comments by Andrew Glikson improved the manuscript and are gratefully acknowledged. This paper is published with the permission of the Director, Geological Survey of Western Australia.
Allen, H.-J., Grey, K. & Haines, P.W., November 2015. Systematic description of Cryogenian Aralka Formation stromatolites, Amadeus Basin, Australia. Alcheringa 40, xxx–xxx. ISSN 0311-5518Recognition of stratigraphically constrained stromatolite assemblages has been useful in Australia-wide correlations of Neoproterozoic successions, and in particular in recent Geological Survey of Western Australia and Northern Territory Geological Survey revisions to Neoproterozoic–Cambrian stratigraphy and correlations in the Amadeus Basin, Australia. The Aralka Formation, a proven hydrocarbon source in the Northern Territory, previously mapped in only the northeastern part of the Amadeus Basin, is now recognized across much of the basin. The discovery of new outcrop and drillhole intersections with stromatolite occurrences has prompted systematic revision of stromatolites in the Aralka Formation and analysis of their distribution. The stromatolites include a new Group and Form, Atilanya fennensis, which has a distinctive pillared microstructure giving rise to a characteristic wrinkled lamina pattern of bioherms. The previously defined Tungussia inna is emended to include observations from new localities; robust bridging, columns that rarely develop for more than a few centimetres without interruption as a result of bridges being so profuse, and a wall that ranges from continuous to patchy. In situ occurrences of Tungussia inna are now known from ten localities in the Amadeus Basin, stratigraphically constrained within the Aralka Formation. Likewise, in situ Atilanya fennensis is, thus far, unique to the Aralka Formation, although similar forms elsewhere in the Centralian Superbasin and Adelaide Rift Complex are yet to be investigated.Heidi-Jane Allen [heidi.allen@dmp.wa.gov.au], Kathleen Grey [kath.grey@dmp.wa.gov.au] and Peter Wyatt Haines [peter.haines@dmp.wa.gov.au], Geological Survey of Western Australia, 100 Plain Street, East Perth WA, 6004.
Research Article| October 01, 2001 Pleistocene glass in the Australian desert: The case for an impact origin Peter W. Haines; Peter W. Haines 1School of Earth Sciences, University of Tasmania, GPO Box 252-97, Hobart, Tasmania 7001, Australia Search for other works by this author on: GSW Google Scholar Richard J.F. Jenkins; Richard J.F. Jenkins 2Department of Geology and Geophysics, University of Adelaide, North Terrace, Adelaide, South Australia 5005, Australia Search for other works by this author on: GSW Google Scholar Simon P. Kelley Simon P. Kelley 3Department of Earth Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, UK Search for other works by this author on: GSW Google Scholar Author and Article Information Peter W. Haines 1School of Earth Sciences, University of Tasmania, GPO Box 252-97, Hobart, Tasmania 7001, Australia Richard J.F. Jenkins 2Department of Geology and Geophysics, University of Adelaide, North Terrace, Adelaide, South Australia 5005, Australia Simon P. Kelley 3Department of Earth Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, UK Publisher: Geological Society of America Received: 21 Feb 2001 Revision Received: 10 May 2001 Accepted: 24 May 2001 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2001) 29 (10): 899–902. https://doi.org/10.1130/0091-7613(2001)029<0899:PGITAD>2.0.CO;2 Article history Received: 21 Feb 2001 Revision Received: 10 May 2001 Accepted: 24 May 2001 First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Peter W. Haines, Richard J.F. Jenkins, Simon P. Kelley; Pleistocene glass in the Australian desert: The case for an impact origin. Geology 2001;; 29 (10): 899–902. doi: https://doi.org/10.1130/0091-7613(2001)029<0899:PGITAD>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Irregular masses and flat slabs of vesicular, slaglike, and glassy melt (referred to herein as Edeowie glass) are locally abundant on a desert plain in central South Australia, where the material appears to be associated with an old land surface being exhumed by deflation and water erosion. The slabs of melt are associated with outcrops of baked sediment having very similar geochemistry, suggesting an origin by in situ surface fusion. Embedded clasts displaying shock metamorphism in quartz suggest that the thermal source may have been in some way associated with an impact event, although an obvious crater is lacking. If Edeowie glass is related to impact, a different thermal mechanism from that generally ascribed to the production of impact melt is required because of evidence for in situ generation of melt distal from any crater. 40Ar/39Ar laser probe dating of two samples has produced overlapping dates of 0.67 ± 0.07 and 0.78 ± 0.33 Ma. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Gravity data in the Canning Basin exhibit a northeast-trending linear feature that offsets a gravity ridge in the vicinity of the Jurgurra–Mowla Terraces with a displacement of about 30 km. The sharp displacement is aligned with similar disruptions on the Lennard Shelf to the northeast and Broome Platform to the southwest. The northeast part of the lineament also shows an anomalous offset on aeromagnetic images. However, the lineament does not correspond to fault displacement within the sedimentary succession of the Canning Basin based on seismic profiles. The geophysical responses to the linear feature vary in different areas, possibly caused by the different thickness of overlying sedimentary rocks across the basin. The lineament is interpreted as a left-lateral strike-slip fault that pre-dates the Canning Basin to account for the lack of seismic responses in the sedimentary section. This northeast-trending fault lies in the basement and might have originated during one of the younger Proterozoic to earliest Paleozoic orogenies pre-dating the Canning Basin. The northeast-oriented fault in the basement was orthogonal to the strike of the basin, thus was less likely to have significant impact on the basin deposition compared to the northwest-oriented faults, such as the Pinnacle and Fenton Fault system. However, these perpendicular features probably created a deeply seated crustal weakness near the intersection where the cluster of lamproite pipes of the Ellendale field intruded during the Miocene.
The Shoemaker Memorial Issue on the Australian impact record: 1997 – 2005 update reports on new discoveries and ongoing studies of Australian impact structures and impact-ejecta fallout deposits si...
The world-class Middle-Upper Devonian carbonate outcrops of the Lennard Shelf, Canning Basin, Western Australia, allow for examination of long-term reefal carbonate shelf-to-basin systems within a variety of settings and contexts, including hierarchical accommodation trends, global biological crises, greenhouse-to-transitional climatic changes and syn-depositional tectonics. This complex Devonian record contained within the Lennard Shelf outcrop belt has spurred, and will continue to promote, research that advances the broader understanding of carbonate systems, highlights of which include: 1) sequence development across a long-term backstepping-to-progradational platform evolution; 2) ecological, depositional and geochemical expressions related global biotic crises; 3) platform-to-basin facies distributions and stratal architecture related to an interplay of carbonate controls; and 4) the characterisation and prediction of early-formed fracture networks in a variety of settings. The relationships between fine-scale, shelf-to-basin carbonate heterogeneity and seismic-scale stratigraphic architectures demonstrated in these well-preserved exposures also allows for the development of predictive conceptual models of relevance to carbonate hydrocarbon reservoirs in the age-equivalent Canadian Alberta Basin and younger Carboniferous reservoirs of the Pricaspian Basin in Kazakhstan.
The Shoemaker impact structure, on the southern margin of the Palaeoproterozoic Earaheedy Basin, with an outer diameter of ∼30 km, consists of two well‐defined concentric ring structures surrounding a granitoid basement uplift. The concentric structures, including a ring syncline and a ring anticline, formed in sedimentary rocks of the Earaheedy Group. In addition, aeromagnetic and geological field observations suggest that Shoemaker is a deeply eroded structure. The central 12 km‐diameter uplift consists of fractured Archaean basement granitoids of syenitic composition (Teague Granite). Shock‐metamorphic features include shatter cones in sedimentary rocks and planar deformation features in quartz crystals of the Teague Granite. Universal‐stage analysis of 51 sets of planar deformation features in 18 quartz grains indicate dominance of sets parallel to ω {101 – 3}, but absence of sets parallel to π {101 – 2}, implying peak shock pressures in the range of 10–20 GPa for the analysed sample. Geophysical characteristics of the structure include a −100 µs −2 gravity anomaly coincident with the central uplift and positive circular trends in both magnetic and gravity correlating with the inner ring syncline and outer ring anticline. The Teague Granite is dominated by albite–quartz–K‐feldspar with subordinate amounts of alkali pyroxene. The alkali‐rich syenitic composition suggests it could either represent a member of the Late Archaean plutonic suite or the product of alkali metasomatism related to impact‐generated hydrothermal activity. In places, the Teague Granite exhibits partial to pervasive silicification and contains hydrothermal minerals, including amphibole, garnet, sericite and prehnite. Recent isotopic age studies of the Teague Granite suggest an older age limit of ca 1300 Ma (Ar–Ar on K‐feldspar) and a younger age limit of ca 568 Ma (K–Ar on illite–smectite). The significance of the K–Ar age of 568 Ma is not clear, and it might represent either hydrothermal activity triggered by impact‐related energy or a possible resetting by tectonothermal events in the region.
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