Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment
Isolated quartzose pebbles, clusters of quartz granules, orthogonal aggregates of poorly sorted quartzose coarse sand, and ovoid pellets (≤2 mm long) of quartz silt occur in hemipelagic marine mudstone of the mid-Ediacaran Bunyeroo Formation exposed in the Adelaide Geosyncline (Adelaide Rift Complex...
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Online Access: | http://hdl.handle.net/2440/62063 https://doi.org/10.1080/08120099.2010.509408 |
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ftunivadelaidedl:oai:digital.library.adelaide.edu.au:2440/62063 2023-05-15T18:18:08+02:00 Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment Gostin, V. McKirdy, D. Webster, L. Williams, G. 2010 http://hdl.handle.net/2440/62063 https://doi.org/10.1080/08120099.2010.509408 en eng Taylor & Francis Ltd. Australian Journal of Earth Sciences, 2010; 57(7):859-869 0812-0099 1440-0952 http://hdl.handle.net/2440/62063 doi:10.1080/08120099.2010.509408 Gostin, V. [0000-0001-5928-7403] McKirdy, D. [0000-0003-1668-434X] © 2010 Geological Society of Australia South Australia Adelaide Geosyncline Officer Basin Ediacaran ice rafting glaciation impacts evolution Journal article 2010 ftunivadelaidedl https://doi.org/10.1080/08120099.2010.509408 2023-02-05T19:27:43Z Isolated quartzose pebbles, clusters of quartz granules, orthogonal aggregates of poorly sorted quartzose coarse sand, and ovoid pellets (≤2 mm long) of quartz silt occur in hemipelagic marine mudstone of the mid-Ediacaran Bunyeroo Formation exposed in the Adelaide Geosyncline (Adelaide Rift Complex), and ovoid pellets of quartz silt in cores of the correlative marine Dey Dey Mudstone from deep drillholes in the Officer Basin, South Australia. This detritus is interpreted respectively as dropstones, dumps, and frozen aggregates dispersed by sea ice possibly of seasonal origin, and till pellets transported by glacial ice. The ice-rafted material in the Bunyeroo Formation only has been found <10 m stratigraphically below and above a horizon of dacitic ejecta related to the 90 km diameter Acraman impact structure in the Mesoproterozoic Gawler Range Volcanics 300 km to the west. Furthermore, till pellets have been identified 4.4 to 68 m below distal Acraman ejecta in the Dey Dey Mudstone >500 km northwest of the impact site. The Acraman impact took place at a low paleolatitude (∼12.5°) and would have adversely affected the global environment. The stratigraphic observations imply, however, that the impact occurred during, but did not trigger, a cold interval marked by sea ice and glacial ice, although the temporal relationship with Ediacaran glaciations elsewhere in Australia and on other continents is unclear. Release from the combined environmental stresses of a frigid, glacial climate near sea-level and a major impact in low latitudes may have been a factor influencing subsequent Ediacaran biotic evolution. V. A. Gostin, D. M. Mckirdy, L. J. Webster and G. E. Williams Article in Journal/Newspaper Sea ice The University of Adelaide: Digital Library Australian Journal of Earth Sciences 57 7 859 869 |
institution |
Open Polar |
collection |
The University of Adelaide: Digital Library |
op_collection_id |
ftunivadelaidedl |
language |
English |
topic |
South Australia Adelaide Geosyncline Officer Basin Ediacaran ice rafting glaciation impacts evolution |
spellingShingle |
South Australia Adelaide Geosyncline Officer Basin Ediacaran ice rafting glaciation impacts evolution Gostin, V. McKirdy, D. Webster, L. Williams, G. Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
topic_facet |
South Australia Adelaide Geosyncline Officer Basin Ediacaran ice rafting glaciation impacts evolution |
description |
Isolated quartzose pebbles, clusters of quartz granules, orthogonal aggregates of poorly sorted quartzose coarse sand, and ovoid pellets (≤2 mm long) of quartz silt occur in hemipelagic marine mudstone of the mid-Ediacaran Bunyeroo Formation exposed in the Adelaide Geosyncline (Adelaide Rift Complex), and ovoid pellets of quartz silt in cores of the correlative marine Dey Dey Mudstone from deep drillholes in the Officer Basin, South Australia. This detritus is interpreted respectively as dropstones, dumps, and frozen aggregates dispersed by sea ice possibly of seasonal origin, and till pellets transported by glacial ice. The ice-rafted material in the Bunyeroo Formation only has been found <10 m stratigraphically below and above a horizon of dacitic ejecta related to the 90 km diameter Acraman impact structure in the Mesoproterozoic Gawler Range Volcanics 300 km to the west. Furthermore, till pellets have been identified 4.4 to 68 m below distal Acraman ejecta in the Dey Dey Mudstone >500 km northwest of the impact site. The Acraman impact took place at a low paleolatitude (∼12.5°) and would have adversely affected the global environment. The stratigraphic observations imply, however, that the impact occurred during, but did not trigger, a cold interval marked by sea ice and glacial ice, although the temporal relationship with Ediacaran glaciations elsewhere in Australia and on other continents is unclear. Release from the combined environmental stresses of a frigid, glacial climate near sea-level and a major impact in low latitudes may have been a factor influencing subsequent Ediacaran biotic evolution. V. A. Gostin, D. M. Mckirdy, L. J. Webster and G. E. Williams |
format |
Article in Journal/Newspaper |
author |
Gostin, V. McKirdy, D. Webster, L. Williams, G. |
author_facet |
Gostin, V. McKirdy, D. Webster, L. Williams, G. |
author_sort |
Gostin, V. |
title |
Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
title_short |
Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
title_full |
Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
title_fullStr |
Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
title_full_unstemmed |
Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment |
title_sort |
ediacaran ice-rafting and coeval asteroid impact, south australia: insights into the terminal proterozoic environment |
publisher |
Taylor & Francis Ltd. |
publishDate |
2010 |
url |
http://hdl.handle.net/2440/62063 https://doi.org/10.1080/08120099.2010.509408 |
genre |
Sea ice |
genre_facet |
Sea ice |
op_relation |
Australian Journal of Earth Sciences, 2010; 57(7):859-869 0812-0099 1440-0952 http://hdl.handle.net/2440/62063 doi:10.1080/08120099.2010.509408 Gostin, V. [0000-0001-5928-7403] McKirdy, D. [0000-0003-1668-434X] |
op_rights |
© 2010 Geological Society of Australia |
op_doi |
https://doi.org/10.1080/08120099.2010.509408 |
container_title |
Australian Journal of Earth Sciences |
container_volume |
57 |
container_issue |
7 |
container_start_page |
859 |
op_container_end_page |
869 |
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1766194549199208448 |