Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 11 July 1986:
Vol. 233. no. 4760, pp. 200 - 203
DOI: 10.1126/science.233.4760.200
Prev | Table of Contents | Next

Articles

The Acraman Impact Structure: Source of Ejecta in Late Precambrian Shales, South Australia

GEORGE E. WILLIAMS 1

1 The Broken Hill Proprietary Co. Ltd., Minerals Exploration Department, PO Box 860, Norwood, South Australia 5067, Australia, and Department of Planetary Sciences, Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721.

A major probable impact structure occurs in middle Proterozoic dacitic volcanics in the Gawler Ranges, central South Australia. The structure has an inner depressed area about 30 kilometers in diameter that contains the Lake Acraman salina, an intermediate depression or ring about 90 kilometers in diameter, and a possible outer ring approximately 160 kilometers in diameter. Outcrops of dacite in Lake Acraman are intensely shattered and contain shatter cones and multiple sets of shock lamellac in quartz grains. The Acraman structure is the largest probable impact structure known in Australia and is the likely source of dacitic ejecta found in late Precambrian marine shales some 300 kilometers to the east.

Submitted on December 2, 1985
Accepted on April 8, 1986


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Correlating the Ediacaran of Australia.
K. Grey and C. R. Calver (2007)
Geological Society, London, Special Publications 286, 115-135
   Abstract »    Full Text »    PDF »
"Canons" revisited and reviewed: Lester King's views of landscape evolution considered 50 years later.
C.R. Twidale (2003)
Geological Society of America Bulletin 115, 1155-1172
   Abstract »    Full Text »    PDF »
The Acraman asteroid impact, South Australia: magnitude and implications for the late Vendian environment.
G. E. Williams, GeorgeE. Williams, and MalcolmW. Wallace (2003)
Journal of the Geological Society 160, 545-554
   Abstract »    Full Text »    PDF »
Neoproterozoic biotic diversification: Snowball Earth or aftermath of the Acraman impact?.
K. Grey, M. R. Walter, and C. R. Calver (2003)
Geology 31, 459-462
   Abstract »    Full Text »    PDF »
Some personal thoughts on stratigraphic precision in the twentieth century.
H. S. Torrens (2002)
Geological Society, London, Special Publications 192, 251-272
   Abstract »    PDF »
Extraterrestrial impacts on earth: the evidence and the consequences.
R. A. F. Grieve (1998)
Geological Society, London, Special Publications 140, 105-131
   Abstract »    PDF »
Climatic geomorphology: a critique.
C. R. Twidale, C.R. Twidale, and Y. Lageat (1994)
Progress in Physical Geography 18, 319-334
   Abstract »    PDF »
Impact Ejecta Horizon Within Late Precambrian Shales, Adelaide Geosyncline, South Australia.
V. A. Gostin, V. A. GOSTIN, P. W. HAINES, R. J. F. JENKINS, W. COMPSTON, and I. S. WILLIAMS (1986)
Science 233, 198-200
   Abstract »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)