[meteorite-list] It's a 'hole' lotta fun ("Cooradigbee crater")

[Paul H.]

In "It's a 'hole' lotta fun" at:
http://six.pairlist.net/pipermail/meteorite-list/2012-September/087340.html
Tom Randall wrote 

“Cooradigbee crater? Anyone have any more info on this?

http://bit.ly/NHLhWu “

The article is It's a 'hole' lotta fun” by Tim the 
Yowie Man, Travel Section, The Age at

http://www.theage.com.au/travel/blogs/yowie-man/its-a-hole-lotta-fun-20120921-26cnh.html

There is a picture of the alleged crater at:

http://images.theage.com.au/2012/09/21/3654727/art353-yowie3-300x0.jpg

Given the small size of it and the indefinite location
it is hard to tell much about from a literature review
and without going there. Judging from the lack of 
any well defined rim and any reported evidence other 
than tilted rocks, it does not look at all promising. Still, 
any definitive conclusion would have to come from 
an onsite inspection by a professional or avocational 
geologist.

The video does claim that rocks being “45 degrees to
the west” in one place and being “45 degrees to the 
east” in another part of the area as evidence of an 
impact. The Brindabella 1:100 000 Geological Map (Owen
and Wyborn 1979), Canberra 1:250,000 scale geologic 
map (Gilligan 1974), Goulburn 1:250 000 Geological Map 
(Johnson et al. 2010), and the Yass 1:100 000 Geological 
Map (Colquhoun 2008), demonstrate that the area of
Lake Burrinjuck, New South Wales within which the 
Cooradigbee Homestead (and “Cooradigbee Crater”) occurs
consist of tightly folded, faulted, and otherwise deformed 
Early Devonian volcanic, volcanoclastic, and terrigeneous 
sedimentary rocks. There is also a thick layer of folded and 
faulted “massive to thin-bedded fossiliferous limestone 
and calcareous shale” in the area of Wee Jasper. As a result, 
a person will need more than tilted strata to argue for the 
existence of a impact crater. Also, depending on the 
location of this shallow topographic bowl, a person might 
have to exclude the possibility it is a sinkhole.

For Google Earth fans, the location of the Cooradigbee 
Homestead is 35 degrees, 3’, 49.73”S, and 148 degrees,
39’, 37.61” E.

Reference cited

Colquhoun G. P., A. Y. E. Warren, R. G. Cameron, A. J. Johnston,
and D. J. Pogson, 2008, Yass 1:100 000 Geological Sheet 8628, 
2nd edition. Geological Survey of New South Wales, Sydney.
http://www.resources.nsw.gov.au/geological/geological-maps/1-100-000/yass-1100-000-geological-map
http://www.resources.nsw.gov.au/geological/geological-maps/1-100-000#central

Gilligan, L. B., 1974, Canberra 1:250,000 Metallogenic Map. 
Geological Survey of New South Wales, SI/55-16, Sydney, Australia. 
http://www.resources.nsw.gov.au/geological/mineral-maps-data/1-250-000/canberra-1250-000-metallogenic-map
http://www.resources.nsw.gov.au/geological/mineral-maps-data/1-250-000

Johnston, A. J., M. M. Scott, O. D. Thomas, D. J. Pogson, A. Y. E. 
Warren, L. Sherwin, G. P. Colquhoun, J .J. Watkins, R. G. Cameron, 
G. P. Macrae and R. A. Glen., 2010, Goulburn 1:250 000 
Geological Sheet SI/55-12, Provisional 2nd edition, Geological 
Survey of New South Wales, Maitland.
http://www.resources.nsw.gov.au/geological/geological-maps/1-250-001/goulburn-250k-geological-map
http://www.resources.nsw.gov.au/geological/geological-maps/1-250-001

Owen, M. and D. Wyborn, 1979, Brindabella (NSW and ACT) 
1:100 000 Geological Map First Edition, BMR, Canberra
http://www.resources.nsw.gov.au/geological/geological-maps/1-100-000/brindabella-1100-000-geological-map
http://www.resources.nsw.gov.au/geological/geological-maps/1-100-000#central

For other Australian geological maps go to:

Scanned 1:250 000 Geology Maps of Australia
http://tinyurl.com/GeologicalMapsAustralia
http://www.geoscience.gov.au/index.html

Best wishes,

Paul H.