peterSale

I got a book before Christmas. It was available at Collins Booksellers. I thought it might interest you.

It is called:-
The Geology of Australia by David Johnson.
Published by Cambridge University Press.

It is written for a general audience and is full of great pictures and diagrams.

Enjoy.

Also if you like geology watch this and tell me what you think of the descriptions.

http://www.nps.gov/yose/photosmultim...4-halfdome.htm

It does go for about 11 minutes though. It is about the half dome in Yosemite National Park

AlanJG

Thanks Peter, I have a signed first edition and if you look in the acknowledgments you'll find my name. David is one of those brilliant people who when asked a deceptively simple question can give a simple answer.

I often have to give the complicated answer first and can then summarise it.

I thought that I had convinced him about the formation of one of our local volcanoes but am now not sure after I heard him answer a question at a public meeting. Will tackle him when next we meet.

My speakers are not working on my computer at the moment so I'll look at it some other time.

peterSale

Well. Well. I was right then. You would enjoy it!

At least the thought was there.

Which volcano is under dispute?

Cheers.

AlanJG

Mt Quincan, just south of Yungaburra and the major story place of the Giant Devil Dingo story. It is an explosive cinder cone. Some have suggested that the winds from the south-east caused the apparent plume and ridge to the north west. At least one vulcanologist has suggested that there was another crater at the top of the hill and the existing one is a side shoot.

Both a clear nonsense if one walks over the area. Firstly the ridge has a few boulders bigger than my chest. While I am not big, no wind blew that there. Secondly the vent points to the top of the hill not away form it as in a side crater. The south-east side is lowest and steepest both inside and outside the crater.

Applying Occam's razor, the simple answer is that the vent is angled to the north-west. This accounts for the ridge in that direction and the saddle shape of the rim. Most of the ejected material went NW, less to the sides and least to the SW. It is much easier to show you in person than describe here.

David and I could find no evidence to counter my argument when we walked around the two small and one large quarries on the hill. Only the large quarry is still working, extracting the scoria for road and horticultural purposes. David is a sedimentologist so he was able to point out which layers were caused by slumping and which by aerial deposition.

David had actually given up geology when he retired but took it up again when what he was seeing on his property and on nearby blocks did not match with what he was reading from the geology maps of the area. He dedicated five years working at a high level to further the peace movement, ban land mines and having them removed from Indo-China. You may notice from my tone that I am a fan of his and not just because of his geological skills.

peterSale

Sounds a fascinating place and an even more fascinating man. (so do you)

Thanks.