Was there any oil or soap content to the water? Or, perhaps, a residue
on the tarp before it collected water?
YGelmanPhoto wrote:
This may become too off-topic fro the forum, so please respond to me
personally at ygelmanphoto@xxxxxxxxx <mailto:ygelmanphoto@xxxxxxxxx>
and I'll try including interested discussants in my replies.
But I'll just put this out generally.
It was a good idea to look for reference articles -- I didn't even
begin to think about it that way. But the wikipedia article refers to
ice formed in moving water -- in which the circular shape is made by
ice in eddies rubbing against rock or other ice. Also, the size of
the discs in these articles are very large -- with photos of 10-25
foot disks and mention of one over 60 meters.
One very interesting article
<http://web.mit.edu/newsoffice/1993/river-0224.html> from MIT in 1993
described theories of ice di Charles River that year, but also very
large.
Here are some specifics of the disks in my photo:
1. The water was contained in a depression, or well, of plastic canvas;
2. Dimensions of the well were about 2 feet x 1.5 feet across and
about 3 inches deep at the center;
3. The well was located under a tree;
4. The disks formed overnight;
5. The largest disks were about 4 inches in diameter, opaque, with
slight roughness on the upper surface;
6. When first observed, the disks were surrounded by a layer of thin
ice that was nearly clear;
7. The clear ice contained many small opaque imperfections that may
also have been disks;
I can't believe that rotating water had anything to do with this.
There may have been something dropping into the well from the tree
branches, say small p drops.
Or, there may have been insects(?) in the water that somehow caused
initial crystallization that grew out from the center.
The trouble with crystallization growing out is that I've never heard
of circular crystallization.
That's all I can say for now.
-yoram
On Aug 14, 2010, at 10:05 AM, Palma Allen wrote:
Yoram Gelman - Ice Disks
I've never seen anything like that and I grew up by a river. Sorry, I cheated and looked it up.
http://en.wikipedia.org/wiki/Ice_circle
