To Vaughn, would you mind posting some of those www sites. I've
done a couple of searches for diamonds and diamond mining. Found
some useful sites but a lot were pretty elementary and repetitive.
To George, Walt and Vaughn, i, for one, appreciate it when we
get some technical discussion. Just the knowledge about the
various glacial periods and their effects was worth hearing.
I'd been wondering why I hadn't been able to find a map showing
the glacial ice flow for the area. if there were repeated ice
flows from variouis directions, then obviously there's a problem.
I'd appreciate a respnse to the following: if the shape of the
rocks, rounded or angular is insignificant in determining closenss
to a host source, then how significant is size? I would have
assumed that the further from the source, the more abraded the
rocks and therefore, the smaller they would be. However, not
being a glaciologist, I had nothing to go on except the model
of rocks moving downstream where the action of the water and the
stream bed would gradually reduce the rock size.
Something I raised over a year ago was the matter of local effect.
Living for a long time in Manitoba, I'm very aware of the action
of frost during the spring and fall. Farmers will clear the fields
of rock, but freezing and thawing seems to bring rock to the surface.
Is that possible? If so, then a "train" could be broken pieces of kimberlite from a dyke system.
Also, I'm aware from observation that lakes freezing have an expanding
surface. Last year, for example, ice piled two stories high in some
places along the shore of Lake Winnipeg. Ice reached the bottom of
the lake some distance out and brought with it a great deal of
bottom rock. This was deposited as the ice froze. In such a case
one can guarantee the closeness of the source. Could this boulder
train in question have been created by local ice when Snap Lake was
bigger but not necessarily a lot older? |
