Thursday, May 01, 2008

More from Ottawa

Geophile, for Bruce from Ottawa

I walked another section of the Stony Swamp Conservation Area after work today.
For the most part, the reserve is a normal climax forest with the occasional stone poking above ground in a natural way. But the region has numerous natural escarpments and ancient shorelines, dating to the retreat of the ice 10-15 thousands of years ago and in some cases from long before that. Elsewhere in this same area is a marvelous display of 450-million-year-old beach ripples! The region has had a varied geological history.
Below these escarpments is the normal rockfall material: blocks that have broken off the rock faces and rolled a bit before stopping. No surprise there. But I'm noticing that on top of these little escarpments are frequently found small rock piles, a few feet back of the edge.
I'm seeing this consistently here. I don't see a natural causation for this. Neither do I see how these piles could be field clearances, as their positioning doesn't make sense as a field clearing pile, at least in my opinion.
Also, these piles are not places where soil erosion has revealed buried glacial stones - the stones are above-grade.
I started viewing the Rock Piles Blog a while back and didn't think it possible that the phenomenon came this far north. While I don't say the piles I'm seeing here are great examples, I do now believe the as-found landscape here has been "customized" for some purpose by past inhabitants of the land. (The proliferation of beer bottles on the ground indicates a new customization for somewhat less noble purposes!)
/bruce/ He also thanked everyone on the blog for their work in this area.
While I'm on here, if anyone knows anywhere near Springfield, Massachusetts where there are accessible rock piles or other stone features, I would be grateful if you would tell me. I'll be going there soon and I would love to see a site or two. Thanks!


pwax said...

I am getting more sensitive to the look of what I call a rock pile "smear" - which is the final stage of randomization of the rocks before they become buried or otherwise lose their integrity as recognizable man-made rock piles. These piles from Bruce look like "smears" in that sense. Placed as he describes them along an escarpment, it is easy to imagine these used to stand tall and be visible from below or from a distance. If so, then the piles and their locations would be a lot like the ones described for Little Mullberry Park in Georgia.

Also, about the extent of the rock pile "phenomenon", at a minimum we should assume it includes the territory associated with Algonquian speaking people. For examples outside of New England, the Yurok make stone piles in CA and I assume the Arapaho did as well in the Plains [though I cannot find anything in a quick Google search].

Finally, about sites near Springfield: searching for that word using the "SEARCH THIS BLOG" feature at the top of the page, I find Norman Muller reporting on some chambers he saw while visiting there. Worth asking him for his contact information. And also, don't forget to look me up if you get a bit further east.

pwax said...

Just thought of something to add. I have noticed that larger stacked rock piles use flat "plate" rocks lying over smaller ones, to add stability. You cannot just stack up small rocks but need these stabilizing larger plates.

So, even in a "smeared" rock pile, it is worth looking for these larger flat rocks mixed in with the smaller ones. That would be indirect evidence that the pile used to be stacked up higher. A hint anyway.

Norman said...

As for contacts around Springfield, e-mail me directly, as I have the name of a man who lives in the Springfield area, and he has shown me sites just to the west of the city.