This is a few-months' jump back in time now, a continuation in posts from the July 4 Desolation Wilderness trip. I had begun to write this note, and saved the draft, before I left for Europe in late July; but life has been whirling since then. I intend to get around to publish something about the trip, but for now some images are publicly shared, with captions, on my Picasa page, and that's it.
The split boulder below is just cool, plain and simple. I wonder whether the angle of these cracks would tell us something about the molecular structure of granite. They certainly tell us a few things about water. At least I think so -- I assume this boulder cracked as a result of freeze/thaw expansion/contraction of water in its fissures.
Then again, maybe it just fell from above and shattered in place. That would have been a sight to behold.
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| Interestingly broken boulder, Desolation Wilderness, 2012. |
Below is a shot of the reflection of some glacial polish on a slab of granite on the south shore of Middle Velma Lake. Imagine: a slab of ice atop this surface, thick enough to weigh down the sediment between the two, enough to grind it smooth as it slid, ever so slowly.
Growing up in Wisconsin, I was schooled about glaciation and its visible relics on the earth's surface today. We skied and hiked through them: drumlins, eskers, kettles, kames, and moraines are abundant there. But it wasn't until studying physical geography and geomorphology in Colorado that I learned of glacial polish. It's all deeply fascinating and awe-inspiring, especially once you set foot on a landscape where these relics exist.
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| Glacial polish on granite, Middle Velma Lake, Desolation Wilderness, 2012. |
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