My friends here have heard me proclaim loudly that my “Algae-on-a-Stick” is the “best” fossil in my dad’s whole collection. The word “best”, of course, is just my opinion. But I have good reasons, To read more about it, see my blog essay at:
But I’m here today to proclaim a “Best of the Best” – I’m calling it “Petrified Swamp”.
To understand why I think this is such a great rock, we have to go back to my theory about what Algae-on-a-Stick is. I believe the rocks I have are clumps of moss or algae that have accumulated on something sticking up out of a swamp. Something happened, like the depth of the water increasing to submerge the clumps. After that, very fine sediment drifted through the water to gently bury them.
An unlikely sequence of events? Yes! That’s why I think they’re very unique fossils.
I got this idea from reading “Wonderful Life” by the paleontologist and evolutionary biologist Stephen Jay Gould. It’s all about the Burgess Shale fossils in the Canadian Rockies. These are fossils of soft bodied creatures that normally wouldn’t even leave a fossil because they’re just too fragile to be preserved. Gould’s idea is that something like being gently buried with fine sediment was what happened to these creatures to preserve them.
A friend asked to buy one of my Algae-on-a-Stick fossils and I was looking through the collection to find one for him when I found this rock. It was collected with the rest of the Algae-on-a-Stick fossils, but it’s clearly not the same. This is what I think it is.
The movement of wind and water can pile up leaves and sticks in a shoreline corner of a swamp. This pile can build up to depths of several inches. I think the very same thing that happened to clumps of moss and algae also happened to a pile of sticks like that and the whole pile was preserved.
In this rock, you can clearly see loose individual sticks piled on top and more compressed layers at the bottom. Fascinating.
Petrified Swamp!
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