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Reposting Pam's Odd Rock/Fossil - 2nd opinion?
Pam, I'm reposting your odd rock because it continued to trouble me and I had a radical idea that I am floating here for anyone to weigh in with their opinions. Here's the rock or fossil or whatever it is:
Now... I see shrinkage cracks towards the back, I see black glassy or crystalline material in the cracks so I'm thinking igneous, probably basaltic lava, probably pillow lava from rapid cooling as a result of molten rock meeting water. Igneous tells me it can't be a fossil so it has to be just an odd, weathered shape.
Or is it?
What occurred to me afterwards is that it is in fact possible to find fossils in igneous rocks (especially volcanic ones) if we stretch our definition of fossils just a bit. You may have seen these kinds of poignant casts of people who were buried in volcanic ash at Pompeii and Herculaneum from the eruption of Vesuvius in Roman times:
Dogs, too:
Even a loaf of bread, forever preserved in stone:
But these were special circumstances weren't they? And these organic objects were mostly preserved as casts in deep layers of compacted volcanic ash. Well, that's true, but take a look at these examples which resulted from molten lava meeting something organic:
What we have here is an assortment of seal pups and penguins that were swamped by a molten lava flow about 100 years ago on Barthalome Island in the Galapagos.
Events like this are unusual, but not actually rare. Here's some examples from Hawaii:
This is a Pandanas fruit cast in basaltic lava. It's a mere ten years old.
This is obviously a fish, also cast in basaltic lava and a mere fifteen years old.
Examples of this kind of formation are typically from recent eruptions but there are older examples too, like this (now empty) cast of a palm tree in basaltic lava which dates to around 2000 years ago.
So, these are "igneous fossils" of a kind. Given the odd shape of Pam's rock, I just wonder if it is the result of lava smothering something organic and taking on that shape? Not recently of course. Also not a trilobite I feel, but I wonder what? Old knobbly bit of wood or something of the kind? I know that most of Ohio's basalt is truly ancient (pre anything likely to be organic) from the "Middle Run Formation", but have there been any more recent intrusions of lava? Anyone know?
Watcha think?
Roger
Now... I see shrinkage cracks towards the back, I see black glassy or crystalline material in the cracks so I'm thinking igneous, probably basaltic lava, probably pillow lava from rapid cooling as a result of molten rock meeting water. Igneous tells me it can't be a fossil so it has to be just an odd, weathered shape.
Or is it?
What occurred to me afterwards is that it is in fact possible to find fossils in igneous rocks (especially volcanic ones) if we stretch our definition of fossils just a bit. You may have seen these kinds of poignant casts of people who were buried in volcanic ash at Pompeii and Herculaneum from the eruption of Vesuvius in Roman times:
Dogs, too:
Even a loaf of bread, forever preserved in stone:
But these were special circumstances weren't they? And these organic objects were mostly preserved as casts in deep layers of compacted volcanic ash. Well, that's true, but take a look at these examples which resulted from molten lava meeting something organic:
What we have here is an assortment of seal pups and penguins that were swamped by a molten lava flow about 100 years ago on Barthalome Island in the Galapagos.
Events like this are unusual, but not actually rare. Here's some examples from Hawaii:
This is a Pandanas fruit cast in basaltic lava. It's a mere ten years old.
This is obviously a fish, also cast in basaltic lava and a mere fifteen years old.
Examples of this kind of formation are typically from recent eruptions but there are older examples too, like this (now empty) cast of a palm tree in basaltic lava which dates to around 2000 years ago.
So, these are "igneous fossils" of a kind. Given the odd shape of Pam's rock, I just wonder if it is the result of lava smothering something organic and taking on that shape? Not recently of course. Also not a trilobite I feel, but I wonder what? Old knobbly bit of wood or something of the kind? I know that most of Ohio's basalt is truly ancient (pre anything likely to be organic) from the "Middle Run Formation", but have there been any more recent intrusions of lava? Anyone know?
Watcha think?
Roger
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