An ancient grain of zircon found
In Jack Hill sandstone north of Perth,
Inside its crystal lattice bound:
Secrets of our planet’s birth.
The oldest grain (we rock hounds swoon),
Tells of magma oceans past,
An early impact yields the moon;
And all of this occurred so fast!
The zircon’s old, which then implies
That solid rocks must be still older.
In Canada, a sequence lies,
With implications even bolder!
A pattern locked within old lava
Echoes patterns from the deep;
Mariana-like subduction …
To plate tectonics, take the leap!
Hadean times are cloaked in intrigue,
Eons distant, full of strife,
Yet it seems these rocks held promise,
Full of boron, primed for life!
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In the news:
New Record for Oldest Earth Rock, Sky and Telescope
Hadean age for a post-magma-ocean zircon confirmed by atom-probe tomography, Nature Geoscience
The Dawn of Plate Tectonics, Science Now
Heading down early on? Start of subduction on Earth, Geology
