| MadSci Network: Physics |
The ice may not have been buckling, but it was certainly moving around due to additional freezing underneath and due to contraction as it continued to cool. Mechanical stresses in ice can be very large, and I think you were probably hearing the ice adjusting very slightly in position against other parts of the ice. In essence it WAS buckling, but not so much that you could actually see it doing so.
John Link, MadSci Physicist
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