Well, I have to admit that these colours had me thinking for about 5 minutes.
My conclusion goes back to science lessons at school.
Do you remember rotating some square pieces of film over a plastic ruler and seeing similar colours caused by stress of the plastic ?
That film was a polarising film and what did I have on my lens today to reduce reflections... yes you have guessed it, a polarising filter .
As you can see the ice to the immediate left is quite clear with the earth visible beneath
Of course my logic may be flawed but I cannot think of any other explanation for these colours on thin sheets of ice which were created by cold weather & water on a flooded field.
Landscape and travel