This is a phenomenon I have been noticing for a while and I have never found a good explanation.
When a body of water has a certain amount and size of waves and the light is at the right angle the surface will look something like in pic related.
There are shapes of areas which are brighter and darker due. This is almost certainly because the surface in the brighter areas is more wavy and causes more dispersion,
This all seems quite obvious, some areas have more waves, but the strange thing is that these shapes are rather *persistent in time*
You can expect one of these areas where the water supposedly has more chaotic waves to keep its area for a minutes at a time! This is strange since the chaotic behaviour of water should imply that the shapes change all the time.
The problem is that I haven't caught a video of this yet. If the patterns you see in pic related looked completely different after a few seconds nothing interesting would be going on, but they do stay the same for extended periods of time!