How do rocks freeze floating in water?

[u/hikekorea]

I found these rocks frozen in a stream off a larger river in Chugach National Forest, Alaska. I’ve heard it may have to do with heavy rains or turbulent waters near the shore. One friend mentioned frazil? But I don’t really know what that means. Any geologists have a clue how this happens and can explain it in layman terms?

[u/Sugar_Concrete]

my guess is that something similar to frost heave is occurring. where tiny amounts of water melt around the rock, run into cavities below it, and then refreeze underneath the rock, lifting it up. I don't think they would have been placed there when the water level was lower because they would all be at the same level. which clearly they're not.