Apologies if seen and observed before!
Basically under each relic tower there is a clock which does not become active until after the tower is activated!
The clock has three tick marks and zooming in they look to have a deliberate structure so I don't think it's a glitch.
I think the other sites need checking for similar -which I will do when I next visit them...
Here is a close up of the clock "arm" whizzing past one of the ticks;
And a video so you can see it start up and then carry on turning;
https://www.youtube.com/watch?v=UBANd-V-6JQ
No idea what it should mean but the count of ticks may be significant and the number three does keep coming up.