wonder what those weird hologram symbols on the ground are for?

[ItsMaam]

use your ping near one and youll hear a sound. Follow it for you to find the vaults for the precise little minigames

[crashdodgers]

They are indicators to tell you that there is a vault close by.

[Djozar]

They let you know when you're near one of the statues that you use your scanner (Tab) on. Find one of those holograms. Hit "Tab" or press the right stick of the controller to activate your scan. Kind of like Destiny 2 when you search for the chests. You'll hear a "thud" sound if you are facing the correct direction. Walk in the direction of the "thud" and keep scanning as you go until you hear the thud change into a "ding". Now you look around in every crevice and hole.

Guides say the scan highlights the statues, but I have only found they mark the munition and resource boxes, while you search for the statues.