mystery rocks symbols

[4windows]

i am new to this, and i would appreciate it if you can help me with this symbols.

 

[old digger]

I would say natural. Erosion can sure play trick.

 

[tamrock]

Those plants don't look like anything I've seen here in the USA. Strange, but natural erosive features is my guess on how those marks came to be also. Looks like a limestone and maybe the result of chemical erosion because of the higher content of calcium in limestone just the moisture in the atmosphere can react in breaking the rock down into odd shapes.

 

[Joe-Dirt]

#4 is pretty intriguing

 

[A2coins]

Reach into the hole and see whats in it lol

 

[A2coins]

Welcome to tnet from MI Tommy