No idea what i am suppose to be looking @.. will check back for updates to see how interesting this is? 72 feet down in the ocean? cave? maybe fungus? ice crystals?
If one of the Mars- rovers took this picture it might be something of interest. Otherwise it looks all natural to me. Silt or fungus, dead coral ... We need more info of wehere it was taken. 72 ft of water isn't a problem for scuba (I used to freedive deeper than that 20 years ago). Climbing down (and back up!) 72 ft into a cave might be more challenging though.
I was thinking that too but then i look @ that dirt there and it looks kinda dryish- maybe something like in a slot canyon or something.. no idea tho really..
i have a lot of pictures taken in different feet...and now I'm
in 82 something and its very amazing area i found i figure out on my own its a group of constellation of stars ....now still digging up to reach the tunnel and i believe so.....ill post more pictures and I'm open up to tell the area.... for information is not in sea water but in below the ground...
I'm calling it some sort of mineral deposit. Not treasure and not a symbol. Post this in the Geological Forums section and you might get better answers. It would also help if you included some sort of size reference when you do.