https://en.wikipedia.org/wiki/Volcanoge ... re_deposit
basicly iv mined soo little so idk whats underocean (this is base of basicly a smoke spout we see vids of at bottom of ocean)
but this chould be almost like a node regenerating walls around a central point and if dig to deep into it cave in or burn damage
They occur within environments dominated by volcanic or volcanic derived (e.g., volcano-sedimentary) rocks, and the deposits are coeval and coincident with the formation of said volcanic rocks. As a class, they represent a significant source of the world's copper, zinc, lead, gold and silver ores, with cobalt, tin, barium, sulfur, selenium, manganese, cadmium, indium, bismuth, tellurium, gallium and germanium as co- or by-products.
a slow but infinite ore node mostly random and sometimes no ore only
chert https://en.wikipedia.org/wiki/Chert
andesite https://en.wikipedia.org/wiki/Andesite
or basalt
and stolen from fog of war underground idea
if enter fog then your near one (covers huge area so still hard to find)