Morphology and Internal Structure of Hydrothermal Orebodies Formed in Various Geological Settings of the World Ocean

Abstract

The variety of information obtained during scientific research and exploration of seafloor massive sulfide (SMS) deposits include significant data on the morphology of orebodies formed in various geological settings. On the example of hydrothermal vent fields in the Northern Mid-Atlantic Ridge, different hydrothermal ore structures are described, from the most common mound-shaped to rarely encountered “smoking craters.” The processes that govern the morphology of orebodies are analyzed, including alterations during the evolution of hydrothermal ore-forming systems. In contrast to the study of SMS deposits outcropping on the seafloor, the internal structure and formation models are mostly hypothetical. In particular, this concerns assumptions on the presence of massive sulfides and their formation mechanism below the paleo/subseafloor surface. Obviously, the results of drilling planned in the near future will make it possible to confirm or refute existing models and change the resource assessments, which are currently based on surface sampling of SMS deposits.