Exploration and Mining Development

Photographic methods of seafloor mineral exploration were largely superseded in the 1970s by the use of underwater TV. This was supplemented by the use of precision depth recorders and other geophysical devices such as 3.5 kHz profiling and to a lesser extent magnetic and heat flow methods. Geochemical exploration was based on hydrothermal plume dispersion in the case of hydrothermal mineral deposits, and as thorough as possible an understanding of the relationship between manganese nodules and their environment of deposition in the case of manganese nodule exploration. Sampling tools developed from dredges through free fall grabs to large box corers during the period in question. Mining development in the 1960s and 1970s was principally focused on the development of deep-sea manganese nodule mining systems, several of which were tested successfully at sea in the 1970s. The development of a mining system for hydrothermal minerals was focussed on recovering metalliferous brines and sediments in the Red Sea and was also tested successfully.