fragmentary; in some—especially long-term habitation problems—it 
is essentially nonexistent. Current research activity, directly appli- 
cable to oceangoing operations, is minimal in most of these areas. 
Men working underwater require a wide range of support facilities. 
These include various underwater vehicles, underwater chambers in 
which to live and shore facilities for studying the effects of high pres- 
sure. Shore facilities should perhaps include high-pressure chambers 
for studies on man and animals, with capabilities to stmulate depths 
of at least 1,000 feet. 
Facilities are needed to meet the problem outlined above. In no 
university or private institution in the United States is there an ex- 
tensive investigative program on the effects of very high pressures 
on man. The Navy is carrying out studies of man’s long-term ex- 
posure to depths, but investigations are not primarily concerned with 
basic physiological effects at high pressure. Research of this type 
requires teams of trained specialists in medicine and biology and might 
best be conducted by a university medical center (see sec. 10.7). 
The Panel does not foresee the need for a diver-operating capability 
in depths beyond 1,000 feet before 1975. At greater depths the diver 
will be replaced with highly instrumented platforms capable of ma- 
neuvering sensing devices, communicating with the surface and per- 
forming useful work. The technology being developed for space 
application may contribute substantially to unmanned operations at 
depth. Very likely these platforms will be manned and will require 
containers at atmospheric pressure. 
4.12. MARINE MINING 
The possibility of mining the sea floor has caught the popular 
imagination because of numerous articles and speeches about the po- 
tential riches of the sea. Mineral resources certainly exist under the 
oceans, but their economic potential varies enormously, depending on 
depth, location, and geological setting. Accordingly, we distinguish 
three general classes of minerals: Surface deposits on the shallow con- 
tinental shelves; bulk deposits within the rocks under the shelves; 
and deposits on and in thin sediment layers of the deep sea floor (see 
also app. III.4). 
The surface ore deposits of the Continental Shelf are mainly of 
two types, placer ores concentrated in submerged river channels and 
beaches and blanketing layers of nodules such as phosphorite, precipi- 
tated from sea water. ‘These types of ores have been mined in various 
places around the world. Examples are: diamonds off Africa; tin off 
southeastern Asia; iron ores off Japan; and gold in many places. 
An attempt to mine phosphorite off California was apparently frus- 
trated by a concentration of unexploded naval shells. Various coun- 
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