12 
percent, manganese (Mn) 24.6 percent and cobalt (Co) 0.23 percent, 
while the nodules from the red clays contain Ni 0.76 percent, Cu 0.49 
percent, Mn 18.2 percent and Co 0.25 percent. 
TABLE 3.—AVERAGE ANALYSES OF MANGANESE NODULES 
[In percent of dry weight] 
Region Nickel Copper Manganese Cobalt 
North Pacific siliceous ooze_._.____-___.------_------- 1.28 1.16 24.6 0. 23 
NorthiRactficwrediclaya san sna ee eee . 16 -49 18.2 25 
South Pacific elevations_____________________________- -Al . 13 14.6 .18 
South Pacific abyssal plain.___._____________________- .51 . 23 15.1 . 34 
NorthsAtlanticns See Lae eae ete . 38 15 14.2 .34 
SouthgAtlanticSess eee? Sete a were es 48 .15 18.0 .3l 
lnidtantOcean setae ae sere me Ae es . 50 .19 14.7 . 28 
Source: United Nations. Economic significance, in terms of seabed mineral resources, of the various limits proposed for 
national jurisdiction. Committee on the peaceful uses of the seabed and the ocean floor beyond the limits of national juris- 
diction, A/AC.138/87, June 1973: 39 pages plus appendixes. 
SOUTH PACIFIC OCEAN 
In the South Pacific many manganese nodule deposits are concen- 
trated along the southern edge of the equatorial belt and on or close 
to submarine elevations such as the Manihiki Plateau, Tuamotu Archi- 
pelago, Cook Islands, and Society Islands (Fig. 4). Although not as 
extensive as those in the North Pacific, there are several mine grade 
nodule deposits in the South Pacific and some have high cobalt content 
up to 2.3 percent. Average metal values for the South Pacific are given 
in Table 3. 
NORTH ATLANTIC OCEAN 
In the North Atlantic nodules appear to be concentrated on the 
Blake Plateau (in water depths of about 1000 m) and in the red clay 
area 1800 km east of Florida (Fig. 5). Some encrustations occur on 
the Mid-Atlantic Ridge. In general, the nodules have low metal con- 
tent (Ni 0.18—0.32 percent, Cu 0.08-0.29 percent, Mn 13.9-14.5 percent, 
Co 0.35-0.42 percent) and some have high density or include sub- 
stantial quantities of carbonate material unfavorable for metallurgical 
processing. 
SOUTH ATLANTIC OCEAN 
Thick crusts and nodule deposits occur in some areas of the South 
Atlantic. However, the deposits are generally below commercial in- 
terest in metal content. One of the more extensive areas of manganese 
nodules and crusts in the South Atlantic is off the west coast and 
southward of South Africa (Fig. 6). The deposits in this area average 
0.67 percent nickel and 0.16 percent copper. 
INDIAN OCEAN 
Several areas of nodules and crusts are reported in the Indian Ocean, 
such as the Agulhas Plateau, the Madagascar Basin, and the Crozet 
Basin (Fig. 6). These deposits generally have metal contents below 
commercial interest though some potentially minable deposits are 
ae. by industry sources to have been discovered in the Indian 
cean.”? 
United Nations A/AC. 138/87, op. cit., p. 22. 
