G50 



DATA OF GEOCHEMISTRY 



was also among the elements studied by Kleinkopf 

 (1955, 1960), who found amounts as high as 8 ppb in 

 440 lake waters from Maine. The mean was 0.177, 

 somewhat lower than that of Braidech and Emery. 

 Five hundred and thirty-six waters of California 

 (Calif. Dept. Water Eesources, 1957) contained as 

 much as 20 ppb with a mean of 0.3. Thirty-four 

 samples from major rivers of North America contained 

 as much as 84 ppb chromium with the rather high 

 mean of 10.8 ppb (W. H. Durum, written communica- 

 tion, 1960). With this much information one can 

 only say that the mean chromium content of ordinary 

 lake and river waters probably lies between 0.1 and 10 

 ppb, but may be a little higher. 



MOLYBDENUM 



The first measurements of the molybdenum content 

 of lake or river waters appear to be those of Kleinkopf 

 (1955, 1960), who found figures of as much as 2.50 ppb 

 in 419 lake waters from Maine. The mean of his 

 analyses was 0.023 ppb. Geidorov and Efendiev (1958) 

 found a mean content of 6.7 ppb in river waters of the 

 Istisu and Bagyrasakh areas, Azerbaidzhan, which are 

 rich in the element. Braidech and Emery (1935) 

 found traces of molybdenum in some of their waters, 

 but Novokhatskii and Kalinin (1939) were not able to 

 detect its presence in the salt lakes of Kazakhstan. In 

 a recent survey of major rivers of North America 

 figures up to 6.9 ppb were found. The mean for 29 

 samples was 0.84 ppm, but in more than half of these it 

 was not possible to demonstrate the existence of the 

 element (W. H. Durum, written communication, 1960). 



MANGANESE 



Very little is known about the state of manganese in 

 lake and river waters. Hutchinson (1957), in his 

 account of the limnological behavior of the element, 

 was forced to reason by analogy with its known be- 

 havior in soils, taking into account redox conditions 

 prevailing in lakes. 



Kleinkopf (1955, 1960), found a range from 0.02 to 

 87.5 ppb of manganese in 440 lake waters from Maine. 

 The mean was 3.8 ppb. After a few investigations of 

 variations with depth which did not yield positive 

 results, he investigated only surface waters, but other 

 workers have demonstrated very pronounced changes 

 in manganese concentration with depths in stratified 

 lakes. The most common situation appears to be one 

 in which the manganese content is high in the reduced 

 bottom water; it reaches high concentrations at a 

 somewhat shallower depth than iron, presumably be- 

 cause manganous ion is released from the bottom at a 

 slightly higher redox potential than ferrous iron 

 (Hutchinson, 1957, p. 809). A less common situation 

 occurs in some lakes, notably Ranu Klindungan in 



Java, which has a very pronounced peak in the manga- 

 nese curve just below the therm ocline with lower 

 concentrations in the deep hypolhnnion and a much 

 lower content in the surface water. Ruttner (1930) 

 believed that a manganiferous spring was involved in 

 the case of Ranu Klindungan, but in other lakes, such 

 as Schleinsee, Germany, a similar though less pro- 

 nounced manganese curve appears to be generated by 

 the accumulation of manganese in the unmixed layers 

 just below the level where oxygen is present in amounts 

 sufficient to precipitate manganous ion from solution 

 ^Hutchinson, 1957, p. 810). 



Ohle (1934) studying lakes in North Germany found 

 a total manganese content between less than 5 and as 

 much as 200 ppb. The mean was 25 ppb. One lake, 

 Trammersee, had a variation in manganese throughout 

 a single year that covered almost the entire range, 

 from less than 5 ppb to 133 ppb. Juday, Birge, and 

 Meloche (1938) found comparable amounts, 3 to 23 ppb 

 in the surface waters of 8 Wisconsin lakes. The deep 

 water of one lake contained 1200 ppb. Uniformly high 

 manganese contents have been recorded for some 

 waters — for example, 50 to 250 (mean of 140 ppb) for 

 Linsley Pond (Hutchinson, 1957, p. 803-804) and 80 

 to 120 ppb for the Mississippi River at Fairport, Iowa 

 (Wiebe, 1930). The mean for the rivers of the U.S.S.R. 

 is 11.9 ppb (Konovalov, 1959), but the global average 

 is probably somewhat higher. 



Lohammar (1938) has provided a very substantial 

 body of information on the manganese content of 

 waters of Sweden. There seems to be a slight difference 

 in the waters of northern and southern Sweden in this 

 respect. In north Sweden the range was > 10—460 

 ppb, with a mean of 33 ppb, and in south Sweden 

 >10-S50 ppb, with a mean of 44 ppb. Waters from 

 northern Sweden have a much higher iron content than 

 those from southern Sweden, and there seems very 

 little doubt that the Fe/Mn ratio is significantly 

 higher for the northern (30) than for the southern (5) 

 waters. 



Additional data for manganese may be found in 



papers by Yoshimura (1931a, b), Ruttner (1937), 



Einsele (1937, 1940), Yatsula (1959), and Harvey 



(1949) as well as in tables 9, 12, 13, 25-27, 29, 35, 47, 



50, 54, 66, 68, 71, and 72 of the general section of this 



report. 



uranium: 



Because of its radioactivity uranium has been the 

 subject of a number of hydrochemical investigations. 

 Some of the results are summarized in table 91. The 

 variation in the uranium content of natural waters is 

 so great that it would be necessary to have information 

 from all the major river systems in order to draw up a 

 reliable mean figure. A number of important rivers 



