Abstract 



The analysis of Greenland ice suggests that the flux of mercury from the 

 continents to the atmosphere has increased in recent times, perhaps partly as a 

 result of the many of man's activities that effect an alteration of terrestrial 

 surfaces. Upon the exposure of fresh crustal matter, the natural outgassing of 

 mercury vapor from the earth's surface could be enhanced. 



Accordingly, mercury was measured in a variety of environmental materials 

 gathered from the North Slope of Alaska to provide background data prior to 

 the anticipated increase of activity in this environment. The materials were 

 collected during the U.S. Coast Guard WEBSEC 72-73 cruises as well as 

 through the facilities provided by Naval Arctic Research Laboratory in the 

 spring of 1973. 



The method of measurement depended upon radioactivation of mercury with 

 neutrons and the subsequent quantification of characteristic gamma radiations 

 after radio-chemical purification. 



Mercury concentrations in seawater at several locations in the vicinity of 

 151°W, 71°N averaged 20 parts per trillion. The waters from all stations east of 

 this location showed a significantly smaller concentration. This difference may 

 relate to penetration of Bering-Chukchi Sea water into the southern Beaufort 

 Sea to 151°W. Marine sediments on the shelf and slope between 143°W and 

 153°W contained about 100 parts per billion mercury, except for those on the 

 continental shelf between Barter Island and the Canning River, where the 

 concentration was less than half this value. These results are consistent with 

 sediment input from the respective rivers when their mercury content and 

 mineralogy are considered. The mercury content of river waters was 18 ppt and 

 in reasonable agreement with the average of snow samples (13 ppt). The 

 burden of mercury in plankton was 37 ppb. 



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