which began in 1924 and which has dramatically increased each year since 1940 
until the recent switch to unleaded gasoline. Atmospheric transport of Pb 
with the prevailing westerly winds would move Pb to surface waters in this 
general location. A similar profile of lead was observed in sediments from 
the Mud Patch collected before drilling began (Bothner and others, 1981). 
We also analyzed sediment profiles from locations west of the drilling 
activity where deposition of transported drilling mud was expected. Both Ba 
and Ba/Al at station Ml10-12-00-GX are slightly enriched in the surface 8 cm 
compared to the deeper section of the core (fig. 16C). This supports the 
conclusion that Ba has been transported to this station, as discussed earlier 
using the data presented in figure 9A, B. At locations 0C140-39 and 0C140-41 
to the east of transect III (fig. 1), the Ba concentrations in fine fraction 
samples of the upper 5 cm are not elevated above the deeper sections in the 
sediments, but there is a slight enhancement in the Ba/Al ratio in the surface 
sediment (fig. 16A, B) that is statistically significant at the 99.9 percent 
level of confidence (t test). At stations M12-19 and M12-21, there are small 
increases in the Ba/Al ratio in the surficial sediment, but no increase in the 
Ba concentration (fig. 16D, F). Profile Ml12-20 shows no increase in either Ba 
or Ba/Al (fig. 16£E). At stations 19, 20, and 21, an increase in both Ba and 
Ba/Al in the surface sediments was measured at the time of cruise 9 (reported 
in Bothner and others, 1983). 
The Ba and Ba/Al profiles at stations Ml2-05 and M12-16, adjacent to 
drilling locations in blocks 312 and 410, respectively, show much higher 
concentrations than at any of the other more distant stations (fig. 17A, B). 
These profiles illustrate two points. First, fine-grained Ba-rich particles 
have penetrated to at least 15 cm depth since the drilling began at these 
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