The interpretation of data collected at station 16 is somewhat 
complicated because the net concentration of Ba in the sample collected during 
cruise 4 was lower than that collected on cruise 10. The high spatial 
variability of Ba in sediment adjacent to the drilling rigs has already been 
discussed. The inventory at station 16 for cruise 4 has a strong peak in the 
210-500 um modal size (fig. 13A), similar to the distribution at control 
station 2 (fig. 11A), and a small enrichment of Ba in the finer size fractions 
compared to the uncontaminated control station. At station 16 on cruise 10, 
we measured a higher total concentration of Ba, with higher concentrations 
distributed in the finer fraction of cruise 10 than of cruise 4 (fig. 13B). 
The distribution of the Ba inventory for station 16 on cruise 10 (fig. 13A) is 
similar to the distribution at station 5-2 on cruise 10 (fig. 12A). We are 
planning to analyze a third sample from each station collected on cruise 12 
and to resample a blend from cruise 4 station 16, if sufficient archived 
material remains. 
Among the other metals analyzed in the size-separated samples (Al, Cd, 
Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn), only Al and Pb concentrations (and V for 
cruise 10) in the fractions finer than 30 ym at the drill sites are higher 
than those at the control station (Bothner and others, 1983; and Appendix 
table 4C). Concentrations of the remaining metals are distributed similarly 
at the three stations. 
Trace-metal concentrations of sediment-trap samples 
The objective of the sediment-trap experiment was to measure the 
concentration of drilling mud components in suspended matter and to determine 
if drilling mud was transported to the head of Lydonia Canyon. Sediment traps 
were deployed at various heights above the zea floor in the vicinity of Block 
312 and in Lydonia Canyon (appendix table 1C). This experiment was part of a 
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