1 There are other examples, I was wishing I had another one to show 



2 you, actually, which was simpler and more consistent, but where we do 



3 have some connection between the activities, particularly on the 



4 continental shelf and the fluxes and the texture of the material 



5 collected. 



6 I'd like to show you that the opportunity for scavenging occurs 



7 over a fairly thick section of the water column in the axis of Lydonia 



8 Canyon. This line, I think, illustrates that fact. These are x 



9 radiographs of the sediment traps, which are, in a sense, a core sample. 



10 They're in a tube, let's put it that way. 



11 A tube sample containing the trap material, when x rayed, give a 



12 wide variation in exposure or in texture throughout its length. We 



13 think we could correlate pretty well the sample that was located 20 



14 meters above the bottom, with samples higher in the water column at 56 



15 and at 102 meters. 



16 So, I think that when there's an event that causes resuspension in 



17 the canyon axis at LCB, which is just under 300 meters water depth, this 



18 kind of data suggests that the large part of the water column is 



19 influenced. 



20 My argument is there is a fair amount of scavenging that could 



21 take place, providing these particles are active with respect to 



22 absorption of whatever contaminant is available in the water column at 



23 the time. 



24 Well, we make the point here that there's lot of resuspension, but 



25 there's also some arguments that the sediment are accumulating in 



26 Lydonia Canyon and I'd like to summarize some of the evidence 



27 chronologically that lends some credence to that hypothesis. 



28 I think the first data comes from a map generated by David 



29 Twitchell, who used a combination of high-resolution seismic reflection 



30 and sidescan sonar to identify sediment fill, which he called recent 



31 sediment fill on the basis of their morphology and their orientation in 



32 the canyon axis. 



33 Some of these sedimentary deposits are up to 25 meters thick, and 



34 they are thought to be deposited beginning when sea level first started 



64 



