1 DR. NEFF: Are there other tracers for organic flux in the 



2 sediments, especially protective of organic matter, because that is a 



3 major mechanism for stripping solubles out of the water, absorption onto 



4 organic particles. Usually these are organic coatings on clays or some 



5 things like that. I wonder if there are any tracers for that. 



6 Are they mainly associated with the iron and manganese oxides or 



7 what phase is the lead associated with, the lead-210? 



8 DR. BOTHNER: From the evidence that Roy Carpenter has generated 



9 from the canyons on the west coast, the iron manganese oxides are, in 



10 fact, the most probable surface that is responsible for bonding the 



11 lead-210 into the sediments. 



12 DR. NEFF: That's true for the cold lead. I wasn't sure for the 



13 hot lead. 



14 DR. BOTHNER: It's true for the hot lead, as you phrase it, yes. 



15 DR. NEFF: It's chemically the same stuff. 



16 DR. BOTHNER: I know, I know, but we are using these model metals. 



17 DR. AYERS: Do we have any other data for--I mean I can see why 



18 you are saying that, but do you feel like--is there other data to 



19 support that maybe it's just--do we have enough to where you feel real 



20 comfortable with that, or do you feel like--rm sure you would like to 



21 have more data, but how much of that other data exists? 



22 DR. BOTHNER: I'm not aware of a lot of data. Well, let's see, 



23 the west coast information using lead-210 in the canyons versus slope 



24 confirms very much what we find here on the east coast. 



25 DR. AYERS: Okay. 



26 DR. BOTHNER: Actually, since their data was first, I think I 



27 confirmed them, versus the other way around. 



28 DR. BUTMAN: On the northern canyons of the west coast, there are 



29 sort of fine-grained canyons, not the canyons off southern California? 



30 DR. BOTHNER: Actually, the data does deal with the canyons off 



31 Washington and Oregon and they are even different from the ones off 



32 Lydonia in that they do not have tremendous resuspension at the bottom. 



33 There, the accumulation is thought to come from a mid-water layer 



34 which kinds of drapes off the continental shelf. Again, there are 



213 



