1 DR. NEFF: This is a related question. Do you have a feel for 



2 . what the solid phase to which the PAH's are absorbed is? In other 



3 words, what is the solid phase, is it organic or clay? 



4 DR. BOEHM: That's a tough one. I do believe it's on the fine 



5 particle. What the phase is that makes up the fine particles, I'm not 



6 sure. I would hazard a guess that within the fine fraction you do have 



7 clays and you do have soot and that there are different types of 



8 particles in that fraction and you could separate them, and they're 



9 probably different particles. 



10 The implication here is not that all the fine particles are the 



11 same, they probably are different particles. The PAH's are probably 



12 with the organic part. 



13 DR. NEFF: The silt and clay is covered with organic coating, so 



14 it could be organic. 



15 DR. BOEHM: Yes, there's probably a mixture of fine particle 

 15 sources here, if anyone's ever looked at that. 



17 DR. BOTHNER: Paul, I'd like to ask given the statement that you 



18 made that Georges Bank and the slope area is pretty much a mixing pot 



19 where you find the organics associated with the fine-grained material in 



20 proportion to the amount fine-grained material that is there, I'm 



21 wondering--! don't quite understand why you can say there's up-canyon 



22 transport to account for the lobes of organic-rich or the PAH and 



23 hydrocarbon-rich sediments at the head of the canyon. 



24 Why can't that just be from the continental shelf going off shore? 



25 DR. BOEHM: I can't say that definitely. Up-canyon transport has 



26 been documented. Without a topographic explanation for that catch 



27 basin, without some physical reason why the material ought to just drop 



28 out at the heads of the canyon, it remains a working hypothesis that 



29 there is material that is spilling over at the top of the canyon, and 



30 that there is some steady state. 



31 I certainly don't have any proof of that, but physically I don't 



32 know if you can explain that lobe of material physically by just direct 



33 deposition. 



34 DR. BOTHNER: It looks like a blowout to you. 



86 



