1 I think in terms of predicting effects of drilling, additional 



2 hypotheses for why the species are the way they are in the canyons are 



3 probably needed. Again, we don't have--a lot of our discussion is based 



4 on measurements within the axis, especially the geochemical 



5 measurements. 



6 As I tried to point out in the very beginning, the walls are a 



7 large area of the canyon and we just don't have very many measurements 



8 of the geochemistry or accumulation rates or any direct measurements of 



9 accumulation rates or stripping along the walls. 



10 In fact, from our physical measurements, the bottom currents--! 



11 probably didn't say this in my talk. The currents are bottom- 



12 intensified in the canyon and are much weaker above the bottom and, by 



13 inference, also on the walls. 



14 This stripping may only be occurring, or this heavy resuspension 



15 may only be occurring or primarily may be occurring in the axis. Again, 



16 Page brought up this morning that we don't have many textural 



17 measurements deeper than 1,000 meters to try to look at the ultimate 



18 fate of where materials are going in the canyon. 



19 During the break, the rapporteur also suggested we might think of 



20 this kind of box model of the canyon that we have. These arrows sort of 



21 indicate exchange. We have the upper canyon, which we have been 



22 predominantly talking about; the lower canyon, which we haven't talked 



23 about very much and then the slope and rise. 



24 In terms of rates for sediment transport or exchange, we really 



25 want to try to quantify. We've talked this morning, saying that this 



26 arrow definitely goes from the shelf to the upper canyon. We haven't 



27 talked very much about--and these are really question marks--what is the 



28 flux of the material from the upper canyon to the lower canyon, from the 



29 lower canyon to the slope. 



30 Actually, I guess the mechanism we discussed in Baltimore Canyon 



31 is a hypothesis of transport from the upper canyon to the slope and 



32 rise, also, for the suspended matter transport out in the mid-water 



33 column. 



211 



