1 are sourced in the higher molecular weight PAH's which are of combustion 



2 origin. 



3 So, the compositions of materials, whether they are deposited on 



4 mud patch areas, heads of canyons, or the deep areas on the slope and 



5 rise are very similar types of compositions. 



6 Presumably this is all the same type or the same source material, 



7 the same source regime, which is then just mixed throughout the study 



8 area. One of the slides that Brad showed this morning, if you recall, 



9 showed that the sediment texture, the silt and clay content, had some 



10 interesting features. 



11 The one that I found over the past few years very interesting is 



12 the lobe of silty, I presume it's silty clay material, on the shelf area 



13 at the heads of the canyons. Oceanographer to some extent, certainly 



14 Lydonia Canyon. All of the hydrocarbon measurements are enriched in 



15 these areas as well . 



16 We've had several stations from the Georges Bank study, the first 



17 study that I summarized, which indicate that they are elevated by 



18 factors of two and three and up to five, elevated levels of total 



19 hydrocarbons and PAH's in these silt-clay lobes at the heads of canyons. 



20 One of the working hypotheses that still remains a working 



21 hypothesis is since this material is compositionally very similar to any 



22 of the depositional environments and compositionally similar to the 



23 slope hydrocarbons, that this material is sourced in the deeper 



24 environment. 



25 Through up-canyon transport and deposition at the heads of these 



26 canyons we are seeing hydrocarbons in a steady state throughout this 



27 area as well. Whether this is material being deposited or being 



28 transported down-canyon or whether it's material coming up canyon in 



29 transport, I'm not sure. 



30 It's probably a combination of both. I believe that this feature 



31 has been observed fairly persistently over the past several studies and 



32 that this still is a working hypothesis that the up-canyon transport is 



33 responsible for these depositional areas of fine-grained sediment and, 



34 of course, of hydrocarbons as well. 



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