Figure Page 



3. Concentration of suspensates in the surface waters off northern coast of Alaska 



during August-September, 1972 198 



4. Turbidity of surface waters off northern coast of Alaska during August- 



September, 1971 199 



5. Turbidity of surface waters off northern coast of Alaska during August- 



September, 1972 200 



6. Idealized light attenuation profile derived from transmissometer profiles recognized 



in the Alaskan Beaufort Sea, during summer 1971 201 



7. Texture of the surface sediments expressed in mean diameter of Folk and Ward (1957) . . 202 



8. Distribution (In per cent) of gravel in the surface sediments of the Alaskan 



Beaufort Sea 203 



9. Sediment sorting of the surface sample determined by Folk and Ward (1957) 204 



10. Scatter plot of mean diameter and sorting of surface sediment samples 205 



11. Sedimentary environments as determined by mean diameter and sorting index of 



figure 9 ' 206 



12. Radiograph of box core (inshore facies) sample taken at 18 m at station 46 



north of Colville River, 1972 207 



13. Radiograph of box core (midshelf facies) sample taken at 28 m between Canning and 



Sagavanirktok Rivers, 1971 208 



14. Radiograph of box core (shelf break facies) sample taken at 130 m northeast of 



Sagavanirktok River, 1971 209 



15. Radiograph of box core taken from base of slope (1640 m) during 1971 210 



16. Radiograph of box core taken from the side of and ice gouge north of Prudhoe 



Bay, 1971 211 



17. Bottom photograph of the central shelf (33 m) showing older ice gouging 212 



18. Bottom photograph of the central shelf showing recent ice gouging 213 



Mercury in the Environs of the North Shelf of Alaska 



Figure Page 



1. Mercury (ng/g dry) in sediments of coastal waters of Beaufort Sea 237 



Aspects of Size Distributions, Mineralogy and Geochemistry of Deltaic and 

 Adjacent Shallow Marine Sediments, North Arctic Alaska 



Figure Page 



1. Index map showing the area of study and locations of sediment samples. All sample 



locations except 12A, 4B and HB series, depicted by solid black dots have 



a prefix AJT.The depth contours are in meters 263 



2. Map of Colville Delta showing sample locations. The depth contours are in meters .... 264 



3. Gravel-sand, silt and clay plots 265 



4. Phi Mean Size (Mz) versus Sorting (cri) plots of sediments. Data for the delta coastal 



beach and the Colville River environments were taken from Dygas et al. (1971) .... 266 



5. Phi Mean Size (Mz) versus Skewness (SKi) plots of sediments. Data for the delta coastal 



beach and the Colville River enivronments were taken from Dygas et al. (1971) .... 267 



6. Variations of clay mineral assemblages in the Colville River 268 



xii 



