1. Particulate transport varies markedly from 

 year to year, depending on the vigor of the open 

 season circulation, the occurrence of storms, and 

 the extent of ice cover over the shelf. Overall 

 values of particulate matter are similar to those 

 found at lower latitudes. 



2. Vertical turbidity layering seen over the 

 shelf can be ascribed to a) river runoff, b) ice melt 

 water, c) a bottom turbid layer, and d) Arctic 

 ocean water. 



3. The sediments reflect the influence of both 

 water (waves, tides, and currents) and ice (goug- 

 ing and rafting). 



4. The shelf sediments can be broken into 

 three basic types: 1) A laminated sand and mud 

 interspersed with pebbles occurring on the inner 

 shelf in the area where current reworking and ice 

 action are both prevalent. 2) Ice-mixed pebbly 

 mud occurring on the central shelf and in inshore 

 areas where ice gouging homogenizes the sedi- 

 ments. 3) Muddy gravels, underlain by laminated 

 muds found dominantly along the shelf edge. The 

 gravels are tentatively ascribed to ice-rafting. 



5. The importance of modern ice rafting of 

 sand and gravel is still undetermined. Ice rafting 

 of fine grained (aeolian?) materials appears to be 

 a common mechanism and accounts for the major- 

 ity of "dirty" ice observed over the shelf. 



6. Arctic shelf sediments are not dominantly 

 relict as previously reported in the general litera- 

 ture. However, contrary to some reports, river 

 sediments are not being ice rafted to depositional 

 sites in the Beaufort Sea. 



7. Geochemical studies show essentially no 

 anomalously high values of petroleum-like sub- 

 stances or of some of the more common toxic 

 heavy metals. 



ACKNOWLEDGMENTS 



Erk Reimnitz has provided continual stimulat- 

 ing discussion and has served as co-worker. I 

 wish to express my appreciation to my fellow 

 scientists, and to the captain and crew of the 

 GLACIER, without whose efforts this study could 

 not have been conducted. The Naval Arctic Re- 

 search Laboratory generously furnished the 

 NATCHIK and her crew for our inshore studies. 



James V. A. Trumbull withstood the rigors of 

 small-boat operations and collected most of the 

 inshore samples. T. Forgatsch, C. Gustafson, P. 

 Malin, R. Patrick and A. R. Tagg aided in the 

 collection and reduction of data. Stimulating dis- 

 cussions were provided by E. Reimnitz and A. S. 

 Naidu. Part of this work has been supported by a 

 NASA contract S-70243AG to work with ERTS-1 

 imagery. 



Tom G. Ging and Vernon E. Swanson per- 

 formed the organic chemical analysis; Kam Leong 

 determined the heavy metal contents; and 

 Gretchen Luepke studied the mineralogy. Their 

 assistance is appreciated. Robert Rowland and 

 Paul Carlson critically read the manuscript and 

 suggested many improvements. 



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