INTRODUCTION 



General 



This report presents the data collected in the 

 course of an environmental baseline study off the 

 northern coast of Alaska. Part of the investigation 

 is focused on studying the present-day geologic 

 processes. Three goals were taken under consid- 

 eration: 1} To obtain a usable quantity of geologic 

 data in a little known environment, 2) to interre- 

 late oceanographic, biological, and chemical var- 

 iables with geologic processes, and 3) to examine 

 the stability of the present-day marine geologic 

 regime. At present only a small segment of the 

 data has been digested; this report will examine 

 the conclusions that can be reached. 



The area studied extends from Cape Simpson 

 on the west to Barter Island on the east and from 

 the northern coast of Alaska out to the base of the 

 continental slope (fig. 1). The Continental Shelf 

 in this area is essentially an extension of the broad 

 low coastal plain of Pleistocene and Holocene 

 silts, sands, and gravel (Payne and others, 1951). 

 The shelf break is remarkably shallow, occurring 

 at only 70 meters (Carsola, 1954). 



The marine geology of the region is poorly 

 known. Carsola (1954) reviewed earlier work and 

 presented the majority of information on the 

 marine sediments known until the present study. 

 More recently, the clay mineralogy has been con- 

 sidered by Naidu and others (1971), and the role 

 of ice as a geologic agent on the shelf has been 

 investigated by Kovacs (1972), Reimnitz and 

 others (1972a), and Pelletier and Shearer (1972). 

 Preliminaiy work on the recent geologic history 

 and sediment thicknesses in the near-shore area 

 was published by Reimnitz and others (1972b). 

 These studies have indicated a gently sloping 

 shelf with little topographic expression outside of 

 the extensive microrelief caused by drift ice in- 

 teracting with the bottom. 



Methods 



Three vessels were used to gather information. 

 During August and September of 1971 and 1972 

 fieldwork was accomplished from the U.S. Coast 

 Guard icebreaker GLACIER and from the 38-foot 

 research vessel NATCHICK of the Naval Arctic 

 Research Laboratory. The U.S. Geological 



Survey's 40-foot research vessel LOON gathered 

 information during August and September of 

 1971 and from July into September of 1972. The 

 location and type of geologic data from these 

 efforts are outlined in a report by Barnes and 

 others (1973). 



Most of the techniques used in collecting and 

 storing the samples have been outlined in Barnes 

 and others (1973). Coring devices used include 

 box corer, Hydroplastic corer, and a Ewing-type 

 piston corer with a 40-foot barrel and plastic 

 liner. (See Bouma, 1969, for a complete discus- 

 sion of these sampling devices.) 



Textural analysis of the sediments involved 

 standard techniques. Grain size of the gravel frac- 

 tion was determined by sieve analysis. The sand- 

 sized material was processed in a 2-meter Woods 

 Hole type settling tube (Schlee, 1966) calibrated 

 to sieves. Silt and clay fractions were analyzed by 

 the hydrometer method. Computer analysis of 

 size data was used to calculate component ratios, 

 Folk and Ward statistics (Folk and Ward, 1957), 

 Trask statistics, and standard moment measures. 

 Box cores were examined and radiographed using 

 techniques outlined by Bouma (1969). 



Suspended fine-grained sediment transport 

 was studied using turbidity measurements from a 

 transmissometer. These were supplemented by 

 Secchi disc readings. In addition, surficial water 

 samples of 1 to 4 liters were obtained and filtered 

 on preweighed filters for particulate matter. Dur- 

 ing 1971, 0.45 )Lt silver filters were used with only 

 moderate success owing to partial solution of 

 silver in sea water and an attendant loss in filter 

 weight . This error was corrected for by determin- 

 ing the loss in weight after back-flushing with 

 filtered demineralized water and microscopic ex- 

 amination of both the back-flushed filter and the 

 flushed filtrate for the efficiency of the flushing. It 

 is believed that the values obtained in this man- 

 ner are accurate within 0.2 mg/1 and are compar- 

 able to the data gathered during the following year 

 (1972). After testing several types of filters it was 

 found that 0.8 /U. membrane filters gave the most 

 consistent results (Bradley Larsen, 1972, written 

 communication); these were used during the 1972 

 field studies. During both the 1971 and 1972 

 seasons the sea-water samples were carefully col- 

 lected to avoid any contamination by the research 

 vessel. A standard volume (usually 4 liters) was 



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