V. ANALYSIS OF SURVEY DATA 



A. Sediments of Penobscot Bay 



For convenience in discussing the bottom sediments, the survey area was 

 arbitrarily divided into five parts as follows: 



1 . Northern part of the bay. 

 North of 44*20' N. 



2. Central part of the bay, including West Penobscot Bay and 



the northern part of East Penobscot Bay. 

 44«'20' to 44*10' N. 



3. Southern part of the bay, excluding East Penobscot Bay. 



44*10' to44*05'N. 



4. The entrance to the bay. 



44*05' to44*00'N. 



5. The approaches to the bay. 



South of 44*00' N. 



In general, from Searsport to south of Rockland the sediment cores were silty 

 clays. South of 44*05'N ., in the entrance and approaches to the bay, the fine- 

 grained sediments were confined to depressions between bedrock or bedrock thinly 

 covered with sand or gravel . 



The fine-grained sediments are olive-gray, silty clays with very small amounts 

 of fine sand and occasional pebbles. The cores, most of which were over 10 feet 

 long, were usually uniform in color and grain size. Over two-thirds of the cores, 

 however, contained thin beds and laminae of dark gray to black material . They 

 usually occurred in the top foot, the top and bottom, and also throughout the length 

 of several of the cores. Samples of the dark layers showed little textural difference 

 with surrounding sediments. It is suspected that the dark color is due to small amounts 

 of organic material . Analyses, however, were not made to determine the organic 

 content of the samples. After drying, the dark layers could not be detected in the 

 core . 



Small percentages of shell, usually as broken fragments scattered throughout 

 the core rather than confined to particular layers or zones, were found in many of 

 the cores. Open worm burrows were found in several cores. The worm burrows 

 crossed color and textural changes without destroying the stratification of the sed- 

 iments. Small amounts of woody material also were found in a few cores. 



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