Textural changes, in the fine-grained cores, consisted of thin laminae and 

 lenses of silty and sandy material, soft liquid zones, and thin layers of hard bluish- 

 gray clay. Some cores contained layers, blebs, or balls, composed of hard, seem- 

 ingly dry, yellowish to brownish clayey silt and silty clay, in many cases banded 

 and/or stained with limonitic material . 



Cores containing coarser grained material and more pronounced textural changes 

 than those mentioned above came from the northern part of the bay between Long 

 Island and Searsport and the entrance to the bay. 



Between Searsport and Long Island several of the cores contained relatively 

 thick layers of sand and silty sand with scattered pebbles and pebbly zones. The 

 sediments tended to increase in coarseness toward the bottom of the cores. Shallow 

 penetration of the corer and the loss of the lower portion of some of the cores also 

 were indicative of coarser sediments with depth below the bottom in this area. 



In the entrance to the bay, the cores generally showed more variability than 

 in the northern part of the bay; however, the changes were not as marked, and 

 the cores were finer grained on the whole. Core 190, taken on the eastern slope 

 of the topographic depression in the entrance to the bay, contained many slightly 

 sandy, silty-clay layers which had a sharp lower contact and graded upward into 

 silty clay or finer texture. Core 126 from West Penobscot Bay also displayed this 

 type of bedding. The cores showing this weakly graded bedding may owe this con- 

 dition to the settling of a slurry of sediments which were thrown into suspension 

 by slumping of earlier deposits. 



The coarse-grained sediment cores sampled in the north-central part of the bay 

 reflect the nearness to the source of sediment, the Penobscot River. The cores are 

 finer grained at the top indicating a decrease in energy conditions with time at the 

 site of deposition. The finer grained cores with less significant changes in lithol- 

 ogy are found in the remainder of this northern sector of the bay. Many of these 

 cores contained open worm burrows and fragments of wood, as well as thin beds of 

 coarser material . These features suggest shallow estuarine or tidal flat environments 

 with rapid deposition taking place periodically (Hantzschel, 1939). 



in the central and southern parts of the bay, the sediments are generally fine 

 grained and uniform with depth below the water bottom. These sediments represent 

 deposition under relatively uniform environmental conditions upon which were 

 superimposed small scale and short lived variations. These fluctuations in the 

 environment account for the silty and sandy laminae found in many of the cores. 

 The black laminae found in nearly all of the cores from this portion of the bay may 

 be due to increased rates of deposition. The uppermost layers of estuarine sediments 



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