Surficial Geology: 



Because of its underlying igneous bedrock terrain and relatively rugged 

 relief. Region 5 is characterized by surficial deposits of ground moraine 

 (till) covered sporadically with small, discontinuous bouldering moraine 

 deposits. 



In the northern part of the region, however, larger end moraines and ice- 

 contact deposits left on the surface of the interior lowlands have created 

 a dammed topography which has allowed thick peat deposits (up to 25 feet deep) 

 to accumulate (Cameron 1978) . Small peat and swamp deposits occur locally 

 along the coast (Timson 1978). 



The soils of this region are clayey, loamy or non-existent. 



Marine Geology: 



Sedimentation along this portion of the coast has occured primarily sub- 

 tidally owing to the relatively deep bathymetry. A number of fine-grained 

 estuaries occur in the regions (Union River, Narraguagus River estuaries), 

 but little investigation in these estuaries has taken place, particularly with 

 respect to sedimentation rates. Sedimentation rates within these estuaries and 

 the neutral tide-dominated or wave -dominated basins into which the estuaries 

 flow is low owing to the low topography which the rivers drain and the presence, 

 from Franklin Bay - east, of algal mats in the intertidal flats which would be 

 smothered by moderate sedimentation (Timson, in press) . 



Of note within this region is the only fjord in the eastern seaboard of 

 America - Somes Sound. The fjord lies along the southwest border of Mt. 

 Desert. 



Hydrology: 



The Union and Narraguagus Rivers are the major rivers draining Region 5 . 

 The Narraguagus River drains 601 km of terrain with an average discharge of 

 14.02 cu m/sec and extremes of 295 cu m/sec. The Union River (Ellsworth) 

 drains 383 km^ of terrain along the eastern border of the region with an 

 average discharge of 7.6 cu m/sec with extremes of 117 cu m/sec, (U.S.G.S. 

 1978). No sediment discharge rates are available for these rivers. 



Groundwater data for Region 5 indicates that bedrock yields are less than 

 in other regions (Caswell and Lanctot 1975) . This probably results from the 

 igneous nature of the bedrock but also from the sparseness of well data. 



Higher than normal bedrock yields do occur in Cherryfield, Bass Harbor, 

 and Southwest Harbor. 



Wells tapping surface groundwater are common in local ice-contact sand 

 and gravel deposits, particularly in the eastern portions of the region. 



(Continued) 



2-D-8 



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