-16.8-meter (-55 feet) water depths, to more than 6.1 meters below lake 

 floor farther offshore. Cores 14 and 15 from this segment contain clean, 

 medium sand. Good prospects for sand borrow exist throughout the segment, 

 especially lakeward of the 15.2-meter isobath. 



j . Segment 10 . The lake floor in this segment is mostly smooth but 

 contains some low ridges (profile 10, App. A). The blue reflector appears 

 to vary from to about 4.6 meters below the lake floor. Eight cores from 

 this segment (cores 16 to 23) contain clean, fine to medium sand indicat- 

 ing large quantities of suitable sand are distributed throughout the 

 segment. 



k. Segment 11 . Several ridges with up to 3.1 meters relief occur 

 in segment 11 (profile 11, App. A). The blue reflector is not evident 

 inshore, but appears offshore where it crops out between the ridges. 

 Cores 24, 25, and 26 from this segment contain 1.2 to 3.1 meters (4 to 

 10 feet) of clean, medium sand overlying fine sand. The best prospects 

 for sand appear to be in the ridges. 



1. Segment 12 . The lake floor in this segment is predominantly 

 smooth; however, it is interrupted by a series of sand waves with up to 

 1.5 meters of relief distributed throughout the segment (profile 12, 

 App. A). The blue reflector is not apparent over most of this segment. 

 Cores 27 to 32 contain clean, fine to medium sand. Core 30 also has a 

 0.6-meter layer of sandy pea gravel. There appears to be good potential 

 for suitable sand in this segment. 



m. Segment 15 . A marked change in the character of the bottom and 

 subbottom occurs in this segment. The lake floor is smooth to irregular 

 with relief up to 3.1 meters. The topography is much less regular than 

 in the ridge and swale areas to the north, and the lake floor along pro- 

 files 13A and 13B (App. A) has a jagged rather than smooth texture. Sub- 

 bottom reflectors are fragmentary or missing in most of the segment; 

 however, on line 164 the lake floor is underlain by a section of paral- 

 lel, closely spaced reflectors that are somewhat distorted (profile 13A, 

 App. A). Cores 33 to 46 from segment 13 are predominantly sand but gray 

 clay and silt underlie the sand layer in seven cores. Gravel occurs in 

 four cores. The surface sand layer is thickest (3.1 meters) at core 36 

 which is probably the best area for obtaining sand in segment 13. The 

 gravelly sediments which occur in cores 33, 41, 42, and 44 are hetero- 

 genuous in size, mixed with sand and silt, and appear to be thin till 

 deposits. The upper 0.6 meter in core 42 consists of clean, well-sorted 

 granules and small pebbles. This deposit may be of value as construction 

 aggregate. 



n. Segment 14 . In this segment the lake floor again becomes rela- 

 tively regular and smooth but contains some ridges with up to 3.1 meters 

 relief (profile 14A and 14B, App. A). The blue reflector is not apparent 

 in most places and where evident it lies close to the lake floor. Cores 

 47 to 52 contain clean sand and the clay, silt, and gravel deposits oc- 

 curring in segment 13 either do not extend into this area or were missed 



27 



