top. Thirteen (62 percent) of the 21 cores for which samples from the 

 top and 0.3-meter levels were analyzed show this size decrease character- 

 istic. In comparison, seven (33 percent) show no change in grain-size 

 slope and only one (5 percent) becomes coarser upward from 0.3 meter. 

 This pattern is probably an artifact of the coring technique. Surface 

 sediments are high in water content and during extrusion of the core 

 liner from the barrel, the core is held horizontally. This results in 

 some mixing of the uppermost sediments and grains are probably size- 

 fractionated due to differential settling rates. 



Vertical textural trends of the shoal are somewhat enigmatic in that 

 trends of adjacent cores sometimes correlate. Of the three cores (15, 4, 

 and 5) collected along the axis of Isle of Wight shoal, 15 and 4 have an 

 overall upward coarsening trend. The two cores differ from each other, 

 however, in that core 15 is significantly finer grained than core 4 at 

 every level. Cores 4 and 5 appear to be closely related in overall size 

 and trend with a distinct coarsening from -1.2 to -0.3 meter (-4 to -1 

 foot) which may represent a single depositional "event." The alternatives 

 are that the trend is coincidental or that the trend is a characteristic 

 result of depositional processes on the shoal crests. 



Size trends from cores 44, 49, and 48 on Great Gull Banks (Fig. 41) 

 bear little resemblance to each other, with only one exception. A coarse 

 layer or event occurs at about -1.2 meters in cores 49 and 48. This layer 

 does not appear in core 44, and the level (-2.7 meters) of the one coarse 

 layer in that core was not sampled in the other two cores. The three 

 cores (56, 54, and 21) collected from shoal C 2 -C 1 (north of Little Gull 

 Banks) also show vertical size trends that appear independent of one 

 another. Core 56 remains essentially constant in mean grain size; core 

 21 distinctly and consistently coarsens upward to -0.3 meter. Generally, 

 the three cores contain finer sands than other cores collected from off- 

 shore linear shoals (Fig. 41). Single cores taken from offshore shoals 

 also show variations as a group in vertical size trends. Core 17 shows 

 subtle upward coarsening; core 6 shows subtle upward fining; and cores 

 11 and 72 exhibit no distinct trends. Core 6, from Fenwick shoal, was 

 sampled at 0.5-meter intervals down to 1 meter and at 0.3-meter intervals 

 down to -2.4 meters. Examination of mean grain-size data (Fig. 41) shows 

 that the increased sampling density had little influence on the shape of 

 the curve, although in other cores a close sample spacing may be necessary 

 to delineate true trends. 



Some cores from the shoreface and shoref ace-shoal transects (Fig. 42) 

 were not sufficiently sampled to evaluate the size trends. Of the six 

 individual cores (Fig. 42, top), only cores 13 and 59, which are both 

 distinctly finer grained than the rest, show an overall upward-coarsening 

 trend. Cores 24, 25, 39, and 40 display upward-fining trends. For the 

 most part, the intracore variations in mean grain size are larger than 

 those between cores and often exceed one whole phi class. Comparison 

 of textural trends in four cores collected along the axis of Ocean City 

 shoal (Fig. 42, lower) show little similarity in mean grain size or trend, 

 with the exception of a fine layer or event in cores 32, 31, and 30 at the 



102 



