approximates 35 feet and two primary slope directions are indicated. If these are 

 sedimentary structures, then westerly flow apparently preceded easterly transport. Material 

 underlying the crossbeds is flat-lying or dips slightly easterly and acoustically appears more 

 massive and continuous than overlying sediment. 



Horizontally stratified Holocene material is shown in Line B, but of slightly greater 

 thickness, on top of crossbeds which appear to be the result of complex multidirectional 

 stream flow. Smaller scale internal structures within crossbedded units are not discernible on 

 the records. At the southern margin of the crossbed area, Line C is similar to the preceding 

 two lines but, in addition, shows more cut and fill structures thought to represent stream 

 channels buried by later deposition. Such channel-like structures are common on many of 

 the records and some appear to be in continuous alignment over short distances with 

 present-day drainage channels such as the Navesink River. The log of Coast Guard boring 

 No. 2 from Scotland Light (Table 3) agrees with the independent reconstruction of seismic 

 profile C. The log, showing a water depth of 49.5 feet, indicates that from the sea floor 

 down to a subsea depth of about 100 feet the material consists of fine to medium sand with 

 varying percentages, of pea gravel. At —100 feet there is a sharp lithologic break which 

 correlates with the Coastal Plain erosion surface shown in Line C. The top 15 feet of Coastal 

 Plain strata from the log description apparently are stiff silts and clays underlain generally 

 by medium to coarse brown sand and pea gravel. Because of the general nature of the log 

 description no correlations with specific Coastal Plain formations are possible. 



A horizontally bedded 12-foot thickness of Holocene sands overlying a 40-foot-thick 

 sequence of crossbed material is shown in Line 1, Figure 8. Inclinations of foreset beds at 

 the north indicate a southerly transport direction while the chaotic internal structures to the 

 south are indicative of cut and fill associated with stream channel migrations. The 

 approximate maximum lower limit of crossbed strata is —100 feet MLW, which here 

 represents the Coastal Plain erosion surface. The same stratigraphic sequence (Line 1) is 

 shown in Line 2, except that the Holocene material at the north end is about 10 feet thick 

 and thickens to about 30 feet to the south. The underlying crossbeds are inclined northward 

 and indicate either a northerly transport system or an extraneous component of a southerly 

 directed system. Buried and filled stream channels are evident and their position indicates 

 they postdate the forest beds. 



Attempts have been made to determine major stream channel orientations in the 

 crossbed area east of Sandy Hook by plotting crossbed dip directions and by construction of 

 crossbed isopach maps, but the structures are so complex that regional trends are obscure. 



A contour map representing the surface topography of the crossbedded sands using mean 

 low water as the datum surface is shown in Figure 6. The contours indicate that the surface 

 has a general north-south strike with a gentle slope to the east. There are smaller variations 

 in relief but difficulty was sometimes encountered in determining the top of the sands on 

 the records because of masking by the bubble pulse. Such a regional surface topography 

 may have resulted from a high degree of marine reworking of the fluvial material by 

 transgressing seas in post-Wisconsin time. 



30 



