Pensauken Formation — Local Details. 117 



where it was not continuous, the broad valley of Assanpink Creek 

 extended eastward far beyond the line where the scarp would 

 have been, and the arkose Pensauken was carried up this valley 

 to New Sharon and beyond. The northern material (arkose, 

 red shale, etc.), is chiefly at the base of the formation, nine- 

 tenths of it probably in the lowermost 5 feet. It is clear that the 

 northerly material was the first to come into the region, but 

 it soon gave place to local material from the southeast. The 

 belt within which arkose Pensauken occurs here is greatly 

 widened, as compared with the area farther s'outhwest. The 

 great widening occurs at Crosswicks Creek, and the arkose phase 

 of the formation extends east to Extonville and New Sharon. 



Near Crosswicks and Doctors creeks. — Between Crosswicks 

 Creek and Doctors Creek, south of Allentown, there is a large 

 area of Pensauken, the surface of which has a maximum alti- 

 tude of 126 feet. Its base has an elevation of about 60 feet near 

 the stream, and about 90 feet back from i-t. The pre-Pensauken 

 valley here appears to have been rather wide, and shallower than 

 the corresponding valley of the Rancocas. The formation here 

 has a thickness of about 30 feet. A bed containing coarse cob- 

 bles probably lies at its base, for about the borders of the area, 

 cobbles appear where the body of the formation has been re- 

 moved. Exposures show the usual arkose gravel and sand on 

 Cretaceous clay. A mile south of Allentown, arkose sand occurs 

 up to the top of the 126-foot hill. The surface of part of this 

 area is mantled with eolian sand and loam, which conceals the 

 true Pensauken material beneath. 



In the village of Allentown, what appears to be Pensauken 

 gravel has been seen poorly exposed in the south bank of the 

 creek. The material is more or less cemented at the level of the. 

 pond, 60 to 65 feet. This and some other exposures farther 

 down the creek suggest that Pensauken material may lie below 

 the Cape May deposits here. 



There is a considerable area of Pensauken east and northeast 

 of White Horse, rising above the 90-foot level. It rests on the 

 Raritan formation, as seen in numerous exposures. Its surface 

 declines to the northwest, and the formation passes beneath the 



