Pensauken Formation — Local Details. 119 



small bowlders (up to 1 foot) being abundant. These cobbles 

 and small bowlders have been gathered in large numbers along 

 some of the fences. Between Robbinsville and Yardville, similar 

 stones are common over the surface. They are the relics of 

 Pensauken that is gone. 



The characteristics of the formation in the vicinity of Robbins- 

 ville hold to the northwest; but the materials become coarser in 

 that direction, and the proportion of granitic and Triassic ma- 

 terial increases, though not uniformly. 



A mile and a half south of west of Hamilton Square, at the 

 road corners, there is a bowlder 4 feet in diameter. The surface 

 hereabout is characterized by occasional undrained hollows, drift 

 fashion. Raritan clay lies close beneath, and its movement, 

 resulting from its plasticity, is perhaps responsible for this element 

 of the topography. 



Between Assanpink Creek and Miry Run. — The Pensauken 

 here has a surface altitude ranging from 70 feet or so up to 100 

 feet or slightly above. Locally, the formation is hard to dis- 

 tinguish from its Cretaceous base, especially where the latter is 

 sand. 



Shrewsbury, Wrightsville, and Nezv Sharon. — About Shrews- 

 bury and Wrightsville there are, within a few miles' radius, a 

 number of gravel-capped hills. The gravels are of southeasterly 

 origin, and their age is somewhat uncertain. Knapp regards 

 them as probably Pensauken, but they may be older. The hill- 

 tops about Shrewsbury range from- 140 to 155 feet, and those 

 about Wrightsville up to 190 feet. Larger areas of possible 

 Pensauken occur just south of Shrewsbury and Egg Tavern, and 

 at Wrightsville. These larger patches are on slopes, and are 

 younger than the hilltop caps. Their exact age does not appear 

 to be determinable. If the hilltop caps are Pensauken, these are 

 younger; if the hilltop caps are older, these may be Pensauken. 



On the divide at Davis Station, and extending both east and 

 west, is a body of non-arkose Pensauken at an elevation of 140 

 to 148 feet. One section seen here shows: 



