1 82 Quaternary Formations of Southern New Jersey. 



This section is like sections farther north except that the clay 

 here is heavier. Except for the clay, the section is fairly nor- 

 mal for the region. 



A few rods northeast of Edgewater Park Station, just north 

 of the railway, there is gravel, containing even small bowlders. 

 Pieces of Triassic shale, granite, and trap occur here, in addi- 

 tion to the sorts of rock enumerated above. It is worthy of 

 note that the granites and greywackes do not look so fresh as 

 those of the Trenton gravels generally. Similar gravel occurs 

 in Beverly, and has been seen in temporary excavations down 

 to depths of 10 feet. It may be seen in excavations generally 

 between Edgewater Park and Delanco, near the river. One and 

 a quarter miles southwest of Beverly depot, sections have been 

 seen showing Trenton gravel (Cape May) over Pensauken, if 

 interpretations are correct. 



The gravel containing greywacke is seen again about River- 

 side, and at Riverton in the south bank of Pompeston Creek. 

 Other exposures in Palmyra show greywacke gravel under the 

 surface loam. To the southward, the sorts of pebbles character- 

 istic of the Delaware glacial gravels become fewer and fewer. 



From Burlington to Pensauken Creek, most of the Cape May 

 formation which can be assigned to the Delaware Valley proper 

 has a surface altitude of 30 to 40 feet, but in many places its 

 surface has been built up by eolian sand to elevations somewhat 

 above its original level. 



Rancocas Creek. — The basin of this creek resembles the basin 

 of Crosswicks Creek in some respects. The form of the basin, 

 like that of Crosswicks Creek, is related to the character of the 

 underlying' formations. It is narrow where it crosses the marl 

 slefries, but expands greatly above in the vicinity of Mount 

 Holly. Arneys Mount, Mount Holly, and Mount Laurel are 

 isolated elevations along the outcrop of the marl series, in place 

 of the high belt in the corresponding position on Crosswicks 

 Creek. The low flat in the basin of the upper Rancocas is 

 larg'er than that in the upper basin of Crosswicks Creek, and it 

 opens much more widely toward the Delaware lowland. These 

 features are in keeping with the larger size of this creek, as 

 compared with Crosswicks. 



