Pensauken Formation — Local Details. 145 



toward Englishtown. The area was somewhat amphitheatral 

 in shape, with its rim at about 170 feet, and its low point at 

 Englishtown, at about no feet. The material here which is 

 regarded as possibly Pensauken contains notably more that was 

 derived from the Cretaceous, than does the gravel at Gravel 

 Hill and on the divide northwest of Englishtown. If early 

 post-Pensauken drainage from the Matawan-Freehold region 

 went to New Brunswick, and thence by way of Bound Brook 

 through Kingston to Trenton, the course was very roundabout. 

 If the present course of the Raritan to the ocean was developed 

 after the gravel west of Englishtown was deposited, the change 

 would have greatly facilitated erosion in the Englishtown region. 



North of Deep Run. — The gravel remnants in this region 

 which seem most confidently correlated with the Pensauken are 

 those at 120 to 150 feet in the vicinity of Morristown, Morgan- 

 ville, and Browntown. The Cretaceous surface beneath the Pen- 

 sauken at South Amboy and Old Bridge and Jamesburg, it will be 

 remembered, has an elevation of about 90 feet. The gravels re- 

 garded as probably Pensauken about Morganville have an eleva- 

 tion of about 150, suggesting a Cretaceous surface sloping from 

 150 feet at Morganville to 90 feet at Old Bridge, just before the 

 deposition of the Pensauken. No stream such as Matawan Creek 

 or Cheesequake Creek seems to have been located along the 

 strike of the Cretaceous beds at that time, and the creeks men- 

 tioned above seem to be of post-Pensauken origin. 



Two miles northwest of Matawan, there is an elongate divide 

 (Morristown-Jacksonville or Cheesequake) at an elevation of 

 130 to 150 feet, which has a gravel cap not less than 12 feet 

 thick. Stratification is distinct, but assortment poor. Many 

 pebbles stand on end, indicating rough or swift waters. Quartz 

 and ironstone are both abundant, the latter partly in large slabs. 

 The sand, which is largely beneath the gravel, has much glau- 

 conite. The gravel is very like the uppermost member of the 

 Pensauken at South Amboy. 



About the headwaters of Tennents Brook, especially on the di- 

 vide between Browntown and Morganville, there are numerous 

 hilltop gravel caps which are perhaps to be correlated with the 



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