SUPPLEMENTAL EVIDENCE LENDS CREDENCE TO THE WORKING HYPOTHESIS OF GLACIATION ON THE NEW JERSEY COASTAL PLAIN

A presentation entitled "Projections And Evidence Of Pre Wisconsin Glaciation On The New Jersey Coastal Plain" was given 3/14/05 at the NE/GSA meeting at Saratoga Springs, N.Y. In it were listed and illustrated an array of features and characteristics of the "interglacial" Pensauken and Bridgeton deposits south of the Wisconsin moraine. These features when taken together, were claimed to be of a glacial phenomenon. Further evidence given here adds to that claim. The area considered is the lowland from Raritan Bay to Trenton and the piedmont to the west.

Despite the recognition of the continental glacial deposits in N.J. (formerly attributed to high sea levels) these coastal plain deposits, in the late 1800s, were somehow still attributed to high sea levels of over 200 ft. In order to explain various confusing features and characteristics of these deposits, origins were later attributed to both partly marine and more-so to large rivers with ice rafting of large boulders. Now their origins are just attributed to high volume swift rivers. Theoretically (but yet unexplained) these large swift rivers, from sea level at Raritan Bay, had to aggrade up, over 200 ft., unchanneled, and down the coastal plain at 200 ft. elevs, for 90 miles, burying valleys with sands, gravels, and boulders.

Neumann of Princeton Univ. (1980) described the Pensauken deposit at Rocky Hill north of Princeton, as having many cobbles and boulders up to 1.5 meters long with several sets of striations. The Rocky Hill Range, to the south, is a diabase intrusion. At elev. 370 (and 220 ft above the striated Pensauken boulders) pebbles up to 4 inches were found. In the older glacial drift areas of N.J., such pebble deposits have been identified as glacial. From these hilltops down to the countryside, some large rounded, smooth boulders are found, seemingly planed on different sides, like known glacial boulders. One such trap boulder was found S.E. of Princeton (just E. of the Raritan/Delaware Canal) striated on one narrow wedge shaped side. This striated boulder is 2 miles S.E. of the nearest diabase outcrop from which it was lifted and striated by ice, 17 miles south of the nearest Wisconsin moraine. It was not striated and then ice rafted from the north, beyond the moraine, as the many other large boulders are thought to have been. Much such evidence is out there to be readily found.