Magothy formation Unconformity Raritan formation Great Unconformity between Cretaceous and Trias There is no complete section exposed. Sequence can be made out only by careful piecing together of scattered outcrops. The Raritan formation is best exposed in the clay district around Raritan River. Here there is the following section, top downward: Sand bed 75 feet Amboy stoneware clay 25 feet Sand bed 20 feet South Amboy fire clay 20 feet Sand bed including "so called" "feldspar" and "kaolin" 45 feet Woodbridge brick and stoneware clay } 80 feet Woodbridge fire clays Sand bed 25 feet Fire and terra cotta clays 0-30 feet Higher members in the series will be seen on Friday. Note on Tertiary Deposits The Tertiary deposits of New Jersey are chiefly sands, with some clay beds. The lower member- the Kirkwood sand- is known to be of Miocene age. The upper member- the Cohansey sand- is thought to be Pliocene, but without definite proof. Both members contain lenses of clay. The highest hills of South Jersey are capped with the Beacon Hill gravel, regarded as younger than the Cohansey but probably Tertiary, and the correlative of the Lafayette, Note on the Pleistocene The non-glacial Pleistocene deposits are the Bridgeton, Pensauken and Cape May, the first being the oldest. They are generally orange colored or yellowish brown sand and gravel, ranging in thickness up to 30 feet, probably fluviatile in origin; separated from each other in age or by periods of erosion. The differentiation between them is partly lithologic but mainly topographic. In general they agree with the Sunderland, Wicomico and Talbot formations of further south. ------ 8 A. M. Leave hotel for trip through the clay district about Perth Amboy, Woodbridge, and South Amboy. Near Perth Amboy and Woodbridge sections frequently show (1) Glacial till (Wisconsin) (2) Pensauken gravel (3) Cretaceous. Near Woodbridge, the Woodbridge fire clay is dug extensively. -8-