Geologic map of New Jersey: Central sheet

Abstract

geologic information. L.M Bybell and G.W. Andrews provided age information of subsurface units. Members of the USGS Water Resources Division in Trenton, N. J. also provided a large amount of support to the project, notably Otto Zapezca. This group supplied support in the drilling of some of the coreholes and provided most of the geophysical logs. An integral part of the map was to produce detailed subsurface framework. Most of the drilling was done by the personnel from the Branch of Eastern Regional Geology primarily Donald Queen and Eugene Cobbs.The text for the various plates were reviewed thoroughly and intensively by Gregory Gohn of the USGS and Richard Dalton of the New Jersey Geological Survey. These outstanding reviewers improved the style and to a degree the substance of these texts. DESCRIPTION OF MAP UNITS (Plate 1)Coastal Plain Sediments Cohansey Formation (middle Miocene, Serravallian)--Sand, loose, white to yellow in most outcrops, locally gravelly and less commonly clayey. Locally stained red or orange brown by iron oxides. In a few areas, the sands have been ce*nented into large blocks of ironstone.This formation is the major surface unit in the central New Jersey Coastal Plain. The maximum thickness in the map area is about 200 ft. The Cchansey has been extensively eroded and stripped from large areas of the New Jersey Coastal Plain, particularly in the north; detached Cohansey outliers are common. In spite of its widespread nature, the Cohansey is poorly exposed because of its loose sandy composition, which causes it to slump easily. Fortunately, because of this same sandy nature, the Cohansey has been widely mined, and man-made exposures are common in many areas. In general, the Cohansey sands are crossbedded, although the style of crossbedding varies significantly depending upon th^ environment of deposition. Most of the crossbedding is trough type, especially in the non-marine channel fill deposits (Owens and Sohl, 1969, fig. 14A an-1 C), and the scale of the crossbeds varies from small to large. In some areas, plarsr bedding is well developed in sections having abundant marine burrows (generally clay-lined Ophiomorpha nodosa). Such marine-influenced beds (largely foreshore deposits) occur west of Asbury Park (Asbury Park quadrangle), near Adelphia (Adelphia quadrangle), north of the Lakehurst Naval Air Station (Lakehurst quadrangle), and at Juliustown (Columbus quadrangle) (Owens and Sohl, 1969, fig. 14D). Rarely, as near West Berlin (Clementon quadrangle), shell ghosts have been observed (Newell and others, 1988).Sands in the Cohansey typically are medium grained although the rar<?e is from fine to very coarse grained. The bulk of the sand is poorly to well sorted. Gravel beds are present in updip areas such as near New Egypt in the Atlantic Highlands and in the highlands near Bennegat in the southeastern corner of the map area. Most of the gravel is 0.5 to 1.0 in in diameter, but pieces to about 4 in in length are present. Most of the gravel is quartz with small amounts of black chert and...

Wilson Lake site

“…The Bridgeton Formation is mapped near Wilson Lake (Owens et al, 1995), and Bridgeton gravels were observed in the park capping minor highs. The Hole A gamma log suggests that coarse material is restricted to 10-18 ft (3.0-5.5 m).…”

Strontium-isotopic correlation of Oligocene to Miocene sequences, New Jersey and Florida

“…Pekar et al (Chapter 15,this volume) recognized at least five Oligocene sequences using shifts in benthic foraminiferal biofacies along with hiatuses delineated biostratigraphically or with Sr isotopes. The lower Oligocene (Sewell Point/To 1 cycle) is generally finer grained and characterized by outer neritic biofacies, whereas the upper Oligocene (Atlantic City/To 2 cycle) is generally coarser grained and characterized by inner (and some middle) neritic biofacies (Owens et al, 1995a;Pekar et al, Chapter 15, this volume). Thus, the Oligocene of New Jersey shows a general coarsening and shallowing upsection that marks a major change in sedimentation.…”

“…The Kw1 (Kirkwood 1) and younger Miocene sequences record shoaling-upward transitions from inner neritic and prodelta environments to delta front and near-shore marine environments. The lower Miocene Kw1 sequences (Kw1a and Kw1b) are the most extensive sequences in New Jersey and are exposed updip in the outcrop belt (Sugarman et al, 1993;Owens et al, 1995aOwens et al, , 1995b …”

“…Owens et al (1995a) mapped two subsurface Oligocene cycles, a lower Oligocene To 1 cycle and an upper Oligocene To 2 cycle, which approximately correspond to the Sewell Point and Atlantic City Formations (Pekar et al,Chapter 8,this volume). Pekar et al (Chapter 15,this volume) recognized at least five Oligocene sequences using shifts in benthic foraminiferal biofacies along with hiatuses delineated biostratigraphically or with Sr isotopes.…”

Clay mineralogy of the Cape May, Atlantic City, and Island Beach boreholes, New Jersey

“…Owens et al (1995b) and Owens et al, (1995a) informally divided the Kirkwood Formation into the Belleplain, Wildwood, Shiloh Marl and Kirkwood Formations. Miller et al (Chapter 14,this volume) retained the Kirkwood Formation in its original sense and applied the terms Belleplain, Wildwood, Shiloh Marl, and Brigantine Members to the formations of Owens et al (1995aOwens et al ( , 1995b. We follow the nomenclature of this volume to be consistent.…”