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Maastrichtian ammonites from the Hornerstown Formation in New Jersey

W. J. Kennedy·W. A. Cobban
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Abstract

The base of the Paleocene Hornerstown Formation at the Inversand pit and certain other localities in New Jersey yields a diverse phosphatised fauna of Maastrichtian age, including the ammonites Pachydsicus ( Neodesmoceras) mokotibensis Collignon, 1952, Sphenodiscus lobatus (Tuomey, 1854), Baculites spp., and Eubaculites carinatus (Morton, 1834). S. lobatus is known from the older Red Bank Sand and Tinton Sand in New Jersey; the other species are known only from the basal Hornerstown. Occurrences at the Inversand pit are regarded as either reworked or remainié, although details of Cretaceous/Paleocene boundary events have been destroyed by pervasive burrowing that pipes the Hornerstown down into the underlying Navesink Formation.

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BibTeXRIS

W. J. Kennedy, W. A. Cobban. 2016-05-20. Maastrichtian ammonites from the Hornerstown Formation in New Jersey. https://doi.org/10.1017/s0022336000023842

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