Feltville Formation (NJ) - (Lower Jurassic) Olsen, P.E., 1980a[1] - Unit is covered by surficial deposits but identified through well logs (Stanford, 1991). Elsewhere unit is reddish-brown, or light-grayish-red, fine- to coarse-grained sandstone, siltstone, shaly siltstone, and silty mudstone, and light- to dark-gray or black, locally calcareous siltstone, silty mudstone, and carbonaceous limestone. Upper part of unit is predominantly thin- to medium-bedded, reddish-brown siltstone. Reddish-brown sandstone and siltstone are moderately well sorted, commonly cross-laminated, and interbedded with reddish-brown, planar-laminated silty mudstone and mudstone. Two thin, laterally continuous sequences (Jfg), each up to 10 feet thick of dark-gray to black, carbonaceous limestone, light-gray limestone, and medium-gray calcareous siltstone, and gray or olive, desiccated shale to silty shale occur near the base, and together with the red beds below, comprise the Washington Valley Member (Jfw) of Olsen (1980b). Gray bedsmay contain fish, reptiles, arthropods, and diagnostic plant fossils. Several inches of unit have been thermally metamorphosed along contact with Preakness Basalt (Jp). Thickness ranges from 450 to 483 ft.

All footprints here are from the early Jurassic Period (200 mya) from the Feltville Formation. The slabs here are red, blue, brown, and olive-green sandstones which were deposited during the formation of the Newark rift basin. Typical ichnotaxon list: Ameghinichnus n. sp.(advanced synapsid, possibly trithelodontid), Anchisauripus tuberosus (small to medium sized theropod dinosaur), Anomoepus scambus (ornithischian dinosaur), Batrachopus deweyii (crocodylomorph), Eubrontes giganteus (large theropod dinosaur), Grallator parallelus (small theropod dinosaur), Rhynchosauroides sp. (lepidosauromorphs), and others.