Tinton Formation

Tinton Formation - Sand, quartz and glauconite, sideritecemented, indurated, reddish-brown to dark-gray. The Tinton was extensively dissected prior to deposition of the overlying Hornerstown Formation. Unit can be traced in the subsurface only as far downdip (south) as the Freehold area, Monmouth County. The Tinton in the Freehold core is about 6 m (20 ft) thick and thickens to the east where at Rumson, Monmouth County, it is 12 m (40 ft) thick. The Tinton unconformably overlies the Kc4 cycle. The Tinton is more quartzose to the west and more glauconitic to the east. The unit represents an incomplete cycle of sedimentation as it consists only of subtidal marine beds and lacks nearshore sands. Siderite cement, which imparts the hardness to the Tinton, is irregularly distributed throughout the unit. Because of its extensive induration, sand and clay mineralogy was not determined. Gamma logs of the Tinton, because of the widespread presence of siderite cement in the matrix, have a relatively high intensity and are similar in shape to gamma logs for clayey units. No fossils were found in subsurface samples of this formation, but fossils from outcrops indicate a late Maastrichtian age.