Sediments deposited by a middle-late Oligocene transgression are present as a thickening downdip wedge in the subsurface of the New Jersey coastal plain. Glauconitic sands and silts, designated as the Jobs Point formation, were deposited under inner mid-shelf depths (15 to 80 m). Middle-upper Oligocene glauconitic silts in the COST B-2 well which were deposited in outer shelf-upper slope depths (180 to 225 m) are a facies of the Jobs Point formation. The Oligocene transgression followed a major regressive event which occurred at the close of Eocene time. A regional hiatus resulted from this event.

Benthic forams in cores from the type wells of the Jobs Point cluster into three assemblages which represent biofacies of distinct depths (< 30 to 35 m; < 50 to 60 m; 45 to 80 m). The distribution of these biofacies in the Jobs Point shows an initial rapid transgression and a more gradual regression toward the top of the Oligocene sequence. The presence of the planktonic foraminiferal Globigerina ampliapertura Zone in the basal part of Oligocene sediments indicates that the transgression began about 32 m.y.B.P.

Structural-contour and isopach maps of the Jobs Point show that tectonic movements of the Salisbury Embayment and the South Jersey high influenced deposition of the Oligocene sediments.

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