Time-correlative units in the overlap portions of the cores indicate that strata thicken (as much as 19% between cores separated by 3.3 km) from the hinged margin of the basin toward the border fault and/or intrabasinal normal faults and from the lateral edge of the basin toward its center; presumably basin subsidence varied similarly. These results are consistent with neotectonic studies of normal faults that have shown maximum displacement at the center of a fault, decreasing toward its lateral ends. Assuming a linear wedge-out constrained by the thickness changes between adjacent drill sites, we can infer the location of the pre-erosion edge of the depositional basin: ~7 km from the present-day basin edge in the Princeton area for the upper Lockatong Formation. Time-equivalent units of those recovered by the coring also crop out in two other fault blocks. If the intrabasinal faults are post-depositional, as has been traditionally assumed, the wedging determined from the core data predicts that the outcrop units should be ~100% thicker than the cored units in the fault block furthest from the drill sites, yet the outcrop units actually are only marginally thicker. This implies that at least the intrabasinal fault nearest the drill sites (Hopewell fault) was syndepositionally active.

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