Evaluating the stratigraphic response to eustasy from Oligocene strata in New Jersey
- 1Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964-8000, USA
- 2Department of Earth and Environmental Sciences and Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964-8000, USA
- 3Department of Geosciences, Western Michigan University, Kalamazoo, Michigan 49008, USA
- 4Department of Geological Sciences, Wright Labs, Rutgers University, Piscataway, New Jersey 08854, USA
Abstract
Previously published Oligocene eustatic records are compared with observed stratigraphic architecture at the New Jersey continental margin in order to evaluate the stratigraphic response to eustatic change. Lower to mid-Oligocene sequence boundaries (33.8–28.0 Ma) are associated with relatively long hiatuses (0.3–0.6 m.y.), in which sedimentation in many places terminated during eustatic falls and resumed early during eustatic rises. Upper Oligocene sequence boundaries are associated with relatively short hiatuses (<0.3 m.y.), and provide the best constraints on phase relations between sea-level forcing and margin response. The interval represented by each upper Oligocene sequence varies in dip profile. At updip locations, landward of the clinoform rollover in the underlying sequence boundary, sedimentation commenced after the eustatic low and terminated before the eustatic high (with partial erosion of any younger record). At downdip locations, sedimentation within each sequence was progressively delayed in a seaward direction, beginning during the eustatic rise and terminating near the eustatic low. Combining data from all available boreholes, ages of sequence boundaries (correlative surfaces) correspond closely with the timing of eustatic lows, and ages of condensed sections (intervals of sediment starvation) correspond with eustatic highs.
Footnotes
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- Accepted October 4, 2000.
- Received June 13, 2000.
- Revision received October 2, 2000.
- Geological Society of America
