Sea-Level Estimates for the Latest 100 Million Years: One-Dimensional Backstripping of Onshore New Jersey Boreholes

Abstract

Backstripping analysis of the Bass River and Ancora boreholes from the New Jersey Coastal Plain (Ocean Drilling Project Leg 174AX) provided new Late Cretaceous sea-level estimates and tested previously published Cenozoic sea-level estimates. Amplitudes calculated from all New Jersey boreholes were based on new porosity-depth relationships estimated from New Jersey Coastal Plain electric logs. In most cases, amplitudes and duration of sea level were comparable when sequences were represented at multiple borehole sites, suggesting that the resultant curves were an approximation of regional sea level. Sea-level amplitudes as great as 50 m were required by third-order Cretaceous sequences. Most amplitudes were probably closer to 20 to 40 m. Third-order (0.5-3 m.y.) sea-level changes of Paleocene and younger sequences were generally less than 30 m and were superimposed on a long-term (= 100 m.y. duration) sea-level fall from a maximum early Eocene value of approximately 100 to 140 m.

Sea level and deep-sea temperature reconstructions suggest quasi-stable states and critical transitions over the past 40 million years

“…The  SL record of de Boer (4) indicates about −45 m of sea level change across the EOT (accounting for different pre-EOT values in Fig. 4A), similar to −30-to −50-m estimates of relative sea level fall from New Jersey Coastal Plain backstripping analysis (65); both are closer to our estimate than to the −70-to −80-m estimates. This EOT  SL discrepancy must be considered together with the difference between Mg/ Ca-based ~2.5°C EOT cooling (66) and our inferred ~3.5°C cooling (Fig.…”

Back To Basics of Sequence Stratigraphy: Early Miocene and Mid-cretaceous Examples from the New Jersey Paleoshelf

“…This south-to-north ''zipper'' onset of seafloor spreading is associated with a diachronous postrift unconformity that separates active ''rift-stage'' deposits from more passive-margin ''drift-stage'' deposits that accumulated in an everwidening and deepening basin open to the ocean. Post-rift history was generally dominated by passive simple thermoflexural subsidence and loading (Steckler and Watts 1978;Grow and Sheridan 1988;Kominz et al 1998Kominz et al , 2002. Subsidence began offshore in the Early Jurassic and progressively moved onshore from the Late Jurassic to the Early Cretaceous (ca.…”

Geometrical Breakdown Approach to interpretation of depositional sequences

“…More than 30 seismic profiles and dozens of offshore boreholes, such as the IODP Expedition 313 and the New Jersey Sea-Level Transect, have greatly improved the resolution of the sequence stratigraphic model for the margin (e.g., Greenlee et al, 1992;Kominz et al, 2002;Miller et al, 2013;Mountain et al, 1996Mountain et al, , 2007Poag and Watts, 1987). Nearly continuous records from the Oligocene to middle Miocene form an excellent repository for evaluating chronostratigraphic and paleoenvironmental constraints (Steckler et al, 1999;Kominz et al, 2002;Browning et al, 2013;Katz et al, 2013;McCarthy et al, 2013).…”

“…More than 30 seismic profiles and dozens of offshore boreholes, such as the IODP Expedition 313 and the New Jersey Sea-Level Transect, have greatly improved the resolution of the sequence stratigraphic model for the margin (e.g., Greenlee et al, 1992;Kominz et al, 2002;Miller et al, 2013;Mountain et al, 1996Mountain et al, , 2007Poag and Watts, 1987). Nearly continuous records from the Oligocene to middle Miocene form an excellent repository for evaluating chronostratigraphic and paleoenvironmental constraints (Steckler et al, 1999;Kominz et al, 2002;Browning et al, 2013;Katz et al, 2013;McCarthy et al, 2013). Previous studies of the New Jersey rifted margin showed that, since Oligocene times, eustasy, subsidence, sediment supply, and isostasy have contributed to the shoreline movement, with eustatic forcing being predominant (Grow and Sheridan, 1988;Mountain et al, 2010;McCarthy et al, 2013;Miller et al, 2014 Research Paper sequences) has revealed numerous records of sea-level cycles (Greenlee et al, 1992;Miller and Mountain, 1994;Steckler et al, 1999;Miller et al, 2014).…”