BACK TO BASICS OF SEQUENCE STRATIGRAPHY: EARLY MIOCENE AND MID-CRETACEOUS EXAMPLES FROM THE NEW JERSEY PALEOSHELF

Many sequence stratigraphic approaches have used relative sea-level curves to recognize depositional sequences, key stratal surfaces, and systems tracts, leading to contradictory interpretations. Here, we urge following basic sequence stratigraphic principles independent of sea-level curves using seismic, log, facies successions, stacking patterns, and chronostratigraphic data to recognize sequence boundaries, other stratal surfaces, parasequences, and systems tracts. We provide examples from the New Jersey siliciclastic paleoshelf from the: 1) Early Miocene using academic-based chronostratigraphic, seismic, core, downhole and core log data, and 2) mid-Cretaceous using commercial well log, seismic, and biostratigraphic data. We use classic criteria to identify sequence boundaries on seismic profiles by reflection terminations (onlap, downlap, erosional truncation, and toplap), in cores by surfaces of erosion associated with hiatuses detected using biostratigraphy and Sr-isotope stratigraphy and change in stacking patterns, and in logs by changes in stacking patterns. Maximum Flooding Surfaces (MFS) are major seismic downlap surfaces associated with a change from retrogradational to progradational parasequence stacking patterns. Systems tracts are identified by their bounding surfaces and fining/deepening and coarsening/shallowing upward trends in cores and well log stacking patterns. Our Miocene examples of sequences m5.4 (17.7-16.1 Ma) and m5.8 (20.1-19.2 Ma) illustrate how basic sequence stratigraphic techniques reveal composite sequences within of higher-order (Myr scale) sequences. Our mid-Cretaceous example from the New Jersey shelf provides a paleoshelf transect spanning the Great Stone Dome to the outer continental shelf to identify parasequences, sequences, and systems tracts. This sequence stratigraphic framework provides insights into Myr scale coeval depositional environments across the paleoshelf and reservoir continuity, and highlights the application of basic sequence stratigraphic criteria to reservoir-scale evaluation, not only for oil and gas resources, but also for carbon storage. Supported by DOE DE-FE0026087 (Mid-Atlantic U.S. Offshore Carbon Storage Resource Assessment Project) and DE-FC26-0NT42589 (MRCSP) to Rutgers managed by Battelle.