We developed a sequence stratigraphic framework for the (Barremian to lower Cenomanian) fluvial-deltaic (primarily delta plain) Potomac Formation in the Medford, New Jersey, Fort Mott, New Jersey, and Summit Marina, Delaware coreholes. Previous studies have correlated distinctive lithologic units with attendant pollen zones and identified tentative sequence boundaries between lithologic units I (Barremian to lower Aptian, pollen Zone I), II (Aptian to lowermost Cenomanian, pollen Zone II), and III (lower Cenomanian, pollen Zone III) at all three sites. Here, we further subdivide these units into packages known as fluvial aggradation cycles (FACs). An analysis of FAC stacking patterns reveals potential sequence boundaries and systems tracts. FACs indicate that major lithologic unit boundaries are also sequence boundaries, indicate tentative higher-order sequence boundaries, and provide potential additional correlative surfaces among Potomac Formation sites. Our study demonstrates the applicability of the FAC method to identify stacking patterns and sequence stratigraphic surfaces in fluvial-deltaic deposits and demonstrates that FACs are excellent tools to decipher the difficult-to-correlate surfaces.
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