Abstract: 

Depositional-dip-oriented transects through coastal-plain to nearshore marine domains are essential elements of generic sequence stratigraphic models for continental-margin successions. Many questions remain about the validity of these models, however, because well-constrained outcrop examples are sparse. Presented herein is the first detailed study of a 30-km-long, almost continuously exposed, depositional-dip transect through nonmarine and marine facies of the fluvio-deltaic Ferron Sandstone. This transect is connected to the southern end of a previously documented, 67-km-long, depositional-strike-oriented section. Excellent exposure reveals relationships among facies, stacking patterns, and bounding surfaces across three orders of sequences and various shoreline trajectories. Deposits of sequences are dominated by falling-stage systems tracts, suggesting a regime dominated by long, gradual relative falls in sea level punctuated by shorter relative rises. Widespread fluvial downcutting is generally absent. Distributary-channel sandstones pass down dip into broadly contemporaneous shoreface and delta-front sandstones. A composite sequence boundary divides the study interval into two composite sequence sets. Sequence sets I–III comprise eastward-dipping, offlapping clinoform sets defining a descending, regressive shoreline trajectory (falling-stage deltas). Sequence sets IV–VI overlie a thin transgressive deposit and consist of progradational to aggradational clinoform sets (highstand deltas). Key bounding surfaces are similar at all scales of the hierarchy: they are diachronous, cryptic, and pass down depositional dip into conformable surfaces where they are almost impossible to recognize as key surfaces. Differentiation between units and surfaces that develop at different hierarchical levels is possible only by integrating detailed outcrop observations with regional stratigraphic architecture.

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