Abstract We describe sedimentation on the storm-dominated, microtidal, continental shelf and slope of the eastern US passive continental margin between the Hudson and Wilmington canyons. Sediments here recorded sea-level changes over the past 100 myr and provide a classic example of the interplay among eustasy, tectonism and sedimentation. Long-term margin evolution reflects changes in morphology from a Late Cretaceous–Eocene ramp to Oligocene and younger prograding clinothem geometries, a transition found on several other margins. Deltaic systems influenced Cretaceous and Miocene sedimentation, but, in general, the Maastrichtian–Palaeogene shelf was starved of sediment. Pre-Pleistocene sequences follow a repetitive model, with fining- and coarsening-upward successions associated with transgressions and regressions, respectively. Pleistocene–Holocene sequences are generally quite thin (<20 m per sequence) and discontinuous beneath the modern shelf, reflecting starved sedimentation under high rates of eustatic change and low rates of subsidence. However, Pleistocene sequences can attain great thickness (hundreds of metres) beneath the outermost shelf and continental slope. Holocene sedimentation on the inner shelf reflects transgression, decelerating from rates of approximately 3–4 to around 2 mm a −1 from 5 to 2 ka. Modern shelf sedimentation primarily reflects palimpsest sand sheets plastered and reworked into geostrophically controlled nearshore and shelf shore-oblique sand ridges, and does not provide a good analogue for pre-Pleistocene deposition. Supplementary material: References used in the comparison of all dates for New Jersey localities in Figure 3.8 are available at http://www.geolsoc.org.uk/SUP18749 .

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Abstract The E5 transect extends southeastward from the Cumberland Plateau across the Appalachian orogen, the Atlantic Coastal Plain, Continental Shelf and Slope, and the Blake Plateau Basin; it is a transect through the Precambrian-early Paleozoic and Mesozoic-Tertiary continental margins of North America. The transect consists primarily of a 100-km-wide geologic strip map, a cross section, and supporting geophysical data. The cross section is based on surface geology, surface and subsurface data from Coastal Plain and offshore drill holes, shipboard and aeromagnetic data, and gravity and seismic reflection data, including the ADCOH and COCORP southern Appalachians lines. Elements of the map and cross section include: (1) the Appalachian foreland fold-thrust belt and western Blue Ridge Late Proterozoic-Paleozoic continental margin; (2) the eastern Blue Ridge-Chauga belt-Inner Piedmont oceanic-continental fragment terrane; (3) the volcanicplutonic Carolina terrane containing the middle to late Paleozoic high-grade Kiokee belt; and (4) a major geophysical ly defined terrane beneath the Coastal Plain. Three Paleozoic sutures may be present along the section line: the Hayesville thrust, the Inner Piedmont-Carolina terrane boundary (Taconic or Acadian suture?), and an eastern boundary of the Carolina terrane (Alleghanian? suture) in the subsurface beneath the Coastal Plain. The modern continental margin consists of the terrestrial clastics-filled Triassic-Jurassic basins and offshore marine Jurassic- Cretaceous clastic-carbonate bank succession overlain by younger Cretaceous and Tertiary sediments. Above the Late Cretaceous onshore unconformity lie Cenozoic sediments that represent seaward prograding of the shelf-slope, truncated by Miocene to recent wave abrasion and currents.

Abstract DNAG Transect E-5. Part of GSA's DNAG Continent-Ocean Transect Series, this transect contains all or most of the following: free-air gravity and magnetic anomaly profiles, heat flow measurements, geologic cross section with no vertical exaggeration, multi-channel seismic reflection profiles, tectonic kindred cross section with vertical exaggeration, geologic map, stratigraphic diagram, and an index map. All transects are on a scale of 1:500,000.

Abstract High-resolution seismic-reflection profiles and Vibracore information from unpublished and published studies of the U. S. Coastal Plain are used to develop depositional models for valley-fill sequences formed on a passive continental margin. The lower bounding unconformity (SB I) is produced by fluvial incision during sea-level lowstands. Valleys are both shore-parallel controlled by Coastal Plain cuestas and shore-normal. Depressions are cut by both fluvial and tidal erosion. Some small valleys, tidal inlet throats, are infilled with cross-bedded sands, whereas small river channels are likely to be backfilled with mud as the base level changes during a transgression. Intermediate-sized valleys represent deposition in major tributaries to Coastal Plain rivers, and the fill is a fining-upward package generally truncated by a ravinement and overlain with inner shelf sands. Large "drowned-river" valleys are characterized by a sediment sandwich of sand-mud-sand which may contain several marine erosion surfaces and have a high proportion of sand. Subsidence rates of the Atlantic margin are 1–2 mm/yr, topographic relief is <40 m, sediment influx is low, and present shoreline migration rates are 3 m/yr. During transgressions, depth of erosion is estimated at 5–10 m, and thus preservation potential for the lower portion of the valley fill is excellent for the large valleys, good for the intermediate valleys, and poor for the small valleys. Topography is an important factor in valley-fill preservation on passive margins. Depressions created from fluvial or shoreface erosion often provide the only "accommodation space" on continental shelves of passive margins that will shield TST deposits from erosion and ensure preservation of the geological record.