Molluscan aminostratigraphy of the US Mid-Atlantic Quaternary coastal system: Implications for onshore-offshore correlation, paleochannel and barrier island evolution, and local late Quaternary sea-level history

摘要: Abstract The Quaternary record of the US Mid-Atlantic coastal system includes onshore emergent late Pleistocene shoreline deposits, offshore inner shelf and barrier island units, paleovalleys formed during multiple glacial stage sea-level lowstands. geochronology this is based on uranium series, radiocarbon, amino acid racemization (AAR), optically stimulated luminescence (OSL) methods. We report over 600 mollusk AAR results from 93 sites between northeastern North Carolina central New Jersey shelf, representing samples both cores or outcrops, sub-barrier cores, transported shells beaches. age estimates are constrained by paired 14C analyses specific associated U-series coral ages sites. data interpreted in context detailed seismic stratigraphy. distribution Pleistocene-age beaches linked to source units. Age mixing a range time-scales (∼1 ka ∼100 ka) identified onshore, beach, collections, often contributing insights into processes forming individual islands. regional aminostratigraphic framework identifies widespread (Marine Isotope Stage 5) aminozone, with isolated records middle early deposition. provide for timing formation three major paleochannels that underlie Delmarva Peninsula: Persimmon Point paleochannel ≥800 ka; Exmore ∼400–500 (MIS 12); Eastville paleochannel > 125 6). demonstrate value synthesizing abundant chronologic across various environments, integrating distinct geologic studies. elevations units important current hypotheses about relative history crustal dynamics region, which was likely influenced Laurentide ice sheet, margin just ∼400 km north.