Preservation of a drowned gravel barrier complex: A landscape evolution study from the north-eastern English Channel

摘要

Landscape response to post-glacial relative sea level during the Quaternary is documented using an integrated dataset of multibeam bathymetry and 2D seismic reflection profiles from the Hastings Bank area in the north-eastern English Channel. Mapping of nine seismic stratigraphic units calibrated to lithological information from multiple vibrocores has enabled the interpretation of fluvial, shoreface, barrier, washover fan, back-barrier and tidal environments of deposition. The interpreted landscape evolution is as follows: (i) fluvial incision of bedrock during sea-level lowstand; (ii) progradation of a shoreline and then development of a barrier complex as sea-level rose; (iii) recycling and breaching of the barrier; (iv) rapid drowning of the barrier complex; (v) landward migration of the shoreline through continued sea-level rise; and (vi) complete abandonment and submarine preservation of the barrier complex during sea-level highstand.