The stratigraphic record of sea-level change and storms during the last 2000 years: Romney Marsh, southeast England

Abstract

Abstract The record of late-Holocene sea-level change and coastal evolution in the Romney Marsh region is either absent or made complex by the range of environmental variables which influence sedimentation in both drift-aligned barrier and barrier estuary settings. A multidisciplinary approach (stratigraphy, diatoms and mineral magnetism) was employed in the study of sediments from the area of Denge Marsh with the aim of establishing the record of sea-level change for the last 2000 years, and to distinguish sedimentary records which are the result of sea-level change or storms. A grid-based stratigraphic framework was used to identify the morphology of the buried gravel ridges and the marsh stratigraphy. A tripartite fining-upward sequence was identified and investigated to determine the nature of sediment processing, deposition and provenance. An early phase of tidal flat sedimentation was dominated by a high terrigenous sediment influx. This was followed by intertidal mudflat deposition in a barrier estuary as the gravel foreland prograded eastward. It is likely that this phase of marsh accretion came to an end in the 8th century AD. The final phase of barrier estuary deposition would appear to be the result of storm surges which inundated the marsh during the 13th century AD. Comparison of stratigraphic contact altitudes, as approximate indicators of past MHWS level, with the present day MHWS provides only equivocal data on late-Holocene sea-level change.