Estimating postglacial coastal sediment budgets is difficult as erosion has removed the landscape drowned by marine transgression and coastal positions through time are rarely known. In the Natural Environment Research Council (NERC)–funded Land Ocean Interaction Study, a model was built, based on detailed characterization of onshore-offshore bathymetric profiles (created by Holocene wave-base migration). Modeling of the pre-Holocene western North Sea land surface (west of 1°E and south of 54°N) and sea-level curves allow determination of the likely position of wave base and coast at any time during the late Holocene. The volumes of materials eroded from cliffs, wave action on the shoreface, and tidal scour associated with erosion of pits (e.g., Inner Silver Pit) from different coastal areas have been estimated. The average annual contribution of sediment per meter length of coast is higher than some recent erosion rates would suggest, but appears consistent with the volumetric difference between the modeled end-Pleistocene surface and the present topographic-bathymetric surface. With other models, outputs would suggest that less than 5% of the Humber Holocene is likely to be of fluvial origin—a percentage corroborated by detailed geochemical and mineralogical provenance studies of the estuarine fill. The model suggests that more sediment has been released from the shoreface than from cliffs per unit length of coastline throughout the Holocene; this is an important finding for coastal managers, as this pattern is likely to continue and because the shore-face cannot be effectively protected from erosion.

Abstract The Holocene sedimentary facies of the Fenland are described using a lithological database and new cores recovered as part of the Land–Ocean Interaction Study. Landward, the Holocene sequence is dominated by mud facies with intercalated peat layers, whereas the seaward areas are sand-dominated. The sedimentological characteristics of the mud facies are homogeneous and are similar for the whole sequence. Glacial deposits located north of The Wash are thought to be the main sediment sources. The sand facies generally fines upwards and the chemistry reflects this change. However, elemental ratios show only slight variations between the two facies implying a general constancy of sediment provenance. The evolution of the Fenland has been dominated by three main events. Firstly, the initial post-glacial transgression, which started c . 7850 cal. BP . Secondly, the sedimentary infilling of the embayment with rising sea-level; deposition of intertidal clastic sediments alternating with peat accumulation. Thirdly, renewed expansion of tidal flat areas between c . 2750 and 1500 cal. BP forming the final clastic fill.