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This paper provides the most-accurate sea-level index points (SLIPs) for the Rhine-Meuse Delta (RMD), The Netherlands, identified amidst a wealth of data accumulated in sixty years of research. Following documented protocols, 106 selected radiocarbon dates from peat beds from transgressed valley floor, upper estuarine and back-barrier lagoonal settings were first listed individually, then screened in ensemble on quantified age-depth position and inshore palaeotidal setting. The database contains 50 SLIPs and 56 upper limiting data points spanning a depth range of −34 to −1.5 m. The dates in the database originate from dedicated sea-level research, which kept surface elevation and sampling depth uncertainty small, and sampling of basal-peat beds was favoured, keeping compaction uncertainties small too. The SLIPs cover an age-range of 8.8–3.0 ka BP and are available from Greater Rotterdam and its near offshore. For upper limiting data points, the coverage extends offshore, tracing the Rhine palaeovalley, and reaches back to 11.5 ka BP. The age-depth data density and spatial concentration of subsets of dates allow to perform Bayesian radiocarbon calibration and to reduce temporal uncertainty by 25% for the average sample (1σ age uncertainty ≈ 75 cal. yr), when depth position and rates of relative sea-level rise (RSLR) are used to assign sequence order. Between 8.0–4.5 ka BP, rates of RSLR gradually decreased from 9 to 1 mm/yr. In the millennium before, rates of RSLR were much higher, on average 10 mm/yr, and marked by a sea-level jump between 8.45–8.2 ka BP. A two-phased nature of this jump starts to be resolved, with local magnitudes of 1.7 ± 0.6 m (1σ, first phase) and 0.2 ± 0.2 m (second phase), corresponding to globally-averaged jumps of 2.5 m ± 0.9 m for the first and 0.3 ± 0.3 m for the second phase. For the pre-9 ka BP period, only offshore upper limiting data points are currently available. Until new offshore data are gathered, trends of RSLR before 9 ka BP can only be estimated, fed with global insights in post-glacial eustasy, regional estimates regarding rates of glacio-isostatic adjustments and tectonic subsidence, and sedimentary geological interpretations of scattered basal-peat presence.

This study presents a detailed reconstruction of the palaeogeography of the Rhine valley (western Netherlands) during the Holocene transgression with systems tracts placed in a precise sea-level context. This approach permits comparison of actual versus conceptual boundaries of the lowstand, transgressive and highstand systems tracts. The inland position of the highstand Rhine river mouth on a wide, low-gradient continental shelf meant that base-level changes were the dominant control on sedimentation for a relatively short period of the last glacial cycle. Systems in such inland positions predominantly record changes in the balance between river discharge and sediment load, and preserve excellent records of climatic changes or other catchment-induced forcing. It is shown here that the transgressive systems tract-part of the coastal prism formed in three stages: (i) the millennium before 8·45 ka bp, when the area was dominated by fluvial environments with extensive wetlands; (ii) the millennium after 8·45 ka, characterized by strong erosion, increasing tidal amplitudes and bay-head delta development; and (iii) the period between 7·5 and 6·3 ka bp when the Rhine avulsed multiple times and the maximum flooding surface formed. The diachroneity of the transgressive surface is strongly suppressed because of a pulse of accelerated sea-level rise at 8·45 ka bp. That event not only had a strong effect on preservation, but has circum-oceanic stratigraphical relevance as it divides the early and middle Holocene parts of coastal successions worldwide. The palaeogeographical reconstruction offers a unique full spatial–temporal view on the coastal and fluvial dynamics of a major river mouth under brief rapid forced transgression. This reconstruction is of relevance for Holocene and ancient transgressive systems worldwide, and for next-century natural coasts that are predicted to experience a 1 m sea-level rise.

This study presents a detailed reconstruction of the palaeogeography of the Rhine valley (western Netherlands) during the Holocene transgression with systems tracts placed in a precise sea-level context. This approach permits comparison of actual versus conceptual boundaries of the lowstand, transgressive and highstand systems tracts. The inland position of the highstand Rhine river mouth on a wide, low-gradient continental shelf meant that base-level changes were the dominant control on sedimentation for a relatively short period of the last glacial cycle. Systems in such inland positions predominantly record changes in the balance between river discharge and sediment load, and preserve excellent records of climatic changes or other catchment-induced forcing. It is shown here that the transgressive systems tract-part of the coastal prism formed in three stages: (i) the millennium before 8·45 ka bp, when the area was dominated by fluvial environments with extensive wetlands; (ii) the millennium after 8·45 ka, characterized by strong erosion, increasing tidal amplitudes and bay-head delta development; and (iii) the period between 7·5 and 6·3 ka bp when the Rhine avulsed multiple times and the maximum flooding surface formed. The diachroneity of the transgressive surface is strongly suppressed because of a pulse of accelerated sea-level rise at 8·45 ka bp. That event not only had a strong effect on preservation, but has circum-oceanic stratigraphical relevance as it divides the early and middle Holocene parts of coastal successions worldwide. The palaeogeographical reconstruction offers a unique full spatial–temporal view on the coastal and fluvial dynamics of a major river mouth under brief rapid forced transgression. This reconstruction is of relevance for Holocene and ancient transgressive systems worldwide, and for next-century natural coasts that are predicted to experience a 1 m sea-level rise.