Holocene palaeogeographic development of the Rhine-Meuse delta
- Figure 2 Core taken with the Van der Staay suction corer: sand (right) on clay (left).
- Figure 3 Taking samples with the gauge.
- Figure 4 Gerard Ouwerkerk taking a C-14 sample with the Dachnowski-sampler.
The Holocene palaeogeographic development of the Rhine-Meuse delta was summarized by Berendsen & Stouthamer (2000, 2001). These studies are based upon approximately 40 years of mapping by undergraduate students at the Department of Physical Geography during the so-called 'Laaglandgenese field course'. This has resulted in a database, containing over 200,000 lithological borehole descriptions. A geological-geomorphological map of the ages of the Holocene channel belts (scale 1:100,000) was published, together with palaeogeographic maps at 500 yr time intervals (Berendsen & Stouthamer, 2001). Figure 1 is a simplified version of the map, with a digital elevation model in the background.
- Figure 1. Geological map of the Rhine-Meuse delta (Berendsen & Stouthamer 2001), publication scale 1 : 100.000, showing all the channel belts that were formed during the Holocene from 7000 yr BP to the present. Legend: red = young, green = old. Color shades represent time steps of 500 years. Enlarge
Methods and data used for the reconstruction of the palaeogeographic development:
- 200,000 lithological borehole descriptions (Figure 2 and 3),
- 1200 14C dates (Figure 4 and 5),
- 45,000 archaeological artifacts (Figure 6),
- gradient lines of 200 channel belts (Figure 7).
Lithological borehole descriptions were made for every 10 cm of the core length, and include lithology, organic content, plant remains, color, redox status, gravel and sand size, calcium carbonate content, oxydized iron content, groundwater, samples taken, vegetation horizons, stratigraphy, and other characteristics.
- Figure 5 C-14 samples are described and wrapped in aluminum foil and then sealed in plastic.
- Figure 6 Flint arrowpoint of Neolithic age.
- Figure 7 Construction of the gradient line of a channel belt (Berendsen 1982). Enlarge.
Radiocarbon dates are generally taken at the transition from clay to peat or vice versa, and date the end or the beginning of river activity respectively. In addition, many radiocarbon samples were taken from residual channels. They date the end of sedimentation of the channel belt. All our samples were dated by the Centre for Isotope Research, Groningen, and the Robert J. van de Graaff-laboratory in Utrecht.
Archaeological data were obtained from the State Service for Archeological Research (ROB). They were useful for dating channel belts, especially in those areas where peat is absent.
Gradient lines were made of the top of the channel belt sandbody (Figure 7). These gradient lines roughly coincide with the bankfull level of the former river system. If several gradient lines are plotted in one diagram, younger channel belts plot higher than older channel belts (provided that the channel belts are located downstream of the so-called terrace intersection). Hence the gradient lines not only give the direction of the former river flow, but also allow relative dating. Because old channel belts have usually been dissected by younger channel belts, the gradient lines are helpful in reconstructing which channel belts fragments were originally connected. In general, the gradient of channel belts decreased during the Holocene, as a result of relative sea level rise.
Data were stored in a GIS database that enables generation of palaeogeographical maps for any moment during the Holocene. The time resolution of the palaeogeographic reconstruction is approximately 200 years (Berendsen & Stouthamer 2000). Maps have been made for 500 yr intervals. These maps and a legend are available below.
- 10000 years BP
- 7000 years BP
- 6500 years BP
- 6000 years BP
- 5500 years BP
- 5000 years BP
- 4500 years BP
- 4000 years BP
- 3500 years BP
- 3000 years BP
- 2500 years BP
- 2000 years BP
- 1500 years BP
- 1000 years BP
- 500 years BP
- Simplified legend for the palaeogeographic maps (Berendsen & Stouthamer 2001). Enlarge for an extended version.
The book by Berendsen & Stouthamer (2001) contains printed versions of the geological-geomorphological map, scale 1:100,000, as well as the palaeogeographic maps, showing the Holocene evolution of the Rhine-Meuse delta in 500-year time steps.
In addition, the book includes a CD-ROM, containing:
- the description and age of all Holocene channel belts in the Rhine-Meuse delta (updated January 2006). Download as pdf (1.4 MB).
- a table with approximately 1500 14C dates (updated September 26, 2006). Download as pdf (1056 KB).
- extensive references
- the text and all the figures in the book (in color)
- the maps, and cross sections
- animations, movies, PowerPoint presentations and more.
Some of the data has been updated since the book was published. The data as originally published by Berendsen & Stouthamer (2001) is still available from the SEPM Data Archive.
Analyses of the palaeogeographic evolution of the Rhine-Meuse delta show, that avulsion (the shifting of a river course to a new location on the floodplain) was an important process (Stouthamer 2001), resulting in frequent shifts of areas of clastic sedimentation (Figure 8). Avulsion generally starts with the formation of a crevasse splay, originating from a breach in a natural levee (Figure 8). If the crevasse-forming channel obtains a gradient advantage, the crevasse channel may enlarge and eventually take over the entire discharge of the trunk channel. In that case, a new channel belt is formed in a different location on the floodplain. It appears that this process can happen suddenly (within decades to a few centuries), but in other cases it may take thousands of years. If the avulsion occurs within 200 years, it is called instantaneous avulsion, if it takes longer, it is called gradual avulsion. For more information: see the avulsions section.
Factors influencing the Holocene paleogeographic evolution
The palaeogeographic evolution of the Rhine-Meuse delta is governed by complex interactions among several factors. These are:
- Figure 9 Braided pattern of the Slims River, Kluane National Park, Yukon, Canada (picture by H.J.A. Berendsen).
- Figure 10 Late-Weichselian valley of the Rhine and Meuse in the Netherlands (Berendsen & Stouthamer 2001)
- Location and shape of the Late Weichselian palaeovalley. During the Saalian and Weichselian a valley was formed by the then braided Rhine-Meuse system (Figure 9). The valley is bordered by Saalien ice-pushed ridges in the north and Weichselian coversand in the south (Figure 10).
- Sea-level rise, which resulted in back-filling of the palaeovalley. The influence of Holocene sea-level rise led to a rise of the groundwater table (Figure 11), which caused peat formation. Groundwater gradient lines roughly reflect the gradients of channel belts at different times during the Holocene. The crossing of a gradient line with the Pleistocene substratum roughly coincides with the location of the terrace intersection between Holocene and Late Weichselian fluvial deposits. This implies that this terrace intersection shifted upstream during the Holocene, in connection with sea-level rise (Figure 12).
- Figure 11 Rise of the groundwater table during the Holocene. After Van Dijk et al. 1992).
- Peat formation, which was most extensive in the western part of the back-barrier area especially between 4000 and 3000 14C yr BP (Figure 13). This more or less fixed the river pattern at that time, because the wood peat is not easily erodible. In combination with decreasing gradients (as a result of sea-level rise), causing low stream power, this resulted in few avulsions in the westernmost part of the delta.
- Neotectonics. Differential tectonic movements of the Peel Horst and Roer Valley Graben seem to have influenced river behaviour (formation of an asymmetrical meander belt (Figure 14), location of avulsion nodes), especially from 4500 - 2800 14C yr BP when the rate of sea-level rise had decreased. After 2800 14C yr BP sea-level rise further decreased, and tectonic influence still may have influenced avulsions, but from then on other factors became dominant. Gradient lines of the top of the channel belt sands (GTS lines), especially Late Weichselian terrace deposits, are deformed where these channel belts cross the Peel Horst (Figure 15).
- Figure 15 Deformation of gradient lines as a result of tectonic movements (Berendsen & Stouthamer 2001).
- Increased discharge, sediment load and/or within-channel sedimentation. After 2800 14C yr BP, river meanders of Rhine distributaries as well as the single channel of the Meuse show remarkable increases in wavelength (Figure 16), interpreted as a result of increased bankfull discharge and sediment load. Increased discharge may initially have been caused by higher precipitation. After 2000 14C yr BP both discharge and sediment load seem to have increased as a result of human influence. Alternatively, decreasing gradients (as a result of sea-level rise) may have caused increased within-channel sedimentation and channel widening, which would also lead to increased meander wavelenghts.
- Figure 16 Increase of meander lenghth of channels between 2000 and 1000 yr BP (Berendsen & Stouthamer 2001).
- Composition of the river banks. Meandering river channels tend to adhere to the sandy margins of the Late Weichselian palaeovalley, and high channel sinuosity is found in areas where river banks consisted of sand (Figure 17).
- Figure 17 High-sinuosity channels occur where river banks consist of easily erodible sands (Berendsen & Stouthamer 2001).
- Marine ingressions, e.g. the 1421 AD St. Elizabeth's flood caused large-scale erosion in the southwestern part of the fluvial deltaic plain (the Meuse estuary). This shortened river courses debauching into the Meuse estuary, leading to an increased gradient. These channels hence grew larger, resulting in avulsion of the main branches of the Rhine to the Meuse estuary (Figure 18), and abandonment of the former main course of the Rhine (known as the Old Rhine).
- Figure 18 Shift of the main drainage from the Old Rhine mouth to the Meuse estuary (Berendsen & Stouthamer 2001).
Human influence. Since approximately 1100 AD human influence dominated the palaeogeographic evolution. Rivers were embanked and dredged, meanders were cut off, and for the Meuse a new distributary canal (the Bergsche Maas) was dug in 1904 AD (Figure 19). Discharge distribution over the various channels is nowadays strictly controlled.
- Figure 19 In 1904 a new channel was dug for the Maas straight to the tidal estuary of the Amer-Haringvliet (Berendsen 1986).
- Berendsen, H.J.A. & E. Stouthamer (2000), Late Weichselian and Holocene palaeogeography of the Rhine-Meuse delta (The Netherlands). Palaeogeography, Palaeoclimatology, Palaeoecology 161 (3/4), p. 311-335.
- Berendsen, H.J.A. & E. Stouthamer (2001), Palaeogeographic development of the Rhine-Meuse delta. Assen: Van Gorcum, 270 pp.
- Berendsen, H.J.A. & E. Stouthamer (2002), Palaeogeographic evolution and avulsion history of the Holocene Rhine-Meuse delta, The Netherlands. Netherlands Journal of Geosciences/Geologie en Mijnbouw 81 (1), pp. 97-112
- Stouthamer, E. & H.J.A. Berendsen (2000), Factors controlling the Holocene avulsion history of the Rhine-Meuse delta (The Netherlands). Journal of Sedimentary Research 70 (5), p. 1051-1064.
- Stouthamer, E. (2001), Holocene avulsions in the Rhine-Meuse delta, The Netherlands. Netherlands Geographical Studies 283, 211 p.
- Van Dijk, G.J., H.J.A. Berendsen & W. Roeleveld (1991), Holocene water level changes in the Rhine-Meuse delta (The Netherlands), and implications for sea level reconstruction. Geologie en Mijnbouw 70, pp. 311 - 326.