Utrecht University | Dept. Physical Geography | www.geo.uu.nl/fg/palaeogeography
New results from the Upper Rhine-Meuse delta
G. Erkens, M.J.P. Gouw, K.M. Cohen, W.Z. Hoek, E. Stouthamer New data
6°0’E 6°0’E
5°30’E 5°30’E
52°0’N51°40’N
140,000
140,000
160,000
160,000
180,000
180,000
200,000
200,000
220,000
220,000 420,000440,000460,000
800 - 0 BP Embankment 800 - 1500 2000 - 1500 2500 - 2000 3000 - 2500
3500 - 3000 4000 - 3500 4500 - 4000 5000 - 4500 5500 - 5000 6000 - 5500
6500 - 6000 7000 - 6500 7500 - 7000 8000 - 7500 8500 - 8000
Rivers, canals and lakes Cross sections
A-E Gouw and Erkens NJG 2007 Betuwelijn section, B&S 2001
AHN (c) RWS-AGI 2005 High : 20 Low : -10
0 10 20 30 40
km E’
D’
C’ B’ A’
E
D
C B
A
Fluvial channel belt age (cal yr BP) Miscellaneous Background
G E R M A N Y Den Bosch
Nijmegen Utrecht
Arnhem Ou
de IJssel
Rhine
Niers Meuse
IJssel
Waal Linge
Meuse Utr. Ve
cht
1000 AD
1 BC/AD
1000 BC
Embanked rivers Former rivers River floodbasin
Erkens & Cohen (2009) Erkens & Cohen (2009)
Roman-age arrival of Bronze age sediment
The 2001 Berendsen & Stouthamer map of the Rhine-Meuse delta (Fig. 1) is the reference map for channel belt age in the Netherlands.
Research projects over the last decade have added new data. In the eastern Netherlands this comprises:
1. Five SN cross-sections including time lines (Gouw & Erkens, 2007 NJG)
2. History of sediment delivery to the Holocene delta (PhD thesis Erkens) 3. Mapping and dating Rhine deposition in
the Gelderse IJssel valley (Cohen) 4. Late Glacial/Holocene landscape change
in the Oude IJssel- and Niers-valley (Hoek)
Upstream of section A-A in Fig. 1 the delta doubled in size between 1000 BC and 1000 AD. Analysis of stored amounts of fine-clastic deposits reveals the delta to receive increased amounts fine of sediment, especially since Roman times (last 2000 years; Fig. 2).
This is due to deforestation in Germany, which was widespread during Bronze and Iron age times. Along the Rhine trunk valley (e.g. the Upper Rhine Graben) the sedimentation increase is also registered but started
~1000 years earlier - indicating a lag time in sediment arrival.
Most of the excess sediment was trapped in the upper delta. Around 500 AD this allowed for avulsion of the Gelderse IJssel, which greatly expanded the area of Rhine floodbasin deposition and changed flooding frequencies in the lower delta (Fig. 3).
Fig. 1 Holocene Rhine-Meuse delta (Berendsen & Stouthamer 2001, updated)
Fig. 3 Palaeogeography 1000 BC - 1000 AD
Fig. 2 Holocene delta growth and deposition history (Erkens & Cohen, in prep.)
0 500 1000 1500 3000 3500
a) areal growth b) deposited fine-clastics
2000 2500 Legend
Lower delta G-G H-H
F-F
Oude Rijn
Central delta Utr. Vecht D-D
E-E
Upper delta B-B
C-C
A-A
Gld.IJssel km2
800-0 (Emb.) 1500- 800 2000- 1500 2500- 2000 3000- 2500 3500- 3000 4000- 3500 4500- 4000 5000- 4500 5500- 5000 6000- 5500 6500- 6000 7000- 6500 7500- 7000 8000- 7500 8500- 8000 9000- 8500
9000- 8500
8500- 8000
8000- 7500
7500- 7000
7000- 6500
6500- 6000
6000- 5500
5500- 5000
5000- 4500
4500- 4000
4000- 3500
3500- 3000
3000- 2500
2500- 2000
2000- 1500
1500- 800
800-0 (Emb.)
Mton/yr
0 0.5 1.0 1.5 2.0 2.5 Reduction in trapped volumes 3.0
due to reduced trapping efficiency and decreasing delivery
Increase in trapped volumes under stable trapping efficiency:
strongly increased delivery 19th century: 4.2 Mton/yr
modern: 2.5-3.4 Mton/yr
reconstructed suspended load Lower Rhine
