Netherlands Journal of Geosciences / Geologie en Mijnbouw 81 (2): 201-209 (2002) The Pleistocene drainage pattern in the Lower Rhine Basin W. Boenigk Geologisches Institut, Abt. Quartargeologie, Universitat zu Koln, Ztilpicher Strasse 49a, 50674 Koln, Germany; e-mail: [email protected] Manuscript received: August 2000; accepted: January 2002 PI Abstract During die Pleistocene the drainage pattern in the Lower Rhine Basin changed twice, from a flooding of the whole basin by the river Rhine from SW to NE to an influence restricted to the NE only. The first dominance of the river Rhine is documented from the Reuverian to theTiglian, the second one in the Cromerian. In between this time, the Meuse River drained the central Lower Rhine Basin in NE direction. For the sediments of that river, the term 'Holzweiler Formation' is introduced. Since the Late Cromerian, the influence of the Rhine is again restricted to the NE of the Lower Rhine Basin. The central part of the basin is drained by small local rivers. Key words: Drainage, heavy minerals, lithostratigraphy, Lower Rhine Basin, Pleistocene Introduction the Lower Rhine Basin. Four different pebble assem­ blages can be determined (Fig. 2): The Rhine River drains the Lower Rhine Basin along 1. Tertiary gravel with its source area in the Rhenish the eastern part of the uplifted Koln Block more or Massif (Rh-M) only: This assemblage is charac­ less parallel to the main tectonic faults (Fig. l).The terised by more than 90 % of quartz pebbles in the Meuse River drains this basin only in the NW and coarse pebble fraction. The residual consists of flows perpendicularly to the main faults. quartzites only. Sedimentological features as well as petrographic 2. Tertiary gravel from an extended source area fur­ compositions of the sediments were used to recon­ ther to the south: the Kieseloolite (KOO) gravel. struct the evolution of the Quaternary drainage pat­ Typically, the quartz content ranges from 80 to tern in the Lower Rhine Basin. Some new outcrops in 90%. Additionally there occur some minor con­ the SW - open cast mine Inden - and in the NE - tent of quartzite and other siliceous pebbles. The open cast mine Garzweiler - allow to reconstruct the source areas of KOO pebbles are the Jurassic drainage pattern more detailed than previously done rocks in eastern France indicating Tertiary fluvial by Breddin (1955), Schnutgen (1974), Boenigk activity of the pre-Rhine system. (1978a, b) and Priifert (1994). 3. Pleistocene Rhine gravel (Rhine): The composi­ tion of this gravel is characterised by a remarkable Observation decrease in quartz content compared with the above mentioned Tertiary gravel assemblages. The Pebble countings and heavy mineral analyses are ex­ percentage of quartz decreases from about 65% to cellent stratigraphic tools in Pleistocene sediments of less than 20% from the bottom to the top. The Netherlands Journal of Geosciences / Geologie en Mijnbouw 81 (2)2002 201 Downloaded from https://www.cambridge.org/core. IP address: 170.106.33.22, on 02 Oct 2021 at 06:56:30, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0016774600022447 Venlo Tegelen •" Upper Middle Low iiSFi pre-Quaternary Terraces Terraces Terraces Fig. 1. Lower Rhine Basin with Pleistocene terraces and Holocene drainage pattern of the Rhine and Meuse rivers. J-H = Jackrather Horst, B-E-H = Briiggen-Erkelenzer Horst. presence of radiolarites in the pebble spectra gives pebbles from Cretaceous rocks is typical for these evidence of the Alps as source area. deposits and rocks. Additionally, Revin Quartzite Volcanic components are typical for Middle - Cambrian in age - can be taken as typical pebble Pleistocene deposits, indicating volcanic activity in for these deposits. the Eifel area during the past 700.000 years. Meuse gravel (Meuse) in the central Lower Rhine Six different spectra of heavy minerals can be distin­ Basin: Quartzite pebbles predominate in this grav­ guished in the Lower Rhine Basin (Fig. 2). el. The occurrence of up to 20% of angular flint 1. Material from the Rhenish Massif (Rh-M) pro- 202 Netherlands Journal of Geosciences / Geologie en Mijnbouw 81 (2) 2002 Downloaded from https://www.cambridge.org/core. IP address: 170.106.33.22, on 02 Oct 2021 at 06:56:30, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0016774600022447 Pe b b 1 e s Rh-M KOO Rhine Meuse r100% Mill Qut Qut •80 Qut Q jt -60 Qu Qu -F- •40 Qu u -20 Qu -0 Heavy minerals Rh-M marine KOO Meuse 100% =*>= ^§L Met, Met, • + 80 • WW .St 60 stab stab stab stab 40 20 0 early - late Tertiary Pleistocene Fig 2. Typical pebble and heavy mineral associations of Tertiary and Quaternary sediments in the Lower Rhine basin. Rh-M = Rhenish Mas- siv; KOO = Kieseloolite Formation; stab = stable; Met = Kyanite, Sillimanite, Andalusite; St = Staurolite; Ho = Hornblende; E = Epidote group and Alterites; Gr = Garnet; vole = volcanic; Qu = Quartz; Qut = Quartzite; F = Flint. vides extremely stable minerals only: zircon, tour­ The younger Rhine sediments, younger than maline and rutile are dominating. When there are Cromerian, are characterised by volcanic heavy rocks and/or sediment from the Buntsandstein minerals (Rhine) from the East Eifel volcanic formation, the tourmaline content increases. field. Tertiary marine (marine) sediments are charac­ Meuse sediments (Meuse) from the central part of terised by extremely stable heavy minerals and a the Lower Rhine Basin can be characterised by high percentage of metamorphic minerals. Stauro­ stable heavy minerals. The association is very simi­ lite, kyanite, sillimanite and andalusite are abun­ lar to the mineral content of the Tertiary marine dant. Staurolite and kyanite dominate in this spec­ sands (marine) in the Lower Rhine Basin. Stauro­ trum. lite and kyanite are common; sillimanite and an­ Pliocene Kieseloolite (KOO) sediments are char­ dalusite are rather additional. A typical green- acterised by a stable heavy mineral spectrum with brown-yellowish hornblende ('Vogues Horn­ high content of staurolite. blende') occurs, different to the green or brown 4. The Pleistocene sediments of the river Rhine one of the Eifel area. (Rhine) differ completely in their heavy mineral In the Lower Rhine Basin, pebble and heavy min­ association and in their carbonate, mica and eral frequencies allow to subdivide the Pliocene feldspar content from the Tertiary sediments. In and Pleistocene sediments into five main units, the lower part of the Pleistocene sediment record, whereas the pebble and heavy mineral spectra the most frequent heavy minerals are garnet, epi­ with their source exclusively in the Rhenish Massif dote and green hornblende. In the middle part of (Rh-M) are not included. These sediments are the record, Cromerian in age, epidote dominates known from the Paleogene only. in most cases. The section studied in this article shows the fol- Netherlands Journal of Geosciences / Geologie en Mijnbouw 81(2) 2002 203 Downloaded from https://www.cambridge.org/core. IP address: 170.106.33.22, on 02 Oct 2021 at 06:56:30, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0016774600022447 lowing subdivisions from the bottom to the top Formation. Meuse sediments occur in the Eijsden (Tab.l): Formation, (Tab.l) (Ebbing et al., 1999). The Kieseloolite (KOO) Formation (Fliegel & In the central part of the Lower Rhine Basin, Stoller, 1913): Meuse and Rhine/Meuse mixed sediments are These Pliocene sediments with KOO pebble and quite characteristic and represent a very good key heavy mineral spectrum are equivalent to the KOO horizon for subdividing the Lower to Middle terraces to the Middle Rhine area (Kaiser, 1961). Pleistocene deposits in this area. Klostermann The Tegelen Formation (Zagwijn, 1960): (1992) does not mention these sediments in the In the area of the Erft-Block and the Venlo-Graben stratigraphic column. With respect to their impor­ these sediments consist of Pleistocene Rhine de­ tance for the understanding of the drainage histo­ posits with a quartz pebble content higher than 55 ry in the Lower Rhine Basin they are defined as % and with a heavy mineral spectrum with garnet, Holzweiler Formation. epidote and green hornblende. These sediments The type area is located in the northern part of the can be treated as equivalent to parts of the Early Erft basin, north of a line from Hambach to Bed- Pleistocene terraces in the Middle Rhine area burg, including the Jackrather Horst and the (Hoselmann, 1994). southern part of the Venlo Graben between the The Holzweiler Formation: Jackrather Horst and Monchengladbach (Fig. 1). The Tegelen Formation is covered by sediments of The Holzweiler Formation consists of Meuse sedi­ the Meuse River. They occur mainly in the central ments - coarse gravel and sand with clay lenses - part of the Lower Rhine Basin. The pebble con­ underlain by Rhine sediments of the Tegelen For­ tent and the heavy mineral association are very mation and overlain by Rhine sediments of the typical as Fig. 2 (Meuse) shows. These sediments Upper Terrace Sequence i.e. 'Hauptterrassen- are correlated with parts of the Early Pleistocene Folge' after Burghardt & Brunnacker (1974) and terraces of the Middle Rhine area and with the Schniitgen (1974). Kedichem Formation (Boenigk, 1978b) as de­ The following sections may serve as type-sections: scribed in the Dutch stratigraphy (Zagwijn, 1957; Gravel pit Holzweiler: Geological map, sheet 4904 Doppert et al, 1975). Titz, R 27 375, H 60 250 described by: Schniitgen In recent papers (Ebbing et al., 1999;Weerts et al., (1974) section Nr. 94, and Boenigk (1978b), sec­ 2000) the term 'Kedichem Formation' is no tion 16, between 70 - 76,5 m ASL and open cast longer used.