Correlation of English and German Middle Pleistocene Fluvial Sequences Based on Mammalian Biostratigraphy
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Netherlands Journal of Geosciences / Geologie en Mijnbouw 81 (3-4): 357-373 (2002) Correlation of English and German Middle Pleistocene fluvial sequences based on mammalian biostratigraphy D.C. Schreve1* & D.R. Bridgland2 1 Department of Geography, Royal Holloway, University of London, Egham, Surrey, TW20 OEX, UK; e-mail: [email protected]. Corresponding author. 2 Department of Geography, University of Durham, South Road, Durham, DH1 3LE, UK; e-mail: [email protected] Manuscript received: March 2001; accepted: February 2002 Abstract In this paper interglacial mammalian assemblages from key Middle Pleistocene fluvial sites in Germany are compared to Mammal Assemblage-Zones (MAZs) recently established in the post-Anglian/Elsterian sequence of the Lower Thames, UK. It is believed that four separate interglacials are represented by the Lower Thames MAZs, correlated with oxygen isotope stages (OIS) 11, 9, 7 and substage 5e (although the last of these is Late Pleistocene). Nowhere in Germany can a full se quence of these interglacials be identified from mammalian evidence in a single terrace staircase, as is the case in the Lower Thames, although further research on the Wipper terraces at Bilzingsleben may identify such a sequence. It is also possible that the sequence of overlapping fluvial channels in the lignite mine at Schoningen will eventually produce a comparable mammalian story. Excellent correspondence has been recognized between the mammalian assemblages at Steinheim an der Murr and Bilzingsleben II and the Swanscombe MAZ from the Thames. These three sites are attributed to the Hoxnian/Hol- steinian interglacial and are thought to correlate with OIS 11. Close comparison can also be made between the mammalian sequence from the celebrated travertine locality at Weimar-Ehringsdorf and two separate MAZs from Aveley, in the Thames, attributed to separate substages of OIS 7. An equivalent to the Purfleet MAZ of the Thames, which is believed to correlate with OIS 9, has yet to be identified in Germany. Keywords: biostratigraphy, mammals, Middle Pleistocene, river terraces Introduction separate interglacials between the Anglian glaciation and the Last (Ipswichian) Interglacial (Schreve, This paper provides part of the results from a re 2001a). These findings were in complete support of search project, conducted by the authors between the model for the lithostratigraphy and geochronolo- 1997-2000, entitled 'Middle Pleistocene mammalian gy of the Lower Thames terraces, proposed previously biostratigraphy of NW European rivers' (funded by by the second author (Bridgland, 1994, 1995). The the LeverhulmeTrust - see acknowledgements). Prior extension of the project into continental Europe was to the project, the first author had established a based on the selection of key fluvial sites with rich as scheme for the differentiation of interglacials in the semblages of fossil mammals, the examination of British late Middle Pleistocene, based upon the evi those collections and, where possible, liaison with dence from mammalian biostratigraphy (Schreve, continental workers who have researched them. In 1997). The scheme identified a series of distinctive this part of the project, it was found that evidence temperate-climate Mammal Assemblage Zones from sites in Germany was particularly comparable (MAZ) that are believed to correspond with three with the British mammalian biostratigraphical data. Netherlands Journal of Geosciences / Geologie en Mijnbouw 81 (3-4) 2002 357 Downloaded from https://www.cambridge.org/core. IP address: 170.106.202.226, on 27 Sep 2021 at 09:02:24, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0016774600022654 The present paper will outline the Thames mam odic isolation may be an important factor in permit malian biostratigraphical scheme, regarded as a po ting the separation of mammalian assemblages of dif tential template for correlation both within Britain ferent age, since patterns of species presence and ab and more widely in NW Europe, and then examine sence between interglacials should be all the more sig the evidence from selected sites in Germany. nificant, depending on whether individual taxa were able to immigrate before the terrestrial connection The Lower Thames terrace sequence was severed. There is no evidence for the evolution of endemic mammalian species during this time period The terrace stratigraphical model based on the Lower in Britain, although it appears that endemic techno Thames sequence has been described several times logical traits can be seen in the archaeological record previously (Bridgland, 1994, 1995, 2000), informa corresponding with periods of isolation from main tion that is summarized in Table 1 and is illustrated in land Europe (White, 1998; White & Schreve, 2000). Fig. 1. A key aim of the Leverhulme-funded project has It is believed that formation of the Thames terraces therefore been to determine whether signs of insulari was driven by climatic fluctuation during the Quater ty-related differences between contemporaneous fau nary (Bridgland, 1994, 1995, 2000; Bridgland & nas on either side of the English Channel can be de Maddy, 1995), although enabled by progressive uplift tected. throughout the Pleistocene (Maddy, 1997; Maddy & Bridgland, 2000). The climatic fluctuation that has Mammalian assemblages from the Lower Thames terrace driven the timing of fluvial incision and aggradation, sequence thus leading to terrace formation, has also been im portant in controlling the migration of different Sites within the framework of the Lower Thames ter groups of mammals into and out of the NW Euro race sequence were used by Schreve (1997, 2001a) to pean landmass. In Britain, relatively brief periods of erect the testable hypothesis that interglacial sedi past insularity, also climatically controlled, must also ments within each of four separate terraces (Table 1, be taken into account, as they will have temporarily Fig. 1) contained distinctive suites of mammalian fos acted as a barrier to faunal migration. Britain's peri sils. Biostratigraphical analysis of these different Numbers indicate the oxygen isotope stages © to which these deposits have been attributed Interglacial deposits Cold-climate gravels Fig. 1. Idealized transverse section through the Lower Thames terrace sequence, showing the stratigraphical positions of interbedded inter glacial sediments. The most significant characteristics of the mammalian assemblages and their attribution to MAZs are indicated (after Schreve, 2001a; Currant & Jacobi, 2001). Correlations with the oceanic oxygen isotope sequence are suggested. Modified from Schreve (2001a). 358 Netherlands Journal of Geosciences / Geologie en Mijnbouw 81(3-4) 2002 Downloaded from https://www.cambridge.org/core. IP address: 170.106.202.226, on 27 Sep 2021 at 09:02:24, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0016774600022654 Table 1. The Quaternary sequence in the lower reaches of the Thames. Terrace Formation Members: Lower Thames Climate Age 8 lsO Stage Tilbury Tilbury Alluvial Deposits warm Holocene (alluvium) 1 Shepperton Shepperton Gravel cold late Devensian late 2 East Tilbury Marshes East Tilbury Marshes Upper Gravel cold Devensian 5d-2 Trafalgar Square & Peckham Deposits warm Ipswichian 5e East Tilbury Marshes Lower Gravel cold late Saalian late 6 Mucking Mucking Upper Gravel cold late Saalian 6 Aveley Silts and Sands warm intra-Saalian 'Stanton 7 Harcourt Interglacial Bowen et al. (1989) Mucking Lower Gravel cold intra-Saalian late 8 Corbets Tey Corbets Tey Upper Gravel cold intra-Saalian 8 (Botany Gravel ') Purfleet interglacial deposits warm intra-Saalian 9 Corbets Tey Lower Gravel cold intra-Saalian late 10 (LittleThurrock Gravel') Orsett Heath Orsett Heath Upper Gravel cold intra-Saalian 10 Swanscombe interglacial deposits warm Hoxnian 11 Orsett Heath Lower Gravel cold late Anglian late 12 1 From Schreve et al. (2002) assemblages suggested that four discrete Mammal with later, cooler temperate episodes within OIS 5 Assemblage-Zones (MAZs) may be recognized within classified as interstadials. the Lower Thames (Fig. 1), which are thought to rep resent OIS 11, 9 and a complex, dual-peaked OIS 7, Mammalian assemblages from the first post-Anglian all of which clearly pre-date the Last (Ipswichian) In interglacial. terglacial (OI substage 5e).The mammalian biostrati- graphical scheme thus corroborated and extended the The first of the late Middle Pleistocene interglacials is scheme of Bridgland (1994, 1995), established on the represented in the Lower Thames only in the Dart- basis of lithostratigraphical evidence. The Anglian/El- ford - Swanscombe area of Kent (Fig. 2), with the sterian glacial is here correlated with OIS 12, as is majority of the mammalian evidence coming from the widely favoured in Britain (Bowen et al., 1986, 1989; adjacent sites of Barnfield Pit at Swanscombe and Bowen, 1999; Rowe et al., 1999; Scourse et al., 1999) Dierden's Pit, Ingress Vale (Sutcliffe, 1964). and further afield (Sarnthein et al., 1986; Shackleton, This particular faunal grouping has been assigned 1987; Ehlers et al., 1991), although some Dutch and to the Swanscombe MAZ by Schreve (2001a), with German workers have correlated the Elsterian, or at taxa of biostratigraphical significance including the least the latest part of it, with OIS 10 (De Jong, 1988; extinct small