Vertebrate Tracksites in the Obernkirchen Sandstone (Late Berriasian, Early Cretaceous) of Northwest Germany— Their Stratigrap
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Pala¨ontol Z (2012) 86:231–267 DOI 10.1007/s12542-012-0131-7 REVIEW ARTICLE Vertebrate tracksites in the Obernkirchen Sandstone (late Berriasian, Early Cretaceous) of northwest Germany— their stratigraphical, palaeogeographical, palaeoecological, and historical context Jahn J. Hornung • Annina Bo¨hme • Torsten van der Lubbe • Mike Reich • Annette Richter Received: 26 November 2010 / Accepted: 25 October 2011 / Published online: 14 March 2012 Ó The Author(s) 2012. This article is published with open access at Springerlink.com Abstract The northern German Lower Cretaceous are inaccessible today. Additionally, historical descriptions Bu¨ckeberg Formation yields numerous dinosaur tracksites, of the tracks were of highly variable quality and often some of which have produced material of impressive qual- published in remote and today nearly unobtainable sources. ity. Stratigraphically, the localities are concentrated in the Here we provide a catalogue of 13 tracksites compiled from Obernkirchen Sandstone, a thin subunit within this forma- the literature and some new observations. Of these 13 tion. The Obernkirchen Sandstone represents mainly a tracksites, only five are still accessible and currently under sandy barrier to back-barrier and lagoonal setting within a study. Descriptions of each locality are provided, with a limnic deltaic facies complex, which was deposited during comprehensive compilation of existing data on lithofacies, the late Berriasian (Cypridea alta formosa ostracod sub- stratigraphy, palaeogeography and palaeoecology of the zone) in the southeast of the Lower Saxony Basin, northwest Obernkirchen Sandstone and equivalent strata. A short Germany. A few tracksites occur more proximally in coeval review of the track-bearing lithofacies assemblage indicates fluvial deposits. Dinosaur footprint assemblages were left by that the outcrop areas have distinctly different facies and ornithopods, theropods, sauropods, ankylosaurs, and small, environments, and, therefore, track-bearing horizons can bipedal ornithischians. Other vertebrate tracks are those of only be correlated stratigraphically between adjacent out- turtles and, possibly, crocodilians. Due to the decrease in crops. For this reason, the identification of a megatracksite sandstone quarrying in recent decades, many old tracksites in the Obernkirchen Sandstone is currently regarded as premature and uncertain. J. J. Hornung (&) Á A. Bo¨hme Keywords Vertebrate tracks Á Dinosauria Á Cretaceous Á Geowissenschaftliches Zentrum, Abt. Geobiologie, Berriasian Á Obernkirchen Á Mu¨nchehagen Á Germany Georg-August-Universita¨tGo¨ttingen, Goldschmidtstr. 3, 37077 Go¨ttingen, Germany e-mail: [email protected] Kurzfassung Die unterkretazische Bu¨ckeberg-Formation Nordwest-Deutschlands ist reich an Fundstellen von Di- A. Bo¨hme e-mail: [email protected] nosaurierfa¨hrten, von denen einige hervorragend erhaltenes Material lieferten. Diese Fundstellen sind stratigraphisch T. van der Lubbe Á A. Richter auf ein geringma¨chtiges Intervall, den Obernkirchen- Niedersa¨chsisches Landesmuseum Hannover, Sandstein, konzentriert. Der Obernkirchen-Sandstein Willy-Brandt-Allee 5, 30169 Hannover, Germany e-mail: [email protected] repra¨sentiert eine sandige Barrieren- und Lagunen-Fazies innerhalb eines limnisch-deltaischen Fazieskomplexes, der A. Richter e-mail: [email protected] wa¨hrend des spa¨ten Berriasiums (Cypridea alta formosa Ostrakoden-Subzone) im Su¨dosten des Niedersa¨chsischen M. Reich (&) Beckens abgelagert wurde. Einige Fa¨hrtenfundstellen lie- Geowissenschaftliches Zentrum, Museum, Sammlungen gen auch in etwas proximaleren, gleichaltrigen, fluviatilen and Geopark, Georg-August-Universita¨tGo¨ttingen, Goldschmidtstr. 1-5, 37077 Go¨ttingen, Germany Ablagerungen. Erzeuger der Dinosaurierfa¨hrten waren e-mail: [email protected] Ornithopoden, Theropoden, Sauropoden, Ankylosaurier 123 232 J. J. Hornung et al. sowie kleine, bipede Ornithischia. Weitere Wirbeltier- vertebrates, including turtles, crocodiles, and dinosaurs Fa¨hrten wurden von Schildkro¨ten und mo¨glicherweise (e.g. Roemer 1836; von Meyer 1841, 1857, 1859; von Krokodilen hinterlassen. Aufgrund des Ru¨ckgangs im Meyer in Dunker 1846). Sandstein-Abbau im Verlauf der vergangenen Jahrzehnte Although extremely abundant and probably known to sind viele der alten Fa¨hrten-Fundstellen heute nicht mehr quarry workers for centuries, reliable accounts of dinosaur aufgeschlossen. Historische Beschreibungen sind von un- tracks were not reported before the middle of the 19th terschiedlicher Qualita¨t und ha¨ufig nur in schwer erha¨ltli- century. According to Grabbe (1881), the mining supervi- chen Quellen publiziert. Hier pra¨sentieren wir einen sor Heidtmeier reported the occurrence of a trail of con- Katalog mit 13 Fundstellen, zusammengestellt aus Litera- secutive tracks more than 100 m long which was turquellen und neuen Untersuchungen. Nur fu¨nf Fundstellen uncovered in a quarry near Wendthagen in the 1850s. sind heute noch zuga¨nglich und derzeit Gegenstand wei- Unfortunately, there are no other records of this find. terer Forschungen. Sa¨mtliche Fundstellen werden vorge- In 1879, the first dinosaur tracks reported from Germany stellt und der Kenntnisstand u¨ber Lithofazies, Stratigraphie, rather sneaked into the scientific record. At the December Pala¨ogeographie und Pala¨oo¨kologie des Obernkirchener meeting of the Deutsche Geologische Gesellschaft (Ger- Sandsteins zusammengefasst. Lithofazies-Daten zeigen, man Geological Society), held on 3 December 1879, in dass eine feinstratigraphische Korrelation individueller Berlin, Wilhelm Hauchecorne presented a letter and a Horizonte innerhalb des Sandstein-Komplexes nur zwi- drawing by mining engineer Fritz F. von Du¨cker, in which schen sehr eng benachbarten Aufschlu¨ssen mo¨glich ist und he reported the discovery of ‘‘bird tracks’’ in the Bad deutliche Faziesunterschiede zwischen den Fa¨hrtenvor- Rehburg area. At the same meeting, Wilhelm Dames kommen bestehen. Daher erscheint die derzeitige commented that these tracks were very similar to those Datengrundlage als nicht hinreichend, um den Obernkirchen- from the English Wealden, which had been identified as Sandstein in seiner Gesamtheit als Megatracksite zu dinosaur tracks shortly before. Both contributions consisted charakterisieren. of a single sentence each, included in the published pro- ceedings of the meeting (Dames in Beyrich et al. 1879; Schlu¨sselwo¨rter Wirbeltier-Fa¨hrten Á Dinosauria Á Hauchecorne in Beyrich et al. 1879). Kreide Á Berriasium Á Obernkirchen Á Mu¨nchehagen Á The geologist Carl Struckmann was the first researcher Deutschland to provide a scientific description of these tracks. During the summer of 1879, more tracks were found at Wo¨lping- hausen (Rehburg mountains, see locality 4 below) and Introduction immediately vividly discussed in local press reports (Anonymous 1879a, b). These early discussions, led mostly The Berriasian Bu¨ckeberg Formation is well-known for its by Struckmann, centred around a ‘‘bird-like’’ animal as a wealth of dinosaur tracks (Ballerstedt 1905; Dietrich 1927; potential trackmaker. This view was not left unchallenged– Lehmann 1978), but their documentation is mostly con- in fact, the ornithologist Wilhelm Pralle suggested the tri- fined to isolated specimens or localities. Important dis- dactyl imprints had been made by the mani (!) of giant coveries of the last two decades are mostly reported in anurans (Anonymous 1879b). In 1880, Struckmann sub- general overviews or abstracts (Wings et al. 2005a; stantiated his results and published the first papers on the Lehmann 2006; Lehmann et al. 2006; A. Richter et al. ‘‘Ornithoidichnites’’, referring them to the dinosaur 2007; U. Richter et al. 2007; Richter et al. 2009; Richter Iguanodon (Struckmann 1880a, b). 2007;Bo¨hme et al. 2009; van der Lubbe et al. 2009). To corroborate his identification, Struckmann sent a Nearly all tracksites from the Bu¨ckeberg Formation are gypsum cast of one of the tracks to Louis Dollo, in Brus- located stratigraphically within the Obernkirchen Sand- sels, who was the most important authority on Iguanodon stone, a thin subunit exposed in the northern and western at the time, and was studying the famous ‘‘herd’’ of this vicinities of Hannover. At least since early medieval times, dinosaur found at the Bernissart coal mine in 1878. Dollo this sandstone has been a valued dressing stone and (1883: 113) reported a perfect match of this track with the building material. Intensive quarrying since the 11th cen- pedal skeleton of a specimen he identified as Iguanodon tury AD led to the use of the nearly pure quartzose sand- mantelli. stone in hundreds of buildings and monuments across At least two specimens of Struckmann’s material are northern Germany, Europe, and in places as far abroad as still preserved in the Niedersa¨chsisches Landesmuseum, Jakarta, Indonesia (Hamm 1938; Graupner 1977; Harnack Hannover. One right pes impression of a large ornithopod 1989; Broschinski 2004). Since the beginning of the 19th (NLMH 105.747, Fig. 1) can be identified as the specimen century, this formation became increasingly well-known as which was deemed an exception by him, as he believed it a lagerstaette for rare but well-preserved Cretaceous was tetradactyl instead of tridactyl (Struckmann 1880a: 99, 123 Vertebrate tracksites in the Obernkirchen Sandstone 233 Fig. 1 Right pes impression (hypichnial relief) of a large ornithopod public collection. a Specimen as preserved today; b Specimen as (NLMH 105.747), Bu¨ckeberg