[In:] Winchester, J. A. & Pharaoh, T. C. & Verniers, J.: Palaeozoic Amalgamation of Central Europe. – Geological Society, London, Special Publications, 201: 115-131, Fig. 1-6; London. Chitinozoa
and Nd isotope stratigraphy of the Ordovician rocks in the Ebbe Anticline, J.
SAMUELSSON1,2,3, A. GERDES4, L. KOCH5, T.
SERVAIS6, J. VERNIERS1 1Research
Unit Palaeontology, Department of Geology and Pedology, Ghent University,
Krijgslaan 281 / S 8, B-9000 Ghent, Belgium Abstract: Strongly tectonised Ordovician rocks appear in the Ebbe Anticline (Rheinisches Schiefergebirge), West Germany. These fine-grained detrital rocks of the Herscheider Schichten are divided into the Plettenberger Bänderschiefer, Unterer (Kiesberter) Tonschiefer, (Rahlenberger) Grauwackenschiefer, and the Oberer (Solinger) Tonschiefer. The scope of this investigation was to improve the dating of the entire Ordovician succession, but especially the Oberer (Solinger) Tonschiefer. We used chitinozoans, Palaeozoic microfossils of high biostratigraphic value, and Nd isotopes, which previously have been used for correlation and terrane affinity analysis. Chitinozoan preservation is poor, but some taxa could be confidentially identified to the species level. The eNd(t) values obtained from the Ordovician succession range from -8.0 to -9.1. Joint evaluation of chitinozoan and Nd isotope data together with previously known age-ranges suggest the following ages for the Herscheider Schichten: Plettenberger Bänderschiefer (early Abereiddian, earliest Llanvirn), Unterer (Kiesberter) Tonschiefer (early to mid Abereiddian, early Llanvirn), (Rahlenberger) Grauwackenschiefer (Aurelucian, earliest Caradoc), and Oberer (Solinger) Tonschiefer (late Caradoc). The Ebbe eNd(t) values are most readily compared with eNd(t) values from Avalonia, and we therefore support the inclusion of the Ordovician rocks of the Ebbe Anticline in that palaeocontinent.
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