Baltica and the Cadomian orogen in the Ediacaran–Cambrian: a perspective from SE Poland

• DOI: 10.1007/s00531-020-01858-0
• Publication Date: 2020-04-19T10:02:35Z
• Authors: Andrzej Żelaźniewicz; Teresa Oberc-Dzie...; Jiri Slama
• Keywords: Baltica; Rodinia; Supercontinent; Laurentia; Siliciclastic; Overprinting

Abstract In the supercontinent of Rodinia, Baltica occurred next to Amazonia, then two drifted away when Rodinia broke up. By end Neoproterozoic, became an independent continent. At that time, Timanide orogen developed at its modern northeastern margin. most paleogeographical reconstructions, opposite (SW, Tornquist) edge faced Tornquist Ocean and remained just a passive margin till arrival Gondwana-born East Avalonia in late Ordovician. However, preliminary isotopic studies detrital zircons from succession hinted rock components Gondwana derivation reached already early Cambrian. this paper, we examine 18 drill-cores Ediacaran-Cambrian Ordovician siliciclastic rocks tectonostratigraphic units along SW–NE transect Upper Silesia (USB) via Małopolska (MB) Holy Cross Mts (HCM) European Platform (EEP), SE Poland, terms provenance data gained LA-ICP-MS SHRIMP analyses 32 zircon samples. Rocks all revealed abundant Cadomian 0.7–0.55 Ga (15–50% total analyzed grains) other grains yielded peaks 0.9–1.2, 1.4–1.6, 1.8–2.2, 2.7–3.0 assignable rather than Amazonia. Such age spectra USB, HCM EEP prove proximity peripheral (peri-Gondwanan) fragments Baltica. These formed Teissyere-Tornquist Terrane Assemblage (TTA) obliquely docked overrode thinned southwestern which earlier accumulated Neoproterozoic rift deposits. Our show Ediacaran-early Cambrian, parts orogenic belt accreted