A Hidden Alkaline and Carbonatite Province of Early Carboniferous Age in Northeast Poland: Zircon U-Pb and Pyrrhotite Re-Os Geochronology

• Published in: The Journal of Geology
• Main Authors: Demaiffe, Daniel, Wiszniewska, Janina, Krzemińska, Ewa, Williams, Ian, Stein, Holly, Brassinnes, Stéphane, Ohnenstetter, Daniel, Deloule, Etienne
• Other Authors: Laboratoire Géochimie, Traçage Isotopique, Minéral et élémentaire - G-Time (Bruxelles, Belgium), Polish Geological Institute = Państwowy Instytut Geologiczny (PIB), Research School of Earth Sciences Canberra (RSES), Australian National University (ANU), Applied Isotope Research for Industry and Environment Program, Department of Geosciences Colorado State University, Colorado State University Fort Collins (CSU)-Colorado State University Fort Collins (CSU), Physics of Geological Processes Oslo (PGP), Department of Physics Oslo, Faculty of Mathematics and Natural Sciences Oslo, University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences Oslo, University of Oslo (UiO)-University of Oslo (UiO)-Department of Geosciences Oslo, University of Oslo (UiO)-University of Oslo (UiO), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Kola Peninsula; karelia*; kola peninsula
• Online Access: https://hal.univ-lorraine.fr/hal-01761424; https://doi.org/10.1086/668674

International audience Extensive geophysical investigations in NE Poland in the 1950s and 1960s led to the discovery of an alkaline and carbonatite magmatic province buried under thick (600–800 m) Meso-Cenozoic cover north of the Trans-European Suture Zone, or Tornquist Line. Drilling focused on geophysical anomalies identified three intrusions in the Paleoproterozoic metasedimentary and metavolcanic rocks of the Mazowsze Domain: the Pisz gabbro-syenite massif, the Ełk syenite massif, and the small, differentiated Tajno body consisting of clinopyroxenite cumulates and syenites crosscut by carbonatite veins. Emplacement ages for these intrusions have been obtained by (1) zircon U-Pb geochronology on a gabbro from Pisz, a syenite from Ełk, and an albitite from Tajno and (2) a Re-Os model age for pyrrhotite from a Tajno carbonatite. The ages measured by both methods fall in the narrow range 354–345 Ma (Early Carboniferous: Tournaisian). This is slightly younger than the Late Devonian (380–360 Ma) Kola Peninsula alkaline and carbonatite province (20 intrusions) of NE Russia and Karelia but is of comparable age to the first manifestations of the long-lasting (∼100 m.yr.) Carboniferous to Permian magmatic event (360–250 Ma) manifest in northern Europe (from the British Isles to southern Scandinavia, the North Sea, and northern Germany) in the foreland of the Variscan orogeny (in the so-called West European Carboniferous Basin) and the East European Craton.