The Tajno ultramafic-alkaline-carbonatite massif, NE Poland: a review. Geophysics, petrology, geochronology and isotopic signature

Alkaline magmatism from the Lublin–Baltic area of Poland (SW slope of the East European Craton)—Manifestation of hitherto unrecognized early Carboniferous igneous province

“…However, recently acquired high-quality SHRIMP U-Pb ages on zircon and 40 Ar/ 39 Ar plateau ages on whole rock or plagioclase are consistent across the whole LBMIP, mostly in the narrow range of c. 348 to 338 Ma, that is upper Tournaisian to lower Visean (Figures 1b, 7; Supportive information S4; e.g. Demaiffe et al, 2013;Motuza et al, 2015;Pańczyk & Nawrocki, 2015;Krzemińska & Krzemiński, 2017;Wiszniewska et al, 2020). The upper Tournaisian age of volcaniclastics and pyroclastics derived from the LBMIP is only documented by stratigraphic constraints (Krzemiński, 1999;Muszyński et al, 1996).…”

“…The most intensive alkaline igneous activity within the LBMIP occurred in the Mazury High, separating the Baltic and the Lublin basins (Figure 1b; Supportive information S1), where the entire pre-Permian sedimentary cover and upper part of crystalline basement were eroded (Figure 2). The preserved root part of an extensive volcanic system comprises the Tajno pyroxenite-syenite-carbonatite complex, the Ełk syenite massif and the Pisz gabbro-syenite massif (Figures 1b, 2;Demaiffe et al, 2013;Wiszniewska et al, 2020), well documented by numerous boreholes due to their moderate recent burial depth (<1000 m). In the SW part of the Mazury High, the large Mława syenite massif is buried deeper (c. 2500-3500 m) and penetrated by four boreholes (Krzemińska & Krzemiński, 2012).…”

“…The massifs are the sources of the prominent magnetic anomalies, as documented by studies of core samples from numerous wells (comp. : Wybraniec & Cordell, 1994; Petecki & Rosowiecka, 2017; Wiszniewska et al, 2020, and references therein). The deeper buried Carboniferous Mława syenite massif in the SW part of the Mazury High is the source of the large magnetic and gravimetric anomaly (comp.…”