This paper reviews all available geological data on the Tajno Massif that intruded the Paleoproterozoic crystalline basement of NE Poland (Mazowsze Domain) north of the Teisseyre-Tornquist Zone, on the East European Craton. This massif (and the nearby Elk and Pisz intrusions) occurs beneath a thick Mesozoic-Cenozoic sedimentary cover. It has first been recognized by geophysical (magnetic and gravity) investigations, then by drilling (12 boreholes down to 1800 m). The main rock types identified (clinopyroxenites, syenites, carbonatites cut by later multiphase volcanic/subvolcanic dykes) allow characterizing this massif as a differentiated ultramafic, alkaline and carbonatite complex, quite comparable to the numerous massifs of the Late Devonian Kola Province of NW Russia. Recent geochronological data (U-Pb on zircon from an albitite and Re-Os on pyrrhotite from a carbonatite) indicate that the massif was emplaced at ~348 Ma (Early Carboniferous). All the rocks, but more specifically the carbonatites, are enriched in Sr, Ba and LREE, like many carbonatites worldwide, but depleted in high field strength elements (Ti, Nb, Ta, Zr). The initial 87 Sr/ 86 Sr (0.70370 to 0.70380) and eNd(t) (+3.3 to +0.7) isotopic compositions of carbonatites plot in the depleted quadrant of the Nd-Sr diagram, close to the “FOcal ZOne” deep mantle domain. The Pb isotopic data ( 206 Pb/ 204 Pb <18.50) do not point to an HIMU (high U/Pb) source. The ranges of C and O stable isotopic compositions of the carbonatites are quite large; some data plot in (or close to) the “Primary Igneous Carbonatite” box, while others extend to much higher, typically crustal δ 18 O and δ 13 C values The initial 87 Sr /86 Sr (0.70370 to 0.70380) and eNd(t) (+3.3 to +0.7) isotopic compositions of carbonatites plot in the depleted quadrant of the Nd-Sr diagram, close to “FOcal ZOne” (FOZO) deep mantle domain. The Pb isotopic data ( 206 Pb/ 204 Pb <18.50) do not point to an HIMU (high U/Pb) source. The ranges of C and O stable isotopic compositions of the carbonatites are quite large; some data plot in (or close to) the “Primary Igneous Carbonatite” box while others extend to much higher, typically crustal δ 18 O and δ 13 C values.

中文翻译：

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Tajno 超镁铁质-碱性-碳酸岩地块，波兰东北部：综述。地球物理学、岩石学、地质年代学和同位素特征

本文回顾了关于侵入东欧克拉通 Teisseyre-Tornquist 带以北的波兰东北部古元古代结晶基底的 Tajno 地块的所有可用地质数据。该地块（以及附近的 Elk 和 Pisz 侵入体）发生在厚厚的中新生代沉积覆盖层之下。它首先被地球物理（磁力和重力）调查所识别，然后是钻探（12 个钻孔至 1800 m）。确定的主要岩石类型（单斜辉石岩、正长岩、后来多相火山/亚火山岩脉切割的碳酸盐岩）可以将这个地块表征为一个分化的超镁铁质、碱性和碳酸岩复合体，与俄罗斯西北部晚泥盆世科拉省的众多地块相当。最近的地质年代学数据（钠长石锆石的 U-Pb 和碳酸岩磁黄铁矿的 Re-Os）表明该地块位于~348 Ma（早石炭世）。所有的岩石，尤其是碳酸盐岩，都富含 Sr、Ba 和 LREE，就像世界各地的许多碳酸盐岩一样，但缺乏高场强元素（Ti、Nb、Ta、Zr）。碳酸岩的初始 87 Sr/86 Sr（0.70370 至 0.70380）和 eNd（t）（+3.3 至 +0.7）同位素组成位于 Nd-Sr 图的耗尽象限，靠近“焦区”深部地幔域. Pb 同位素数据 (206 Pb/204 Pb <18.50) 未指向 HIMU（高 U/Pb）源。碳酸盐岩C、O稳定同位素组成范围较大；一些数据绘制在（或接近）“原生火成岩碳酸岩”框中，而另一些则扩展到更高，典型地壳 δ 18 O 和 δ 13 C 值 碳酸岩的初始 87 Sr /86 Sr（0.70370 至 0.70380）和 eNd(t)（+3.3 至 +0.7）同位素组成绘制在 Nd-Sr 图的耗尽象限中，靠近“焦点区”（FOZO）深地幔域。Pb 同位素数据 (206 Pb/204 Pb <18.50) 未指向 HIMU（高 U/Pb）源。碳酸盐岩C、O稳定同位素组成范围较大；一些数据绘制在（或接近）“原生火成岩碳酸岩”框中，而另一些则扩展到更高的值，通常是地壳 δ 18 O 和 δ 13 C 值。Pb 同位素数据 (206 Pb/204 Pb <18.50) 未指向 HIMU（高 U/Pb）源。碳酸盐岩C、O稳定同位素组成范围较大；一些数据绘制在（或接近）“原生火成岩碳酸岩”框中，而另一些则扩展到更高的值，通常是地壳 δ 18 O 和 δ 13 C 值。Pb 同位素数据 (206 Pb/204 Pb <18.50) 未指向 HIMU（高 U/Pb）源。碳酸盐岩C、O稳定同位素组成范围较大；一些数据绘制在（或接近）“原生火成岩碳酸岩”框中，而另一些则扩展到更高的值，通常是地壳 δ 18 O 和 δ 13 C 值。