Late Silurian–Early Devonian tuffites from the Małopolska and Łysogóry blocks reflect arc-back-arc magmatic activity on the southern margin of Laurussia

Zircon U-Pb dating of tuffites within the upper Silurian greywackes in the southern part of the Holy Cross Fold Belt gives a result of 419.91 ±1.7 Ma, which indicates they are of Přídolí age. Geochemical studies of Přídolí tuffites from the Małopolska Block, an Emsian tuffite from the Łysogóry Block in the Holy Cross Fold Belt and a Přídolí tuffite from the Bardo Unit in the Central Sudetes indicate that they were formed in a similar tectonic setting related to post-orogenic, continental arc-back-arc magmatism, developed along the southern margin of Laurussia, correlated with the Rhenohercynian Zone. In terms of their geochemical pattern, the tuffites are similar to the upper Silurian–Lower Devonian igneous rocks in Germany, Ukraine (Podolia) and Moldova, which were probably formed along the same subduction zone, during an early stage of the continental arc-back-arc magmatic activity.