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Paleomagnetic and petrological analyses were performed on Devonian carbonate rocks from the Kielce region (Janczyce 1 borehole, Dule, Łagowica escarpment, Budy Quarry) in the Holy Cross Mts. Rock samples were selected from localities with different degree of thermal alteration, diversified lithology and stratigraphy. Investigated carbonates, excluding those from the Budy Quarry, revealed traces of the Early Permian remagnetization related to magnetite. The intensity of the Late Variscan remagnetization is linked to rocks affected by the second stage of dolomitization with increased thermal maturity in the northern part of the Kielce region. The magnetic signal is probably related to rocks’self-cooling, fixed as a result of the latest Carboniferous to Early Permian uplift.
A wildflysch sequence recently recognized in the Görlitzer Schiefergebirge/western Kaczawskie Mts. boundary zone permits the characterization of the westernmost Kaczawa Unit as a chaotic complex. The cherts,many of which contain numerous radiolarians, occur as exotic clasts within the olistostrome deposits of the wildflysch. They are associated with allochthonous blocks of blueschist, andesite pillow lavas and pyroclastic rocks, flysch facies clastic rocks, mudstones (often of black shale lithology) and carbonates. The conodonts extracted from the grey-greenish radiolarite cherts indicate a mid-Famennian age (Early rhomboidea Zone to Early marginifera Zone). The conodont-bearing radiolarite clasts reveal no trace of a tectonometamorphic fabric. Their 4-4.5 conodont colour alteration index (CAI) indicates that the rock underwent low-temperature (250-285C) thermal alteration. The lack of thermal overprint in the olistostrome matrix allows this alteration to be interpreted as a part of the tectonothermal, post-mid-Famennian evolution of the source area. A number of the exotic blocks of unmetamorphosed volcanic rocks associated with the chert exotics seems to indicate igneous (volcanic) activity as the reason for the chert alteration. The fact that exotic blocks of the Devonian chert have been found as clasts within deposits earlier believed to represent Upper Proterozoic (Cadomian) flysch suggests the need for reassessement of the extent of Cadomian rocks in the westernmost Sudetes.
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