Nowe dane o karbonie w zachodnim obrzeżeniu Gór Świętokrzyskich

Abstract

NEW DATA ON THE CARBONIFEROUS IN THE WESTERN MARGIN OF THE ŚWIĘTOKRZYSKIE MTS.SummaryAlccording to the programme of prospection drillings, bore hole Łopuszno IG-l has been made in the western part of the Świętokrzyskie Mts. (Fig. 1). The following are formations pierced by the bore hole considered: Quaternary (6.9 m), Triassic (1418.0 m), Zechstein (1774.2 m) and Carboniferous, non-pierced down to a depth of 2073.0 m. The Permian-Carboniferous boundary begins with an angular discordance of beds (Zechstein 13°, Carboniferous 30° at the boundary zones) and shows lithological variation of deposits (Fig. 2). The Zechstein deposits examined down to a depth of 1671.1 m disclose macrofauna, microfauna and flora representatives that prove the Lower Zechstein age (Table 1), as well as the pollen grains otf Gymnospermae. The flora here encountered is analogous to that known to occur in the Lower Zechstein deposits at Kajetanów in the region at the Świętkorzyskie Mountains. So far, this has been the only occurrence site of the oldest representatives of Coniferae. The Carboniferous formations are developed here as clastic deposits intensely cracked and slickensided, with their dip reaching up to 80° at places. At the top part, these are barren deposits with a slight amount of flora below this part. At a depth at l805.5-1826.9 m these deposits reveal, beside the flora representatives, also insignificant fauna. Well determinable forms are found among the abundant fauna only at a depth of 1826.0-2073.0 m. These allowed the present author to refer this part to the horizon Goniatites granosus. The sub-horizon Goγ1 may be seen at a depth of 2067.0 m, but the form Goniatites cf. granosus granosus is thought to appear already at a depth of 2059.0 m. A lack of the fauna representatives, characteristic of the sub-horizon Goγ2, forced the present author to refer the whole of the Carboniferous strata pierced at Łopuszno to the horizon Goγ. The actual thickness of these deposits amounts to about 175 m. The Carboniferous deposits have been studied by means of microfloristic method (19 samples), and the results obtained are now under examinations. The Carboniferous section from Łopuszno seems to be analogous to that of the Gałęzice syncline in the Świętokrzyskie Mts. (Table 2), since this latter reveals also index fauna of the horizon Goγ, and of the subhorizon Goγ1 (H. Żakowa, 1967, 1968). This analogy concerns both lithofacies and biofacies. These facts and the lack of Upper Carboniferous deposits in either of the regions prove the similar development of Carboniferous cycle, and the identical sedimentary conditions in the uppermost Upper Visean. It should be added here that in the western marginal area of the Świętokrzyskie Mts. the Carboniferous underlying Permian and Triassic has been found to occur only in the following bore holes: Radoszyce 3 (only with the index fauna of the horizon Goα), Ruda Strawczyńska (Tournaisian) and Rykoszyn-Skałka, near Gałęzice. The considerable thickness of the Carboniferous deposits at Radoszyce (Table 2) points to the sedimentation in a tectonically active zone of the marine basin, which, according to the present author, did not cover the region of Łopuszno at the time of the lowermost Upper Visean. A discovery of the horizon Goniatites granosus at Łopuszno is a new registered site of this kind in Poland. So far, the index fauna of the horizon Goγ has been ascertained to occur at few points only, i.e. in the Świętokrzyskie Mountains (Gałęzice), in the Fore-Sudetic Monocline (bore holes: Lamki 1, Mąkoszyce 1, Ostrzeszów 1), in the Silesian-Cracow Upland (bore hole Gołonóg 1), and in the Nida Trough (bore holes Słomniki 1, Węgrzynów 1, Pągów 1, Marszowice 1, Milianów 1).