Nowe dane o karbonie synkliny kieleckiej (Góry Świętokrzyskie)

Abstract

Omówiono litologię i stratygrafię profilów turneju z 2 przekopów usytuowanych na północnym skrzydle synkliny oraz profile wizenu, głównie górnego, z 5 przekopów z jądrowej części jednostki. Tu należą one do poziomu Goniatites crenistria i niższej części poziomu G. striatus. Oznaczono mikro- i makrofaun~ oraz nieliczną mikro- i makroflorlę. Skały karbonu są intensywnie pocięte podłużnymi i poprzecznymi dyslokacjami z lokalnymi strefami nasunięć, a takie odkształcone w formie wąskopromiennych synklin i antyklin. Zaburzenia tektoniczne i brak ciągłości profilów uniemożliwiają pełną ocenę miąższości i wyznaczenie granic poszczególnych jednostek chrono- i biostratygraficznych w synklinie kieleckiej. NEW DATA ABOUT THE CARBONIFEROUS OF THE KIELCE SYNCLINE (THE HOLY CROSS MTS)Here were discussed lithology, stratigraphy and tectonic deformations of the Tournaisian profiles from northern limb of the Kielce Syncline (Śluchowice housing estate) and also the Visean profiles, mainly of the Upper Visean (Czarnów quarter), from its core part (Fig. 1).Two trenches (length of first is about 160.0 m and of second - over 50.0 m) were analysed from the first of mentioned areas. They crossed the western part of narrow “lense” of the Carboniferous of hitherto unknown profile, located by J. Czarnocki in 1938 on his geological map, the Kielce scheet (H. Żakowa, J. Malec, 1990). In the longer trench the Lower Tournaisian deposits, contained various organic remains (Tab. 1; PI. I, Figs 1-7, 10), were noted on a distance of about 100 m (estimated thickness no less than 50.0 m) and described later as three profiles of varied length (11-IV, Fig. 2A). There occur the cherry-red and dark-grey claystones and clayslates, intercalations of clayey radiolarites, tuffogenic (?) stripes and marly deposits, more frequent in southern part of studied profile, close to undetaily known boundary of the Famennian series. In the shorter trench, on the distance of about 25.0 m, were found deposits of the upper Middle Tournaisian - Lower Upper Tournaisian age, dated with the radiolarian assemblage (H. Żakowa, M. Paszkowski, 1989), which are laid with dislocation contact on marly-calcareous deposits of the Famennian (Fig. 2B). The Tournaisian sequence consists mainly of grey and grey-green claystones with phosphorite concretions at the top, rarely of radiolarites and tuffites (?).Five trenches (I-IVb) were analysied on the second studied area, located in core part of the syncline. Their lengths were from 12.0 up to 51.0 m and the bed thickness changed from 3.0 up to 20.0 m (Figs 3, 4). These studies confirmed the occurrence of the Upper Visean, hitherto described according some inaccurate data (P. Filonowicz, H. Żakowa, 1973; Żakowa, 1974). Recently found goniatites allowed to distinguish horizons and subhorizons, dating these deposits for time interval: the Goniatites crenistria Zone – lower part of the G. striatus Zone (Fig. 5; H. Żakowa, 1992). Other macrofauna, microfauna, micro- and macroflora (Tab. 2; PI.1, Figs 8, 9; PI. PI, Figs 1-7) were noticed there also and many taxons of them documented the Upper Visean age of these deposits. There occurr also - besides of claystones and clayslates, known from the Upper Visean profile (H. Żakowa, 1974) - beds with phosphorite and ferriferous voncretions, numerous tuffitic (?) intercalations and rare radiolarites. The Lower and Middle Visean deposits, locally noticed and documented with radiolaria assemblages, consist of dark-grey claystones, sometimes siliceous, with phosphorite concretions and tuffites (?). These features are inadequate for correlation of studied series with the profiles of the same age from the Holy Cross Mts as well as with deposits of so called 1 and 2 unites. The Visean rocks from core part of the Kielce Syncline are more tectonically disturbed than it was earlier supposed. On southern part of studied area within the Visean sequence occurred the fold elements of second order - anticline and syncline (Figs 3, 4 - trenches I-II) but the folds of smaller amplitude are known from the eastern part of area. There, in local overthrust zone, the Lower Visean beds build the tight anticlinal form and tight overturned southward fold with truncated lower limb (northern wail of IVb trench). Everywhere the beds are cutted by dislocations, mainly longitudinal with inclined northward fault surfaces, also in northern part of core of the Kielce Syncline (III trench). The Tournaisian deposits in the northern synclinal limb are similary strongly dislocated and locally folded in form of tight anticlines and synclines. The bed strikes are between 75-135° and they are inclined at varied angles south- and northward. Tectonic disturbances and discontinuity of profiles (Fig. 5) unable proper estimation of bed thickness and marking of boundaries of individual chrono- and biostratigraphic units, hitherto distinguished in studied artificial outcrops.