Poziomy sporowe famenu i turnieju z otworu wiertniczego Kowala 1

Abstract

W utworach famenu z profilu Kowala 1 wyróżniono cztery poziomy sporowe oraz kilkanaście zon wg podziału stosowanego w Belgii. Pewne gatunki, których pierwsze pojawienie się stanowi w Belgii podstawy wyróżnienia zon sporowych, są w Kowali nieobecne, podczas gdy inne pojawiają się tu w innym czasie niż na zachodzie (co wynika z danych konodontowych). W obecnej chwili brak kryteriów palinologicznych, które pozwoliłyby na szczegółowszy podział utworów famenu (do Fa2c) w Górach Świętokrzyskich. Natomiast w utworach granicznych dewonu i karbonu w tym profilu występują zespoły spor, na podstawie których można je korelować z utworami dotychczasowego rejonu typowego dla tej granicy w Reńskich Górach Łupkowych. Dane sporowe co do położenia tej granicy w profilu Kowala 1 są w przybliżeniu zgodne z innymi danymi biostratygraficznymi.

Spore zones of Famennian And Tournaisian deposits from the Kowala 1 borehole

The subsurface section Kowala 1 penetrated under Quaternary cover some lowermost Carboniferous and Devonian deposits resting on Cambrian ones. Both the Carboniferous and the Devonian deposits are mainly carbonates. Their thicknesses are about 3 m and about 1000 m respectively. Spore assemblages have been obtained from the Famennian and the Carboniferous deposits, from the part of the profile which is well dated on conodonts and other faunas. An attempt was made to use for the stratigraphical division of these deposits the spore zonal schemes established by J.B. Richardson and D.C. McGregor (1986) and by M. Streel et al. (1987). It appears that even the former division which includes very wide zones can not be fully applied to the Famennian deposits of the Holy Cross Mountains, because the relevant spore species either do not occur there or they appear at different stratigraphical levels than in the West. This is even more true when the latter, much more detailed division is concerned. Four different successive spore assemblages may be distinguished in the Famennian deposits of Kowala (Fig. 1 and 2). The lowermost one is characterised by the presence of Diducites versabilis (Kedo) Van Veen and the successive ones by the first appearances of Archaeozonotriletes Jamenensis Naumova, Konoxisporites literatus (Waltz) Playford and Verrucosis porites nitidus (Naumova) Playford. Thy correspond to the zones (V), GF, LL and LN, but the conodont data indicate that between Western Europe and the Holy Cross Mountains, the GF and LL zones are diachronous. The lowermost Carboniferous assemblage is characterised by the lack of Retispora lepidophyta (Kedo) Playford, Rugospora radiata (Juszko) Bywszewa, and by the presence of Vallatisporites pusillites (Kedo) Dolby et Neves. The comparison of the spore and conodont data obtained at Kowala suggests that some spore species appear in the Holy Cross Mountains at different stratigraphical levels than they do in the West. Archaeozonotriletes famenensis Naumova appears probably in the Upper Subzone of the P. crepida Zone, Rugospora radiata (Juszko) Bywszewa, Retispora lepidophyta (Kedo) Playford and Knoxisporites literatus (Waltz) Playford appear at the same level, probably in Lower P. expansa Subzone. Vallatis porites pusillites (Kedo) Dolby et Neves apperas higher in this zone or in the S. praesu1cata Zone.