Stratygrafia sporowa karbonu środkowo-wschodniej Polski

Abstract

Spore stratigraphy of the Carboniferous of Central-Eastern Poland Miospore investigations were carried out on the Carboniferous sedimentis penetrated by boreholes (located in the south-eastern part of the margin of the East-European platform (fig. 1). On the basis of data obtained, spore zones (I—VII) and subzones (Va, b, Via, b) were distinguished and correlated with the Heerlen division (Table 1). Brief characterization of each zone is as follows: Zone I: Murospora aurita (Upper Visean) This zone extends from the sole of the Carboniferous sediments to the upper boundary of occurrence of the species Murospora aurita, which is accompanied by: Murospora tripulvinata, M. margodentata, Trimurispora sp., Simozonotriletes strigatus, Anapiculatisporites concinnus, Procoronaspora serrata, Diatomozonotriletes jubatus, D. cervicornutus, D. ubertus var delicata. The spore assemblage is supplemented by several species passing into the higher zone, as well as by those which have a long stratigraphic range. Zone II: Tripartites ruigosus (Lower Namurian A) It is an „acme” zone of the genus Tripartites. It is represented by a dozen or so species, the index species T. rugosus included. The upper boundary of the zone is defined by extinction of most species of Tripartites, as well as of such species as Diatomozonotriletes ubertus, Trilobozonotriletes incisotrilobus, Yashimanisporites, trivalvis, Schulzospora primigenia f. elongata, Protodissaccites iplicatus, Auroraspora micromanifestus, Chaetosphaerites variabilis. The species Reticulatisporites carnosus, Sinuspores sinuatus and very scarce Laevigatosporites have been found in this zone. Abundant are Schulzospora, Chaetosphaerites Rotaspora, and others. Zone III: Chaetosphaerites pollenisimilis (Upper Namurian A) The lower boundary of this zone is defined by disappearance of most species of Tripartites whereas the upper one by extinction of the index species Ch. pollenisimilis as well as of some species also known from the lower zones, e. g. Rotaspora fracta, R. knoxi, Anapiculatisporites hispidus, Procoronaspora fasciculata, Remysporites magnificus. New specis, such as Ahrensisporites guerickei, Crassispora kosankei, Schopfipollenites ellipsoides, start their development. Zone IV: Densosporites-Cristatisporites (Upper Namurian В and C) The distinctive feature of the spore assemblage is the dominance of forms whose stratigraphie range is long. They belong mainly in the genera Densosporites and Cristatisporites, beinig represented by several species. Lycospora, Calamospora, Verrucosisporites, Cingulizonates, Crassispora are also abundant. The few species that pass from the lower zones and disappear here are represented by Schulzospora primigenia, S. ocellata, Tripartites cf. сristatus, Reticulatisporites carnosus. A few new species, e. g. Florinites similis, Florinites spp., Radiizonates karczewska, R. difformis, Alatisporites pustulatus, occur in this zone for the first time. Zone V: Florinites spp. (Westphalian A) The lower boundary of this zone is defined by the first more abundant occurrence of specimens of the genus Florinites. Also Lycospora, Calamospora, Cyclogranisporites, Crassispora, Latosporites are amply represented. The upper boundary of the zone is determined by the disappearance of a number of older species, such as Schulzospora rara, Bellispores nitidus, Lycospora noctuina, Sinuspores sinuatus, Ahrensisporites guerickei, Radiizonates karczewska, R. difformis. The stratigraphie range of Radiizonates aligerens coincides with this zone. Due to marked differences between the spore assemblages of the lower and upper parts of zone V, two subzones, Va and Vb, have been distinguished. Subzone Va: Lycospora punctata-pusilla It is a subzone of overwhelming predominance (up to 90%) of the genus Lycospora, due to which the spore assemblage is qualitatively impoverished. The index species for zone V, Radiizonates aligerens and Dictyotriletes bireticulatus, are still very scarce. Subzone VIb: Radiizonates aligerens In this zone the index species is in its prime (acme zone), becoming virtually extinct above it. Single representatives of several species start their development here, but reach their acme only in the higher zones. Zone VI: Endosiporites gldbiformis (Westphalian B) The index species appears here for the first time in abundance. The lower boundary of the zone is established by the disappearance of the species Radiizonates aligerens and simultaneous occurrence of several new species. The upper boundary is defined by the appearance of the species Vestispora fenestrata and Westphalensisporites irregularis. The species Dictyotriletes bireticulatus reaches here its acme. Zone VI has been divided into sulhzones Via and Vlb. Suibzone VIa: Radiizonates faunus-itenuis The lower boundary is defined by the appearance of index species, as well as of a great number of other species such as: Anapiculatisporites spinosus, Cristatisporites indignabundus, Alatisporites trialatus, Vestispora costata, Florinites junior, Potonieisporites sp. The appearance of the species Triąuitrites sculptilis determines the upper boundary of this subzone. Subzone VIb: Triquitrites sculptilis The lower boundary is defined by the appearance of the index species, accompanied by Westphalensisporites clarus and Illinites unicus, while the disappearance of Reinschospora triangularis determines the upper boundary of the subzone in question. Zone VII: Vestispora fenestrata (Westphalian C) The lower boundary is defined by the occurrence of the species Vestispora fenestrata and Westphalensisporits irregularis. They are accompanied by: Triąuitrites arculatus, T. bransoni, Punctatosporites granifer, Torispora sip., Dissaccites sp. There are many species that passed here from the lower horizons, particularly from zone VI. The ranges of all the spore zones in boreholes are given in Tables 2 and 3, along with information regarding the thickness of respective Lithostratigraphic units of the Carboniferous and their extension in the area studied. The spore zones from central-eastern Poland were compared with the microfloral zones of the Lublin and Upper Silesian Carboniferous (Table 4), which had been distinguished earlier in Poland. They were al so compared with the palynologic zones distinguished in some West-European basins (Great Britain, West Germany, France), as well as with the zones established for the Carboniferous of West Europe and West Europe and Poland (Table 5). The above data provides further evidence that the spore method can be used to make chronostratigraphical correlations in the Carboniferous.