Stratygrafia sadów kajpru w profilu wiertniczym Boża Wola na podstawie badań sporowo-pyłkowych

Abstract

STRATIGRAPHY OF KEUPER DEPOSITS FROM BORE HOLE BOŻA WOLA ON THE BASIS OF SPORE-AND-POLLEN ANALYSISSummaryThe article presents the results of spore-and-pollen analysis of the Keuper deposits drilled at Boża Wola, within the north-eastern margin of the Świętokrzyskie Mts. The examinations allwed the stratigraphy of the above deposits to be determined. These deposits are variously intepreted in the literature (H. Jurkiewkz, 1965, 1972; H. Senkowiczowa, 1966) from both lithostratigraphic and tectonic points of view.The palynological stratigraphy has been established on the basis of three characteristic spore-and-pollen assemblages, distinguished in the microfloristic picture of the deposits examined (Fig. 1).The first (I) spore-and-pollen assemblage has been distinguished at a depth of 1571 ,0-161 6,0 m. Here predominate spores of the genus Aratrisporites (L e s c h.) P l a y f. et D e t t m. (41% on the average), represented by the species A. fimbriatus, A. granulatus, A. coryliseminis, A. paraspinosus, A. flexibilis, and spores of the genus Todisporites C. o u p. (29% on the average) represented by the species T. cinctus, T. minor, T. fissus, pollen grains Minutosaccus potoniei M ¬ d l e r, M. schizeatus M ¬ d l e r and others. Compared with the spore-and-pollen assemblages worked out from the western and central areas of Poland, and with those discussed in the literature, this assemblage allows the age of the deposits considered to be determined as Lower Keuper.The second (II) spore-and-pollen assemblage has been found to occur at a depth of 1535,0–1547,0 m (Fig. 1). Here, the pollen grains of the genus Ovalipollis W. K r. predominate (35% on the average) of Ellipsovelatisporites plicatus K l a u s, Eucommiidites sulechoviensis .0 r ł., Echinitosporites iliacoides. W. K r. et E. S c h. A comparison with the spore-and-pollen assemblages, already known from the western and central parts of Poland, allows the age of the deposits with this assemblage to be determined as that ranging from the top part of the Lower Keuper, i.e. from the Boundary Dolomite, to the Lower Gypsum Series of the Upper Keuper, inclusive. At a depth of 1398,7–1535,0 m no sporomorphs have been encountered in the dolomitic-marly series here.Higher up, at a depth of 1365,0–1398,7 m, the first (I) assemblage has been distinguished once again, showing the presence of the deposits of Lower Keuper age. This proves the conception by H. Jurkiewicz (1965, 1972) as to the twofold appearance of the Lower Keuper deposits due to a fault existing in this area (Tab. 1).Moreover, at a depth of 1313,0–1345,0 m, the second (II) spore- and-pollen assemblage appears anew, and permits the age of the deposits to be determined as that ranging from the Boundary Dolomite to the Lower gypsum series, inclusive.After a gap of about hundred metres, from 1212,0 m to 1218,0 m characterized by a lack of any sporomorphs, a third (III) spare-and-pollen assemblage has been encountered. Of particular significance are here, beside the pollen grains of the genus Ovalipollis, the sporomorphs Aulisporites astigmosus (L e s c h.) K l a u s (55%), which appear to be index forms of the Reed Sandstone deposits.