Paleogen z wiercenia Szczecin IG-1 w świetle analizy sporowo-pyłkowej

Abstract

PALAEOGENE IN BORE BOLE SZCZECIN IG-1 IN THE LIGHT OF SPORE-AND-POLLEN ANALYSISSummaryThe present paper deals with some spore-and-pollen assemblages of Palaeogene age, elaborated on Palynological evidences obtained from the deposits encountered in the bore hole Szczecin IG-l. The assemblages of the Paleocene and Eocene are here for the first time described from the area of Poland, and a newly discovered site of Middle Oligocene deposits is discussed.The age determined by means of spore-and-pollen analysis can be presented as follows:1 – Upper Paleocene (329,0–353,0 m) is developed as coaly clays that contain rich sporomorphs such as Trudopollis subhercynicus, T. with feeble oculus, Tricolporopollenites of the group edmundi/satzveyensis, Nudopollis, and in lesser quantities such small forms as Tricolpopollenites liblarensis liblarensis, T. liblarensis fallax, Tricolporopollenites cingulum pusillus, T. cingulum oviformis and others. Spores and sporomorphs of Pityosporites are here rarely found.This assemblage was compared with a spore-and-pollen picture from Antweile (W. Thomson, H. Pflug, 1962) and, according to similar features, was determined to be of Upper Paleocene age.2  Lower-Middle Eocene (313,8–328,0 m) occurs here as a brown coal seam that contains a number of sporomorphs: small colporate sporomorphs, colporate sporomorphs, as well as Monocolpopollenites tranquillus, Inaperturopollenites dubius and others. Forms, typical of the Upper Paleocene mentioned above appear sporadically; more frequently are found spores and, as before, slight amounts of pollen grains of Pityosporites type.Fig. 4 illustrates the percentage content of pollen grains of various plant groups that followed each other and formed the coal seam investigated. On the basis of the comparison with the results obtained in Germany, the deposits that contain this assemblage of sporomorphs are placed between the Middle Eocene deposits from Geiseltal (R. Potonie, 1934, W. Krutzsch, 1959, 1961) and the lower seam from Helmstedt, referred to the Lower Eocene (H. Pflug, 1952).3 – Upper Eocene (?) 220,0–299,0 m) is developed as grey green clays. Sporomorphs appear here only in some samples. Of colpate sporomorphs and colporate sporomorphs, numerous in the Lower-Middle Eocene, only Tricolpopollenites liblarensis liblarensis and Tricolporopollenites cingulum pusillus are found in greater number. Forms, typical of older Paleocene, except for Trudopollis subhercynicus, are almost absent. On the other hand, the sporomorphs of Pityosporites type increase.This assemblage was compared with the palynological  pictures from Borken (W. Krutzsch,1961, 1965) and Burghasungen (F. Mürriger and H. Pflug, 1951) which are referred to the upper part of the Middle Eocene and, as a younger one, was related with the Upper Eocene.4 – Middle Oligocene is developed as grey-green and brown clays. Sporomorphs appear at a depth of 179,0–l85,0 m only; among them Inaperturopollenites dubius, Tricolpopollenites liblarensis liblarensis, Tricolporopolollenites cingulum pusillus, Pityosporites, and sporadically – Inaperturopollenites emmaensis and Cicatricosisporites dorogensis are numerous. The last named spore is, in the Middle Oligocene deposits, of the greatest vertical extent. The assemblage, here considered is similar to that found in the Middle Oligocene deposits from Gorzów Wielkopolski and in the Toruń clays (I. Grabowska, 1965).