Niektóre właściwości budowy i ropo-gazonośności osadów permskich płyty środkowoeuropejskiej

Abstract

SOME FEATURES CONCERNING THE STRUCTURE AND OIL-GAS BEARING PERMIAN DEPOSITS OF THE MIDDLE EUROPEAN PLATESummaryThe lower part of the Lower Permian (Autunnian) has been classified as the orogenic stage when taking into account the forming character, deformation degree and other features. The upper part (Saxonian) is formed as the platform formation and constitutes the basic horizon of the platform cover. Three facies of the Saxonian formation have been isolated: the argillaceous facies situated on the southern bank of the basin, clay and salt-learing facies in its axial portion and along the northern bank. The argillaceous facies is represented on the west forming the eolic deposits, on the east - forming the subaqueous deposits. The regularities of the development of biohermal barrier-type facies of the Stassfurtian formation have been subjected for consideration. One might state their significantly greater thickness and the extent to the south by comparison with those formed on the northern bank of the basin. One might suggest to isolate as the separate stages the Autunnian and Saxonian formations featuring quite different forming character and then to give them the local names within the state boundaries of Poland. Thus in the Saxonian formation one could isolate the clay deposit of the Złotów region and the argillaceous formation of the Środa region. The distribution and features of the Saxonian and Lower Zechstein facies indicate that within the basement of the Middle European Plate one could ascertain the existence of folding of different ages confirming this way the view-points on this matter supported by J. Znosko, S. Bukowy and J. Sokołowski. Basing upon the analysis of facies and thickness of the Permian formations the anticline of the Odra river and the palaeoelevation of the Grudziądz region have been isolated. The gas deposits in the Saxonian formations are closely connected with argillaceous facies and are considered to occur in the regions of the direct occurrence of the Saxonian formations superimposing the coal-bearing Upper Carboniferous series. Within the zone of the vulcanites development of the Autunnian formations the only well-known deposits were those in the vicinity of active abyssal fissures. The gases content largely depends upon the distribution of the Autunnian vulcanites and the Saxonian salt-bearing facies. The most perspective zones have been indicated in the territory of Poland. The prospectings carried on within the main dolomite deposits are extremely complicated because of the epigenetic processes effecting the tectonic activity of the basement. The contours have been put around the perspective zones aiming at prospecting crude-oil deposits occurring within the Ca2.