PALEOGEOTHERMAL GRADIENT IN THE BOSKOVICE FURROW

A coalification data set from the first seam of the Rosice-Oslavany co al district in the Boskovice furrow was used to estimate the temperatu re gradient prevailing within the furrow during Autunian sedimentation . An appreciable scatter of the data reflects the complicated history of the sedimentary region. The northern part of the district displays a higher degree of coalification. The results of the evaluation sugges t that the region ceased to subside in the upper Autunian, and that th e extent of the post-Autunian erosion does not exceed 500 metres. This version of the burial history, which is consistent with geological da ta, yields a temperature paleogradient of 76 mK/m for the northern par t and of 72 mK/m for the southern part of the district. The gradients estimated are higher than those prevailing during the Carboniferous se dimentation in the Central Bohemian Basin (45 - 53 mK/m), lower than v alues found for the Ostrava Formation in the Upper Silesian Basin duri ng its Namurian A sedimentation (about 95 mK/m), but comparable with v alues evaluated for the Karvina Formation of the same basin deposited during the Namurian B - C and Westphalian A (60 - 77 mK/m).