Architektura i geneza iłów w górnym poziomie węgli brunatnych formacji poznańskiej (środkowy miocen) – odkrywka Tomisławice k. Konina w środkowej Polsce

Abstract

Architecture and origin of clays within the upper part of lignites of the Poznan Formation (Middle Miocene) – the Tomislawice lignite opencast mine near Konin, central Poland. A b s t r a c t. In the Tomislawice opencast mine, owned by the Konin Lignite Mine, a relatively widespread (>1.5 km 2 ) and thick (up to 80 cm) layer of clay occurs within the first mid-Polish lignite seam. These fine grained sediments are interpreted as deposited in a long-lasting lake that existed in the mid-Miocene backswamp area. Due to the exploitation of this seam for electricity production, interbeddings of clastic sediments significantly reduce the quality of lignite. Currently, lignite is mined together with the clays in the Tomislawice opencast mine. Such procedure in extreme cases, where the maximum. thickness of the clay layer is up to 80 cm, increases/may increase the ash content of the entire lignite seam almost twice. Therefore, selective lignite mining would be recommended, i.e. without clays, which unfortunately is not practiced due to technological and financial reasons.