The effect of Darnó Belt on the Miocene Borsod coal-bearing succession

Abstract

In this paper the effect of the Darnó Deformation Beit on the Miocéné coal-bearing layers in Borsod
county is presented based on sequence stratigraphical assessment on log data of selected boreholes.
The effects of the former syn-tectonic and post-tectonic movements along the Darnó Fault Zone are
proved. Gradual changes in the sequences refer to syn-tectonic movements, where the reason of these
changes is the higher rate of subsidence of the Darnó Beit compared to the Eastern part of the basin. The
main evidences of the gradual changes are the following: the scissors like opening of eastern Borsod
lowest, fifth lignité layer into the western Borsod three lignité layers; the thickening of the fifth lignité
layer, and of the sequences between the fifth and fourth lignité layers towards western direction; the
narrowing of the fourth lignité layer towards western direction due to the former marine transgression.
The post-tectonic effects are manifested by normál faults. Usually these normál faults cause variations in
the thickness of parasequences. The sharp boundary of the two different basin parts on the right side of
the Sajó River refers to lateral movements.