We investigated the nannoflora of the Berzsek Marl Formation and the Labatlan Sandstone Formation from the sequence of the Berzsek Hill at Labatlan. The nannoplankton investigations show that the portion of the Berzsek Marl exposed on the surface is not older than the Lower Aptian. The uppermost part of the Labatlan Sandstone overlying the Berzsek Marl can be correlated with the lower part of the Upper Albian substage.