Abstract: In the framework of the Carboniferous investigationscarried out by the M.T.A.E. in the Zonguldak coal basin since 1946,some reports ,and publications were issued, dealing vith Carboniferous ,and with the Cretaceous cover thereof. A summary of these observations is contained in this article, in which special attention is paid to theexpected depth of the Carboniferous which is expressed in a contourmap, which shows the influence of the tectonics since the beginning ofthe Cretaceous sedimentation in the surface of the Carboniferous. Thetectonical structure of the Carboniferous is broadly outlined in the text.