The organic rich sediments (coals and coaly shales) record particular events in the delta plain sedimentation history. Reconstructing their depositional environment gives palaeoecological and sedimentological information permitting the use of these coals and shales as regional isochronous markers. There is a wide variety of diagrams used for reconstructing the depositional settings of coals and coaly shares. They all are based on two types of petrographic analysis, rarely used in combination: maceral and microlithotype analyses. This synthesis work is based on a large number of combined analyses (575 samples) and takes into account the sedimentologic and sequential context. We propose an updating of the most commonly used diagrams, as well as the guides to their interpretation and give the example of a regional study of the Brent Group fluvial-deltaic series (Mid Jurassic, North Sea).