The detailed composition of a shale oil was determined using a novel comprehensive 2D gas chromatographic (GC x GC) method, extending the method of Dijkmans et al. (2014). Four different detectors (flame ionization detector (FID), sulfur chemiluminescence detector (SCD), nitrogen chemiluminescence detector (NCD) and time of flight mass spectrometer (TOF-MS)) mounted on different GC x GC's were used. The use of two internal standards; 2-chloropyridine and 3-chlorothiophene; allowed quantification of the shale oil's composition by carbon number and by structural class. 20 different classes were detected in the shale oil: paraffins, isoparaffins, olefins/mononaphthenes, dinaphthenes, monoaromatics, naphthenoaromatics, diaromatics, naphthenodiaromatics, triaromatics, thiols/sulfides, benzothiophenes, naphtenobenzothiophenes, dibenzothiophenes, pyridines, anilines, quinolines, indoles, acridines, carbazoles and phenols. A significant amount of sulfur and nitrogen containing compounds, 2.2 wt% and 4.2 wt% respectively, were detected. (C) 2014 Elsevier Ltd. All rights reserved.