Structural investigations of Monterey kerogen by sequential chemical degradation

► We use successive degradation steps involving Na2Cr2O7/AcOH and RuO4 on kerogen. ► Tetrapyrrole pigments, occur ether- as well as sulfur-bound in the kerogen. ► A scarcely reported series of 2-methyl n-alkanoic acid is identified. ► RuO4 oxidation points to the presence of aryl-alkyl ether groups in the kerogen.