Systematics of pyrolytic gas (N2, CH4) liberation from sedimentary rocks: Contribution of organic and inorganic rock constituents

► The pyrolytic liberation of N2 and CH4 from sedimentary rocks was investigated. ► Measurements were performed on samples from different depositional environments. ► Samples varied in organic matter content and thermal maturity level (rank). ► N2 pyrograms reflect varying proportions of organic and inorganic nitrogen moieties. ► A classification scheme of five characteristic N2 liberation patterns is proposed.