Novel geochemical proxies derived from 1D simulation of Liaohe oil sand bitumen to monitor in-situ combustion process

•1D in-situ combustion (ISC) simulation has performed on core from heavy oil reservoir.•Concentrations of saturated and aromatic hydrocarbons behavior regularly in ISC zones.•Molecular parameters based on degree of isomerization are insensitive to ISC process.•Geochemical proxies derived from degree of thermal cracking can monitor ISC process.•Occurrence of anthracene and benzo[a]anthracene is supplementary evidence of ISC.