Hydropyrolysis is a newly-developed technique used to set free small molecular from macromolecular of organic matters by covalented-bond cracking.Our study has been focused on the possibility of employing the technique in extracting primary organic matters from highly mature hydrocarbon source rocks.The Lower Palaeozoic source rocks of four sedimentary facies in Tarim basin were selected to run the hydropyrolysis experiments.The results show that molecular compositions of hydropyrolysis products(n-alkanes and steranes) from kerogens match well with that of the selected source rocks

proving that the technique works effectively in extraction of primary organic matters from highly mature hydrocarbon source rocks.The study paves the way for further application of the technique to oilsource correlation.