Migration features of crude oil in fluvial deposits of Maling oilfield in Ordos Basin, China

► Oils in the Maling oilfield are genetically related and of similar maturity. ► Pyrrolic N compounds are consistent with migration inferred from regional geology. ► Fluid inclusion homogenization temperatures indicate two stages of oil accumulation. ► Migration pathways were likely the sandstones of multi-branched river channels. ► Vertical migration driven by capillary pressure and overpressure.