Organic matter distribution in the modern sediments of the Pearl River Estuary

► We quantified biomarker concentrations in surface sediments from the Pearl River Estuary. ► We utilised four concentration ratios, based on n-alcohols, fatty acids, sterols and GDGTs. ► All four ratios recorded a decrease in terrestrial organic matter from river to sea. ► The ratios were consistent with the sedimentary regime. ► Biomarker-derived temperatures suggest an uplands sediment source.