Evidence for submarine groundwater discharge on the Southwestern shelf of Taiwan

► The study is aimed at identifying the locations of SGD by means of routine oceanographic measurements. ► At SGD locations, there was a 0.009 to 0.105 psu drop of salinity in the lowermost 0.1-2.1 m layer. ► SGD resulted in local maxima of dissolved substances and minima of turbidity. ► N-alkane composition of sediments at SGD sites resembled that of the groundwater taken from a well. ► The groundwater seepage rates estimated from advection-diffusion balance were 1 to 10 cm day−1.