A suite of 68 surface sediment samples from the South Evvoikos (SEG), North Petalion (NPG) and South Petalion (SPG) gulfs was analysed for grain size, mineralogy, major and minor elements in the bulk sample and the < 2 mu m fraction. Grain size analysis distinguished two sedimentary provinces: i) SEG with fine grained sediments; and ii) NPG, SPG dominated by relict sandy sediments. Abundant minerals are quartz, feldspars, calcite and Mg-calcite. Heavy minerals identified were epidote, hornblende, zircon and glaucophane. Factor analysis revealed that chemical elements of the total sample are mainly of terrigenous origin, supplied by the Asopos river, which discharges in SEC. The southern part is dominated by residual Si and biogenic components. Metals are generally present in low concentrations. I-geo index computation for the trace elements indicated relatively high concentrations of Ni and Cr in the SEG area, which are in all probability related to the erosion of laterite formations and ultramafic rocks.