Abstract: This paperpresents a study ofthe 17 meters high Harmantaşı submarine hill, located 1 mile offshore and at 30meters depth in the north ofthe Saros Gulf, the underwaterspringssurfacing there and theirimpact on seawaterandsediments. Forthispurpose water andsedimentsampleswere taken along lines, and temperature, salinity, pH,DO and organic carbon, total carbonate and heavy metals (Fe, Mn, Cu, Ni, Zn) were analyzed. Also theforaminifertypes were determined.Atsome specificpoints along the 4 linesstudied, underwaterfreshwatersprings arefoundwith the help ofanalyzedwater parameters. The measurement depth being between surface water and mid depth water, and the cyclecurrents having different directions and speeds on the surface, mid and bottom levels, effect the spreading speedanddirection ofthefreshwater.Organic carbon content in surface sedimentsamplesfrom 4 lines, is at acceptable varies between 0,5%-2%. In 41ofthe samples, CaCO3 is measured between 6%-83% and the average is 44%. Especially intensive shell existencein the stations close to the center caused higher concentrations of CaCO3 However at the lower parts ofthesubmarine hill the source ofCaCO3 is more lithogenic. In the stations where an increase in CaCOs isfound, there isa decrease in organic carbon content. Also in the samples with high carbonate contents, sand-sized grainsfromshells are abundant, whereasin the stations with dominant mudsizedgrainsthe organic carbon contents are high.Metal concentrations match well with the average compositions ofsedimentary rocks. General distribution ofthe5measured heavy metals (Cu, Zn, Ni, Mn, Fe) are supporting each other. There is metal increase in some ofthe 42samples studied (for example 1-30, 11-30, IV-70). Whereas, when each metal is elevated within itself, pointaldifferences are clear (for example: in the station 1-60, Ni high, Zn low concentration). Metal contents ofthenorthwestern part ofthe Harmantaşı submarine hill are relatively higher when compared with those from thenortheastern part. Changes in the submarine hill`s morphology are reflected in abundant occurrences ofshelledorganisms at some stations, and differences in speed and direction of currents, influence the accumulation ofinorganic sediments, which determinesthe heavymetal concentration.From the foraminifer species, CaCOt shelled Haurenid types exist abundantly in spring centers and nearby.Farther away, aglutinantshelltextulariidforms are increased.