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Abstract ’J’he texttne characteristics of the Recent sediments in the Hw·~n .. tt u region of the ’ted Sea shelf were investigated and compared with the beach sediments of the same region. The size, sorting and skewness of sediment grains generally decrease with the depth of the sea. The minerals present in the tidal sediments are: Mg-calcite, aragonite, calcite, gypsum, qtlartz and feldspar. The bulk sediments of the shelf zone and some islands, on the other hand, contain mainly aragonite and r·,Ig-cfllci te with occasionally small proportio!lB of quartz and feldspars. Sediment samples from the i!Llrirhc-<”1<-’ zone were analyzed for the elem<’nts: Ca +2 , Mg+_ 2, Sr +2 ; Na + , K+ and total iron. The amounts of carbonate, sulphate, chloride and organic carbon were determined. The distri but :ion of these elements varied with location. Carbonate, calcium, magnesitlrn, organic carbon, strontium, sodium and total iron increase, while sulphate, chloride and potassium decrease from the beach towards the open sea. It is suggested th,tt climatic and- xvii topographic conditions may exert some effect on the process of concentrating these elements from sea water. Sediments of the area are mostly carbonate of marine biogenic origin. A very sm’!ll ftmount of carbonates is of terrestrial origin . At least part of the carbonates have undergone some dirtgenetic changes that resulted in the formation of Mg+? rich carbonates. The bioenvironment is reponsible for the ?recipitation of Sr+2 with calcium carbonate mineral phases. K+ and Na+ in the sedicnents are largly precipitated from sea water. Also, Cl - and so-2 4 are precipitated from sea water in shallow marine zones and in lagoons due to the atid climatic conditions prevailing in the area. |