FSUE VNIIOkeangeologia named after I. S. Gramberg:

I. A. Egorov, Leading Researcher, Candidate of Geographical Sciences, e-mail: ieg@mail.ru

FSUSPE «Polar Marine Geosurvey Expedition»:

I. G. Dobretsova, First Categogy Mineralogist

The study of the sediments in the general scheme for studying the rift zones and for searching the polymetallic sulphides (as a particular problem) performs both scientific and practical functions. The study of sediment samples schlichs allows to estimate the area availability for sulphide prospecting, to determine the distance to a source and the type of ore facility. In addition, the schlich analysis is helpful in mapping the area, covered by bottom sediments. The presence of the tracer minerals of hydrothermal activity, even single units, may indicate the proximity of the ore source. The results of the schliches-mineralogical analysis are derived directly in the cruise. These results help to adjust the direction of searchings and, with maximum efficiency, locate the prospective areas for discovering the hydrothermal sites. Determination of the optimal samplind density is the main task for sediment sampling for schlich-mineralogical analysis. The choice of the points for sampling stations is proposed to determine, using the capabilities of GIS analysis of the bottom surface. This method allows to calculate the closed lithodynamic systems of relief. Lower extremes of systems are the places of maximum accumulation of loose material or the whole closed area. System determination of precipitations` sampling density, allows to consider this method as a full schlich survey in deep-water conditions of rift zones.

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