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Relevance of the work. According to current ideas and forecasts, the southern margins of the Pre-Caspian basin combines carbon-bearing massifs stretching from Astrakhan-Imashevsky elevation in the west to the South Embinsky one in the east. Within the margins, some large Paleozoic elevations associated with the carbonate development zones (the Kultuk Morskoy zone) have been identified with the help of geological and seismic methods. The determination of the structure of the carbonates zone of the southern margins in comparison with counterparts in the structures of adjacent areas of the earth (Karaton-Tengizsky bar and the South Embinsky elevation) poses the task of more detailed study for setting up prospecting drilling. Purpose of the paper is to substantiate the high prospects of local elevations of the Kultuk Morskaya zone in the Paleozoic complex, taking into account the use of the results of methods integration (seismic, airborne magnetic survey and gravity prospecting) obtained in recent years (2009-2013). Research methodology: comparative analysis of seismic data, anomalous magnetic field and gravity anomalies, including deep hole drilling data for recent years. Results. Taking into account the current understanding of the distribution of carbonate massifs, including the water area of the Northern Caspian, the structure of the southern border in the latitude band closer to the border with the Ustyurt-Bozashinsky basin was specified. The author gives a comparative analysis of the structure and development of carbonate deposits in the uplift areas of the South, Southwestern periclinal of the South Embinsky elevation and the Kultuk Morskoy zone, uniting the local structures of Sarytau, Burynshik, Burynshik Vostochny and Ostrovnaya. The justifying factors concerning the structural and tectonic unity of these areas are given. Based on the previously obtained results of prospecting works, lithofacial margins of the sludging basin in the southern border of the Caspian basin were justified; they are represented by carbonate massifs (Astrakhan-Imashevsky, Zhambai, Zhambai-More, Kultuk Morskoy, Yuzhnoye and South-Western periklinal of the South Embinsky elevation). Conclusions. Within the Kultuk Morskoy zone, taking into account the combination of data and features of the anomalous magnetic field and gravimetric anomalies, the high prospects of local structures of Sarytau, Burynshik, Burynshik Vostochny and Ostrovnaya are justified. On this basis, a forecast for the development of carbonates was made in the context of these structures, which in turn is based on favorable geological-geophysical, structural-tectonic and probable geoecological prerequisites.