Abstract
The Bulgarian part of the western shelf of the Black Sea corresponds to a part of the passive margin of the Bulgarian continental microplate towards the transition ú with the Black Sea oceanic microplate. It is probably the only preserved fragment of the passive margin of the Black Sea Gulf of the Tethys Paleocean. The inner (coastal) and outer (seaside) shelf sections are distinctly beached, separated by a shelf slope. A significant difference in the regional morpho-structural situation was found for the two parts of the shelf. On the inner (coastal) shelf, antiforms and synforms are few in number and of impressive size. In contrast, small, short, numerous antiforms and synforms are observed in the outer part of the shelf. The orientation of all morphostructures corresponds to the general direction of the shelf, which in the northern part of the studied area is south-southwest - north-northeast. At the parallel of Burgas Bay, the direction of the shelf changes from north-northeast to south-southeast. The location of the alteration is associated with a bundle of transverse faults. The influence in these two parts of the shelf, respectively the Bulgarian continental microplate from the north and the Strange continental microfragment from the south, is obvious.