The Sakar and Strandzha Mountains are disposed in the South-East end of the Balkan Peninsula (on the both sides of the Bulgarian-Turkish boundary). They belong to the southeastern margin of the Bulgarian continental microplate. They are limit from North Thracian morphostructural zone to the North, the East Thracian morphostructural zone to the South and the Rhodopean morphostructural zone to the West. The observed mountain territory builds the Sakar-Strandzha morphostructural zone. It is divided by Sakar Dervent and Strandzha morphostructural areas. Every of them include morphostructural regions. They are composed by numerous Late Pleistocene-Holocene dome-like morphostructures. The relics from the Post Early Pleistocene concentric morphostructures are distributed in the entire zone. They were determined some archer and concentric Holocene mountain morphostructures.
The regional seismic activity (during the last 50 years) outlines three parts of the Sakar-Strandzha morphostructural zone. The western one - the Sakar part is moderate seismic active. The centred - Dervent part is practically seismic „calm“. The eastern one- Strandzha part show a very intensive seismicity. It can by given right in a future (after the necessary investigations) to divide the zone in three areas.
The article introduces the results of the author’s new investigations about the origin, Quaternary morphotectonic evolution and the modern morphostructure of the Bulgarian Continental Microplate in the eastern part of Balkan Peninsula. The research was realized on a base of the contemporary Plate tectonic study principia by means of the morphostructural analysis apply. It was provided the principal relief building role of the regional mosaic pattern and the listric faulting in the Balkan Peninsula East Part.
The Black Sea Neozoic passive continental margin marks the natural „bridge” between the Moesian and Bulgarian continental microplates and the Black Sea oceanic microplatte. It was coming in to being after the saturation between the terrains which are composed the Neo Europe south east part during the Early Paleogene. The subaerial part of the margin includes the most east parts of the South Moesian, Hemus, and Upper Thracian and Sakar-Strandzha morphostructural zones. The subaquatic part of the margin is composed by the consequently orderly step lower to the Black Sea bottom: high shelf zone, lover shelf zone, continental slope and continental foot. The Black Sea Neozoic passive continental margin is characterized by low seismic activity. It is concentrated in some fault zones.
The East Balkan Peninsula Area was a part from the Tethys Ocean until 72 000 000 years. The pre Maestrichtian geologic-tectonic pattern of cockle of the East Balkan Peninsula Area wasn’t built on the Europe Continental Massif. The modern East Balkan Peninsula Relief is forming during the Late Quaternary time. The East Balkan Peninsula Margin coincides with the border between the Bulgarian and Moesian Continental Microplates from the west and the Black Sea Oceanic Microplatte to the east. This border present the Neo Europe West Passive Continental Margin in the area of the last Tethys Oceanic Fragment – it Black Sea Oceanic Gulf.