Evelin Marinov¹, George Ajdanlijsky²

(1) Kanisko Ltd, Sofia, Bulgaria
(2) University of Mining and Geology, Sofia, Bulgaria

ABSTRACT: Geological Structure and Hydrocarbon Potential of the Central Balkanides, Bulgaria

Using significant volume of field, wells and seismic data, a new complex model for the geological structure and evolution of the Central Balkanides area is proposed. The hydrocarbon potential of the region critically is evaluated. The Triassic and Lower-Middle Jurassic rocks in Central Balkanides are similar to the deposits of same age in Moesian plate. Through the Mesozoic Forebalkan have been relatively narrow depression, while Stara Planina and Moesian plate were respectively its southern and northern platform margins - South Moesian rift. During the Old-Cimmerian phase closing of the basin have began. During the Austrian phase the southern board of the rift have been thrusted over the Forebalkan and Moesian plate. The Illyrian tectonic phase marked the last thrusting northwards. In the Central Balkanides, petroleum shows are established into the carbonate rocks with Middle-Upper Triassic age and in Early-Middle Jurassic sandstones as well. Shows are connected mainly with the thrust surfaces. The hydrocarbon potential of the source rocks has been realized. The Middle Triassic limestones and dolomites are the best reservoir. Clay-carbonate Ladinian-Carnian sediments and the granites of Sredna Gora allochthon are their seal. Structural multilevel traps in Triassic and Lower-Middle Jurassic deposits, south of Chiflik village and under the Teteven allochthon might be expected. Structural, tectonic screening traps are expected in the Mesozoic deposits, buried under the Sredna Gora allochthon. Taking into consideration the specificity of the migration and accumulation of hydrocarbons in the thrust zones the regions of towns Karlovo and Kazanlak are estimated as the most prospective areas.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado