Tectonic evolution and hydrocarbon potential of the southern Moesian platform and Balkan-Forebalken regions of northern Bulgaria

Conference · Wed Sep 01 04:00:00 EDT 1993 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:6917134

Emery, M ^[1]; Georgiev, G ^[2]

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1. Maxus Energy Corp., Dallas, TX (United States)
2. Univ. of Sofia (Bulgaria)

The major tectonic elements of northern Bulgaria are the east-west-trending Balkan-Forebalkan fold belt and the Moesian platform. Moderate hydrocarbon exploration potential exists in trapping geometries generated during the tectonic evolution of the region coupled with reservoir/seal pairs and source rocks within Mesozoic strata. The tectonic evolution of the region includes Early Triassic to Early Jurassic intracratonic rifting followed by multiphase compression that contracted the rift basin and produced a north vergent fold and thrust belt along the southern margin of the stable Moesian platform. Compression began during the Early Cretaceous, continued during the Paleocene, and concluded during the middle Eocene. Trap types generated during the tectonic evolution include normal fault-bounded rotated blocks in the autochthonous section and elongate, asymmetric anticlines in the allochthonous section. Triassic to Upper Jurassic Marine facies were deposited in an east-west-trending rift. Sediments deposited in a shallow foredeep, which evolved during Lower cretaceous compression, overlay the rift sequence. The Early Mesozoic rift sequence provides the depositional settings for Middle Triassic and lower Middle Jurassic source rock shales and sandstone/carbonate reservoirs ranging from Middle Triassic to Lower Cretaceous. Carbonate reservoirs generally are porous dolomites with intercrystalline, moldic, and vugular pore types interbedded with nonporous limestones. Clastic reservoirs are quartz-rich sandstones with pore types that are reduced intergranular, dissolution, and microporosity. These heterogeneous reservoir targets exhibit poor to good reservoir characteristics and are overlain with sealing lithologies of variable thicknesses.

• OSTI ID: 6917134
• Report Number(s): CONF-9310237--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Journal Volume: 77:9
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
ANTICLINES
BULGARIA
CARBON COMPOUNDS
CARBONATES
CENOZOIC ERA
DEPOSITION
DEVELOPING COUNTRIES
EASTERN EUROPE
EUROPE
EXPLORATION
GEOLOGIC AGES
GEOLOGIC STRATA
GEOLOGIC STRUCTURES
GEOLOGIC TRAPS
GEOLOGY
GEOMETRY
HYDROCARBONS
JURASSIC PERIOD
LITHOLOGY
MATHEMATICS
MESOZOIC ERA
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PETROLOGY
RESERVOIR ROCK
RESOURCE POTENTIAL
RIFT ZONES
ROCKS
SANDSTONES
SEALS
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEDIMENTS
SHALES
SOURCE ROCKS
TECTONICS
TERTIARY PERIOD