The Structural Features and New Exploration Concepts in the Ionian Zone of Albania
VELAJ, TELO K.
1700 Street Rd Apt. S-4, Warrington, PA 18976
The main structural features of the Ionian zone are: intensive folding, much developed disjunctive tectonics, considerable overthrusts, diapirism development etc. The stratigraphic section consists of evaporates (T3 ), carbonates (T3-Pg2 ) and flysch-flyschoides (Pg3-Langian), which are in imbrications and duplex system as well.
The most oilfields discovered in Albania extend in the Ionian zone in carbonate section (Cr2- Pg2 ) in the anticline structures delivered by thrusting of adjacent structures.
Three anticlinal belts (Berati, Kurveleshi, and Cika) extend into the Ionian zone, with SE-NW trend according to western orogen front. The main characteristic of these belts is the thrusting westward estimated to be in the range of 20-30 km. The phenomenon of backthrust (4-6km.) is frequently developed in the eastern flanks of the units. The thrusting processes are helped by the thickness of Upper Triassic evaporite (major decollement level) which have erupted through the fault planes. This large scale thrusting and backthrusting encroach upon and cover adjacent structures forming potential new hydrocarbon prospects in subthrust complexes.
The thrusting of the units exists only in the Kurveleshi belt with amplitudes of 8-10 km. In this belt two oilfields are located in buried duplexes, beneath the Mali Gjere and Kremenara thrusts.
In the Berati belt the structural lines are not thrusted. The perspective sector is only in the western side in a subthrust complex. The presence of a large anticline (Dumrea), directly north to its northern arch, its continuation southward (Spiragu oilfield) under the belt, depicted by drilling and seismic data and the presence of the surface anticline structural line (Kurenton-Kasidhiaris) at the southern arch in Greece, show a structural line with extension and high prospective.