AUTHORS: R.Di Cuia, A.Criscenti, R.Bitonte, S.Borello, G.Gattolin, A.Riva, S.Farner, R.Konert, E.McAllister
AAPG Confernce, Naples (Italy), March 2014
The Berati zone is one of the tectonic units of the western Albanides in southern Albania. In this area three main structures have been studied in outcrop: the Shpirag, the Molishti and the Gyrokaster Gjirokaster anticlines. These structures are made of Jurassic to Eocene carbonate basinal sequences deposited in the Ionian basin.
The structures were studied to understand their geometry and their kinematic evolution during the last tectonic phase that affected the area and produced the Albanides thrust belt. The study was based on the acquisition of structural data acquired over the two structures on the frontlimb, backlimb and hinge of the two anticlines and on the interpretation of high resolution satellite images.
The Sphirag and Molishti anticlines have steep limbs and a relatively flat top. Fractures are preferentially oriented parallel to the axis of the structures on the top of the anticlines while the limbs show a characteristic conjugate sets of fractures consistent with a maximum horizontal stress orthogonal to the axis of the structure. Long lineaments cross cut the anticlines with an orientation orthogonal to the axes. Intense parasitic folding is present mainly of in the limbs of the anticlines.
The northern part of the Gyrokaster Gjirokaster structure has a different geometry and shows a different fault and fracture network organisation. The structure is made of two stacked thrust sheets with the lower most part of the structure made of a recumbent anticline.
The integration of the detailed structural data acquired in the field, the regional interpretation of lineaments, the earthquake focal mechanisms and sedimentological analysis of the carbonate sequences involved in the deformation highlight that the folding style, the detachment zones, the density and geometrical characteristics of fractures are controlled by lithology, texture and geometry of the carbonate sequences