In my diploma thesis I mapped the southern Vipava Valley, SW Slovenia. The area is geotectonically a part of the External Dinarides. The oldest rocks in the area outcrop in the limestone cliffs of Mt Nanos. These limestones are bioclastic, algal-foraminiferous-bioclastic and rudist limestones of Campanian and Maastrichtian age. Structurally they belong to the Hrušica Nappe which is thrusted over Eocene flysch strata. Liburnian formation, outcropping in the southern most part of the study area, is of Maastrichtian and Paleocene age. Bituminnous limestones of Vreme facies underlie the basal conglomerate and breccia which pass upward into Eocene flysch strata. Flysch comprises a sequence of alternating sandstone, mudstone, marlstone and calciturbidites. The latter are mostly calciturbidites composed of limestone breccia or conglomerate in the base, calcarenite in between and marlstone on top. Paleographically, this area was part of the Dinaric Carbonate Platform in the late Cretaceous and early Paleogene, which drowned in Eocene due to the formation of forland basin and was buried by flysch sediments. The youngest deposits in the area are Quarternary scree material with clasts of Cretaceous limestone and flysch sandstone which are partly cemented into breccia. These sediments originated from erosion and gravitational flows of the SW slopes of Nanos. The area constitutes three tectonic units. On the NE, the Cretaceous limestones of the Hrušica Nappe are thrusted over eocen flysch strata of Snežnik Nappe, and these are overthrusted onto Eocene layers of Komen Thrust-sheet. The beds generally dip towards NE at variant angles, from 40° to 80°. One stronger Dinaric-oriented deformation zone passes the area. According to some authors, this is a fault-zone of the Vipava Fault, but since I didn't found any evidence of its existence, it could be interpreted as the thrust zone of Snežnik Nappe.
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