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Ključne besede: silver fir, beech, light response, Carpathians, Dinarides, soil water content, forest
Objavljeno v DiRROS: 02.09.2024; Ogledov: 137; Prenosov: 46
Celotno besedilo (845,78 KB)

Povzetek: The Lower Jurassic Podbukovje Formation represents a succession of shallow marine carbonate rocks deposited on the former Southern Tethyan Megaplatform and one of its successors, the Adriatic Carbonate Platform. Several outcrops of the Podbukovje Formation from central Slovenia (southern margin of the Ljubljana Moor) are presented, bearing possible evidence of Early Jurassic extensional tectonics. Peritidal facies of the lowermost, Hettangian – Sinemurian, part of the Podbukovje Formation locally interfingers with bodies of matrix supported pervasively dolomitized polymictic breccia, several metres to tens of metres thick and is locally cut by neptunian dykes some few decimetres to metres wide. The same or slightly younger part of the formation locally contains grabens/half-grabens metres to tens of metres deep and filled with poorly sorted pervasively dolomitized matrix supported polymictic breccia. Small miliolid foraminifera are present within the clasts and in the matrix. Finally, partly dolomitized blocky breccia tens of metres thick locally overlies the Pliensbachian – lowermost Toarcian limestone with lithiotid bivalves. Besides completely and partly dolomitized clasts, the breccia contains a variety of limestone clasts and preserves common radial ooids and some bioclasts within the partially dolomitized matrix. The Hettangian-Sinemurian breccias and dykes are presumably related to the early, diffused rifting stage of the Penninic (Alpine Tethys) Ocean, whereas Toarcian breccias relate to the main, focused rifting stage. Together with evolving biota and changing paleo-oceanographic conditions, the extensional tectonics may have been an important factor behind the facies changes observed within the Podbukovje Formation
Ključne besede: carbonate platform, External Dinarides, Early Jurassic, Podbukovje Formation, neptunian dyke, breccia
Objavljeno v DiRROS: 09.07.2024; Ogledov: 189; Prenosov: 99
Celotno besedilo (10,26 MB)

Povzetek: Middle Triassic beds exposed along the road between Mišji Dol and Poljane pri Primskovem (Posavje Hills) comprise marlstone, tuff, volcaniclastic sandstone, and thin- to medium-bedded limestone and dolostone. The succession was logged and sampled for conodonts. A relatively rich conodont assemblage was determined, consisting of Budurovignathus gabrielae Kozur, Budurovignathus sp., Cratognathodus kochi (Huckriede), Gladigondolella malayensis Nogami, Gladigondolella tethydis Huckriede, Gladigondolella sp., Neogondolella balkanica Budurov & Stefanov, Neogondolella cf. excentrica Budurov & Stefanov, Neogondolella constricta (Mosher & Clark), Neogondolella cornuta Budurov & Stefanov,Neogondolella sp., Paragondolella excelsa Mosher, Paragondolella liebermani (Kovacs & Kozur), Paragondolella trammeri (K o z u r), Paragondolella cf. alpina (Kozur & Mostler), and Paragondolella sp. The assemblage correlates with the upper Anisian and lowermost Ladinian assemblages from the Global Boundary Stratotype Section and Point (GSSP) of the Ladinian at Bagolino in the Southern Alps in northern Italy. Along with conodonts, numerous specimens of benthic foraminifera Nodobacularia? vujisici Urošević & Gaździcki were recovered from the lowermost part of the succession. Previous research on this taxon is critically evaluated.
Ključne besede: Dinarides, Sava Folds, Middle Triassic, upper Anisian, lower Ladinian, basin, volcaniclastics, conodonts, foraminifera
Objavljeno v DiRROS: 15.01.2024; Ogledov: 441; Prenosov: 132
Celotno besedilo (11,54 MB)

Povzetek: The study focused on the post-Middle-Miocene stress analysis within the dextral strike-slip zone of the Dinaric fault system in the collision zone between the European plate, the Adria microplate and the Pannonian Domain. Block rotations were studied by re-examination of available paleostress data and their spatial distribution. The results are in agreement with the existing block model of the area, indicating CCW rotations within blocks between the main strike-slip faults in which rotation angle increases from W to E. The improved kinematic model, which is proposed in this study, will contribute to the knowledge on the kinematics within the complex collision zones and improve the seismic hazard models.
Ključne besede: collision zone, NW External Dinarides, Southern Alps, paleostress tensor, strike-slip zone, block rotation
Objavljeno v DiRROS: 06.07.2023; Ogledov: 602; Prenosov: 236
Celotno besedilo (8,47 MB)

Povzetek: Comprehensive glacial Quaternary studies involving geochronological methods, modelling of ice topography with the support of field geomorphological and geological data in the Balkan Peninsula are relatively scarce, although there is evidence of past glaciations in several mountain ranges. Here, we present research on the extent and timing of past glaciations on the northern Velebit Mt. in coastal Croatia and inferences of the climate during that time. Based on geomorphological and sedimentological evidence and using cosmogenic 36Cl surface exposure dating of moraine boulders, we provide an empirical reconstruction of past glaciers and compare this with the Parallel Ice Sheet Model (PISM) simulations under different palaeoclimate forcings. The dating results show that the northern Velebit glaciers reached their maximum extent during the last glacial cycle before the global Last Glacial Maximum (LGM). Maximum ice extent likely correlates with Marine Isotope Stage 5–4, although the exact timing cannot be determined at this point due to poorly known site- and time-specific denudation rates. Empirical reconstruction of the maximum extent suggests that the area covered by glaciers was ~116 km2. The-best fit PISM simulation indicates that the most likely palaeoclimate scenario for the glaciers of this size to form is a cooling of ~8 °C and a 10% reduction in precipitation from present-day levels. However, the best-fit simulation does not correctly model all mapped ice margins when changes in climatological parameters are applied uniformly across the model domain, potentially reflecting a different palaeoprecipitation pattern to today.
Ključne besede: Pleistocene, cosmogenic isotopes, glacial geomorphology, Dinarides, PISM
Objavljeno v DiRROS: 04.03.2022; Ogledov: 894; Prenosov: 342
Celotno besedilo (14,52 MB)