The Julian Alps are located in NW Slovenia and structurally belong to the Julian Nappe where the Southern Alps intersect with the Dinarides. In the Jurassic, the area was a part of the southern ...Tethyan continental margin and experienced extensional faulting and differential subsidence during rifting of the future margin. The Mesozoic succession in the Julian Alps is characterized by a thick pile of Upper Triassic to Lower Jurassic platform limestones of the Julian Carbonate Platform, unconformably overlain by Bajocian to Tithonian strongly condensed limestones of the Prehodavci Formation of the Julian High. The Prehodavci Formation is up to 15 m thick, consists of Rosso Ammonitico type limestone and is subdivided into three members. The Lower Member consists of a condensed red, well-bedded bioclastic limestone with Fe–Mn nodules, passing into light-grey, faintly nodular limestone. The Middle Member occurs discontinuously and consists of thin-bedded micritic limestone. The Upper Member unconformably overlies the Lower or Middle Members. It is represented by red nodular limestone, and by red-marly limestone with abundant
Saccocoma
sp. The Prehodavci Formation unconformably overlies the Upper Triassic to Lower Jurassic platform limestone of the Julian Carbonate Platform; the contact is marked by a very irregular unconformity. It is overlain by the upper Tithonian pelagic Biancone (Maiolica) limestone. The sedimentary evolution of the Julian High is similar to that of Trento Plateau in the west and records: (1) emergence and karstification of part of the Julian Carbonate Platform in the Pliensbachian, or alternatively drowning of the platform and development of the surface by sea-floor dissolution; (2) accelerated subsidence and drowning in the Bajocian, and onset of the condensed pelagic sedimentation (Prehodavci Formation) on the Julian High; (3) beginning of sedimentation of the Biancone limestone in the late Tithonian.
Several geological and geochemical parameters were determined in the sediments of the 5th (5 J) and 6th (6 J) Triglav Lakes, Julian Alps (NW Slovenia), in order to study the impact of natural ...catchment characteristics and anthropogenic activity. Fish were introduced into both lakes in 1991 and a mountain hut lies on the shore of 5 J. Sedimentary grain size (GS) was distinctly coarser in 5 J than 6 J, with arithmetic means ranging between 46 and 60 and 23–36 μm, respectively. In contrast, the mineralogical composition of the two sediments was similar. Calcite predominated strongly, comprising more than 77 % of total minerals, while dolomite and quartz were rare. Organic carbon (OC) and total nitrogen (TN) concentrations were highest in surficial sediments, with levels of 14.4 and 1.8 %, and 19.3 and 2.4 % observed in 5 J and 6 J, respectively. C/N ratios (atomic) were lowest in the same surface sediments, with the two lakes characterized by similar values (9.6 vs. 9.4, respectively), suggesting a predominance of autochthonous organic matter (OM) in both lakes. Contemporary δ¹³C values were lower in 5 J (−21.0 ‰) than 6 J (−18.5 ‰) sediments. Considerable changes in these four parameters were observed in recently deposited material, reflecting a shift in the trophic status of both lakes that was likely induced by the introduction of fish. In addition, the smaller and shallower 6 J seemed to respond to changes faster than the larger and deeper 5 J, indicating the higher sensitivity of the former. δ¹⁵N values in surface sediments of 5 J and 6 J were −2.9 and −4.4 ‰, respectively, with levels increasing gradually with depth to approximately +1.0 ‰ in deeper sediments. The observed changes could most likely be attributed to the atmospheric deposition of reactive nitrogen. The mountain hut has seemingly not had a significant enough impact on the lakes to be recorded in their sediments.
This study deals with the macroscopic and microfacies characterisation of Roman stone artefacts excavated in 2006 from a Roman villa rustica near Mošnje (NW Slovenia) with the aim of defiing their ...provenance. A total of 28 representative fids (querns, mortars, whetstones, tooled and rounded stones, a fragment of stone slab, mosaic tesserae and two architectural elements - one with a relief) made of clastic and carbonate sedimentary rocks were examined. Comparison was made with rock samples taken from quarries and gravel bars close to the archaeological site, as well as from larger distance to the site. The majority of artefact sampled is composed of Upper Palaeozoic quartz sandstones, which are found as pebbles in gravel bars close to the archaeological site; while 2 samples were from Quaternary coarse grained clastic rocks which can be found in local glacio-flvial sediments. Other fids were made of four different Mesozoic shallow-water limestones which outcrop in different areas of Central and SW Slovenia. The nearest Lower Jurassic biopelmicritic limestones are found at the western periphery of Ljubljana in Podutik. Cretaceous miliolid limestones and biocalcarenitic limestones with rudists are common in the successions of the Dinaric Carbonate Platform in SW Slovenia (for example, on the Trieste-Komen Plateau), NE Italy and SW Croatia. This indicates that the limestones for architectural elements, stone mortars and tesserae were brought to Mošnje from distant locations. Smaller stone tools are likely to have been made at the location of the archaeological site from material gathered locally, mostly pebbles from clastic rocks, which were accessible and suitable for tooling.
Geotourism is a special form of tourism which focuses on visiting geological and geomorphological sites. In the article we discuss the basic terms regarding geotourism, geodiversity and ...geoconservation, and then present the main features of rock shelters, i.e. landforms whose formation has not yet been elucidated. In our opinion rock shelters in Slovenian Istria have a potential to become sites for geotourism. We evaluated the geotourism potential of five rock shelter locations: Veli Badin, Štrkljevica, Mi{ja pe~, Stena and Kav~i~. The results of the evaluation show that three of the chosen rock shelter locations have a potential to develop as geotourist sites. Research confirmed our assumptions that the lack of scientific knowledge about rock shelters is a weakness from the geotourist point of view. Beside more detailed research on rock shelters, other activities, e.g. management of the sites, creating tourist activities, information material etc. are also needed if we want rock shelters to become geotourist sites in the future.
The Perbla Formation represents typical Toarcian clay-rich pelagic sediment of the southern Tethyan passive continental margin. It was deposited in the Slovenian Basin, located in present-day western ...Slovenia. During the Early Jurassic the basin was surrounded by the Dinaric (Friuli) Carbonate Platform to the south and by the Julian Carbonate Platform to the north. Today, the transitional areas between the platforms and basin are not preserved due to intense Cainozoic thrusting and erosion, with the only record of the evolution of these areas stored in gravity-flow deposits of the Perbla Formation. Coarser turbidites were deposited on the margins of the basin, with other types of gravity-flow deposits, observed mainly in the central part of the basin. These intercalations reflect regionally recognized events that characterized the sedimentary evolution of western Slovenia at the end of the Early Jurassic. Slumps that occasionally developed into debris-flows reflect uneven sea-bottom palaeotopography that originated during a pre- to early-Toarcian phase of accelerated subsidence. The early Toarcian transgression caused drowning of the adjacent carbonate platforms, an event reflected in the composition of coarser turbidites which consist almost exclusively of echinoderm fragments and thin-shelled bivalves. These turbidites originated from drowned platform margins and/or slopes and were subsequently redeposited in proximal parts of the basin.
We present a study on the impact of litho-structural setting and neotectonic activity on meso- and macro-scale relief production in Alpine areas. The topography of the high alpine Triglav Lakes ...Valley, NW Slovenia, was studied by means of detailed mapping and stratigraphic study of the valley. The Triglav Lakes Valley is characterised by a generally asymmetric transverse (E–W) profile: a very steep eastern slope, a relatively flat valley and a relatively gentle western slope. On the transverse profile the valley floor is essentially flat, gently dipping towards the east. In the longitudinal cross-section, however, the valley floor is marked by sharply-defined fault blocks extending in a W–E to NW–SE direction. Additionally, the highest block (elevations ∼
2100 m) is in the northern part of the valley, the lowest (elevations ∼
1600 m) in the southern part of the valley. Our research shows that the Triglav Lakes Valley directly represents the topographic expression of Paleogene–Neogene thrusting and faulting, having recorded the following geomorphologic evolutionary stages: 1. an Oligocene to early Miocene W-vergent thrusting phase, with steep W-facing slopes of the eastern part of the valley directly representing the thrusting front; and 2. a Neogene-to-present strike–slip faulting in NNE–SSW direction with two bifurcating right-lateral strike–slip systems. We show that the Triglav Lakes Valley almost perfectly mimics the wedge-shaped damage zone located between these faults.
Successions of the Slovenian Basin structurally belong to the easternmost Southern Alps. During the Late Triassic, they were part of the Adriatic continental margin. Norian–Rhaetian successions of ...the Slovenian Basin are characterized mainly by dolomite of the Bača Dolomite Formation. However, in the northern part of the basin, Late Triassic limestone is preserved above Bača Dolomite Formation and is formalized as the Slatnik Formation. It is composed of hemipelagic limestone alternating with resedimented limestones. The succession documents an upward progradation of the slope environment composed of three high-frequency cycles. Most prominent progradation is referred to the second, i.e., Early Rhaetian cycle. The Slatnik Formation ends with thin-bedded hemipelagic limestone that records the end-Triassic productivity crisis, or rapid sea-level fall. The overlying resedimented limestones of the Early Jurassic Krikov Formation, document the recovery of production and shedding from the adjacent carbonate platform.
Twelve species of genera Diplotremina Kristan-Tollmann, 1960, Duostomina Kristan-Tollmann, 1960, and Variostoma Kristan-Tollmann, 1960 have been described from the Norian and Rhaetian strata of the ...Slovenian Basin (eastern Southern Alps). A lamellar wall structure has been confirmed for Duostomina and observed for the first time in Variostoma. The multi-layered nature of the lamellae of Diplotremina and Duostomina may be a result of a diagenetic alteration of the single-layered lamellae. The position of Variostoma in the family Duostominidae remains doubtful due to the alveolar nature of its wall.
A complete Jurassic succession, recording the evolution from platform margin to a deep-water basin, is exposed at Mt. Mangart in the Julian Alps. The succession is a part of the Julian Nappe, where ...the Southern Alps overlap with the Dinarides. In the Jurassic, the area comprised part of the south Tethyan passive continental margin. The section was studied sedimentologically in detail and dated with radiolarians. It is divided into five lithostratigraphic units: Unit 1: Lower Jurassic shallow-water peloidal and oncoidal limestones; Unit 2: Pliensbachian distal shelf limestones rich in juvenile ammonites and sponge spicules topped by an Fe-Mn hardground; Unit 3: lower to possibly middle Toarcian sequence of black shales with interbedded siliceous limestone; Unit 4: upper Bajocian/Bathonian to lower Tithonian cherts, cherty limestones, and carbonate gravity-flow deposits; Unit 5: upper Tithonian red nodular cherty limestones with abundant calpionellids and aptychi. A stratigraphic gap, comprising the late Toarcian to early Bajocian, separates Unit 4 from Unit 3. In general, the succession correlates well with known Tethyan transgressive/regressive facies cycles. In addition, two periods of accelerated subsidence were recognized, the first, in the Pliensbachian, drowned the platform, the second, prior to the late Bajocian, created accommodation space for resedimented carbonate deposits from the adjacent Friuli Carbonate Platform. The present day position of the succession is between the Belluno Basin to the west and the Slovenian Basin to the south. The hitherto described successions of these two basins were located more distally from the Friuli Carbonate Platform than the Mt. Mangart succession.
Jurassic neptunian dikes are common within Upper Triassic to Lower Jurassic platform limestone of the Julian Alps. At Mt Mangart, the following geometries were observed: irregular dissolution ...cavities, thin penetrative fractures, larger fractures with sharp sidewalls, and laterally confined breccia bodies. Inside a complex neptunian dike system two main generations of infillings were differentiated. The first generation is heterogeneous and consists of bioclastic limestones, representing uniquely preserved sediments subdivided into five different microfacies. The second generation is more common and typically consists of coarse-grained breccias with host-rock clasts and marly limestone matrix containing echinoderms. Fracture formation and void filling of the first generation of neptunian dikes is dated as Pliensbachian and is interpreted to be caused by the Julian carbonate platform dissection due to widely recognized Lower Jurassic Tethyan rifting. The timing of formation for the second generation is only broadly constrained, ranging from the Pliensbachian to the Late Cretaceous.PUBLICATION ABSTRACT
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