The Jurassic Prehodavci Formation of the Julian Alps: easternmost outcrops of Rosso Ammonitico in the Southern Alps (NW Slovenia)

Abstract We conducted a phytosociological study of the communities hosting the rare and endangered fern Adiantum capillus-veneris in the foothills of the Julian Alps, in Karst and in Istria. Based on a comparison with similar communities elsewhere in the southern Alps (northern Italy) we classified most of the recorded stands into the syntaxa Eucladio-Adiantetum eucladietosum and -cratoneuretosum commutati. Releves from the southern Julian Alps, located in comparatively slightly colder and moister local climate and the dolomite bedrock are classified into the new subassociation -hymenostylietosum recurvirostri subass. nova. Stands with the abundant occurrence of the liverwort Conocephalum conicum, are classified in to the new subassociation -conocephaletosum conici subass. nova. Stands in conglomerate rock shelters along the Soča at Solkan are classified into the new association Phyteumato columnae-Adiantetum ass. nova, a community of transitional character between the classes Adiantetea capilli-veneris and Asplenietea trichomanis.

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Micro-displacement monitoring in caves at the Southern Alps–Dinarides–Southwestern Pannonian Basin junction

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-021-02382-4 ◽

2021 ◽

Author(s):

Stanka Šebela ◽

Josef Stemberk ◽

Miloš Briestenský

Keyword(s):

Pannonian Basin ◽

Bedding Plane ◽

Vertical Movement ◽

Southern Alps ◽

Tectonic Activity ◽

First Episode ◽

Displacement Monitoring ◽

Active Tectonic ◽

Julian Alps ◽

Continuous Displacement

AbstractIn situ micro-displacement monitoring in caves at the seismically active junction of the Southern Alps, Dinarides and Southwestern Pannonian Basin revealed active tectonic micro-deformations. The largest total vertical movement of 0.35 mm (2008–2018) occurred at Kostanjeviška Jama (Southwestern Pannonian Basin–Dinarides). Two abrupt displacements observed at that cave location correspond to pre- and post-seismic episodes in 2014 and 2015. At Pološka Jama (Southern Alps), more gradual and continuous displacement on a monitored bedding plane of 0.13 mm down-slip (2008–2018) was observed. This movement is attributed to slope relaxation as well as tectonic activity on the Julian Alps thrust fault and the seismogenic Ravne Fault, which generated earthquakes at Mw = 5.6 in 1998 and Mw = 5.2 in 2004. At Jama pri Svetih Treh Kraljih in Dinarides, activity on the Ravne Fault was shown as sinistral-horizontal (0.1 mm) and vertical (0.15 mm) movement along an E–W-oriented tectonic structure. This shallowly buried site also experienced cyclic seasonal displacements. At Županova Jama, multiple short-term horizontal dextral and sinistral strike-slip pulses (2016–2018) demonstrated active tectonic micro-deformations within the wider zone of the Dobrepolje and Želimlje faults. At Postojnska Jama, two episodes of vertical movement on a NW–SE-oriented fault are associated with earthquake swarms: the first episode was in 2010 (MLV = 3.7) and the second in 2014 (MLV = 4.3). In-cave flood events do not coincide with periods of micro-displacement activity in the studied caves, and therefore are not the drivers of the micro-displacement.

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Snow-bed communities with dominant Salix herbacea in the Julian Alps

Hacquetia ◽

10.2478/hacq-2018-0007 ◽

2019 ◽

Vol 18 (1) ◽

pp. 47-73

Author(s):

Andrej Martinčič ◽

Tone Wraber ◽

Igor Dakskobler

Keyword(s):

Southern Alps ◽

Flowering Plants ◽

Moss Species ◽

Rock Wall ◽

Alpine Belt ◽

New Association ◽

Julian Alps ◽

Salix Herbacea ◽

Successional Stages ◽

Salicion Herbaceae

Abstract In the alpine belt of the Julian Alps (glacial cirque Na Jezerih under Mt. Veliki Rokav, Jarečica, the Mangart Saddle and Prodi under Mt. Mangart as well as Mt. Plešivec in the rock wall of Loška Stena) we studied the phytosociology and ecology of snow-bed vegetation with dominating flowering plants Salix herbacea, Luzula alpinopilosa, Gnaphalium supinum, Soldanella pusilla and Salix retusa, and numerous moss species. Based on the comparison with similar snow-bed communities in the Central, Eastern and Southern Alps we described a new association Salicetum retuso-herbaceae and classified it into the alliance Salicion herbaceae and class Salicetea herbaceae. We determined several successional stages of snow-bed vegetation on mixed calcareous-silicate bedrock that we treat as variants, in two relevés also the initial association Polytrichetum sexangularis.

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Paleogeographic significance of Upper Triassic basinal succession of the Tamar Valley, northern Julian Alps (Slovenia)

Geologica Carpathica ◽

10.1515/geoca-2015-0025 ◽

2015 ◽

Vol 66 (4) ◽

pp. 269-283 ◽

Cited By ~ 11

Author(s):

Luka Gale ◽

Bogomir Celarc ◽

Marcello Caggiati ◽

Tea Kolar-Jurkovšek ◽

Bogdan Jurkovšek ◽

...

Keyword(s):

Shallow Water ◽

Southern Alps ◽

Upper Triassic ◽

Santo Stefano ◽

Dolomia Principale ◽

Julian Alps ◽

Shallow Subtidal ◽

Platform Carbonates ◽

Slovenian Basin ◽

Marly Limestone

AbstractThe Julian Alps (western Slovenia) structurally belong to the eastern Southern Alps. The Upper Triassic succession mostly consists of shallow water platform carbonates of the Dolomia Principale-Dachstein Limestone system and a deep water succession of the Slovenian Basin outcropping in the southern foothills of the Julian Alps. In addition to the Slovenian Basin, a few other intraplatform basins were present, but they remain poorly researched and virtually ignored in the existing paleogeographic reconstructions of the eastern Southern Alps. Herein, we describe a deepening-upward succession from the Tamar Valley (north-western Slovenia), belonging to the Upper Triassic Tarvisio Basin. The lower, Julian-Tuvalian part of the section comprises peritidal to shallow subtidal carbonates (Conzen Dolomite and Portella Dolomite), and an intermediate carbonate-siliciclastic unit, reflecting increased terrigenous input and storm-influenced deposition (Julian-lowermost Tuvalian shallow-water marlstone and marly limestone of the Tor Formation). Above the drowning unconformity at the top of the Portella Dolomite, Tuvalian well-bedded dolomite with claystone intercalations follows (Carnitza Formation). The latter gradually passes into the uppermost Tuvalian–lowermost Rhaetian bedded dolomite with chert and slump breccias, deposited on a slope and/or at the toe-of-slope (Bača Dolomite). Finally, basinal thin-bedded bituminous limestone and marlstone of Rhaetian age follow (Frauenkogel Formation). The upper part of the Frauenkogel Formation contains meter-scale platform-derived limestone blocks, which are signs of platform progradation. The Tarvisio Basin may have extended as far as the present Santo Stefano di Cadore area, representing a notable paleogeographic unit at the western Neotethys margin.

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