Mineraloške in kemijske značilnosti črnih prevlek v Postojnskem jamskem sistemu Črne prevleke iz ... more Mineraloške in kemijske značilnosti črnih prevlek v Postojnskem jamskem sistemu Črne prevleke iz dveh nahajališč v Postojnskem jamskem siste mu so bile mineraloško in kemijsko analizirane. Naključni vzorci so bili pobrani iz vhodnih delov jame in iz Črne jame. Vzorce smo analizirali v polarizirani presevni svetlobi, z rentgen sko difrakcijsko metodo ter z vrstičnim elektronskim mikroskopom z energijsko disperzijskim spektrometrom rentgen skih žarkov (SEM/EDS). Mikroskopska preiskava zbruskov iz obeh lokacij je pokazala, da je glavna sestavina črnih prevlek karbonat-kalcit, s posameznimi večinoma zelo majhnimi neprozornimi črnimi zrni. Metoda rentgenske difrakcije iz obeh nahajališč je potrdila le prisotnost kalcita in v manjši meri kremena in dolomita, pri čemer je izločila prisotnost Mn in Fe oksidov ali apatitove skupine mineralov (gvano netopirjev) kot vzrok za črne prevleke. SEM/EDS analiza vzorcev iz vhodnih delov Postojnskega jamskega sistema je potrdila analizo rentgenske difrakcije, ki ni pokazala Mn oksidov. Visoka vsebnost C, merjenega v črnih prevlekah iz vhodnih delov jame, potrjuje organski C, ki se je odložil na jamske stene v obdobju eksplozije bencina med 2.svetovno vojno. Tudi črne prevleke iz Črne jame lahko pripišemo organskemu C, ki pa je zagotovo drugačen od tistega v vhodnih delih Postojnskega jamskega sistema. Ker iz Črne jame ni znanih dokazov o starih poselitvah, so bakle prvih turistov najverjetnejši vzrok za oglje. Na obeh lokacijah bi morda lahko črne prevleke vsaj deloma razlagali z mikroklimatskimi razmerami na vhodih v jamo, ki so povzročili odlaganje organskega materiala zunanjega izvora (npr. saje gozdnih požarov).
The project RI-SI-EPOS (Research Infrastructure-Slovenia-European Plate Observing System) provide... more The project RI-SI-EPOS (Research Infrastructure-Slovenia-European Plate Observing System) provided new scientific equipment for solid Earth science related to geology, seismology, geodesy and karstology. Karst research infrastructure is primarily used at the SLO KARST NFO (Near Fault Observatory) developing site. The area covers ~ 2600 km 2 and is one of the most seismically active areas in SW Slovenia. It consists mostly of karstified Mesozoic carbonate rocks and partly of non-karstified Eocene flysch. The landscape has numerous karst features including caves, poljes, dolines, uvalas, karst springs, ponors and periodic karst lakes, with typical karst underground water drainage. Site development commenced with the installation of seven temporary seismic stations in the area, along with other geoscience equipment (gravimeter, 3D laser terrestrial scanner, GNSS antenna, TM72 extensometers, spectrometer for methane and drone), deployed in 2020. With the new dense seismic network, locations and other seismic parameters are already determined more reliably than in the past, contributing to a better understanding of active tectonic deformations at the junction between the seismically active Friuli region (Italy) and the Zagreb-Petrinja area (Croatia). The new solid Earth Geoscience research infrastructure is already collecting a big amount of data following the FAIR principles (making data Findable, Accessible, Interoperable and Reusable) aiming to be included in the national and international research databases. Here, the first results from the newly operating SLO KARST NFO temporary seismic network (May 2020-June 2021) are discussed.
Historical air temperatures at three karst caves in Slovenia have been compared to current data t... more Historical air temperatures at three karst caves in Slovenia have been compared to current data time series. In Postojnska Jama (PJ), the most visited show cave in Slovenia, the significant temperature difference between historical and modern measurements at the Pulpito site relates to the months April to November. Mean monthly temperatures measured at the Sepolcro site (PJ) in the modern period (2016-2019) are year round significantly higher than in the historical period (1935-1937). The temperature increase over the last 85 years in PJ is attributed to outside temperature rise and additional heat input from visitors, especially for Sepolcro site. A comparison of current (2017-2019) and historical (1956-1957) temperature data in touristically poorly visited Predjama Cave shows lower increase as in PJ and is completely related to outside cave conditions. In the case of Škocjanske Jame (Tiha Jama), air temperature has not significantly increased since the historical 1928 measurements because the monitoring site looks to be morphologically isolated from significant impacts of outside climate and visitors.
This chapter introduces Skocjanske jame (Skocjan Caves) and their immediate karstic surroundings ... more This chapter introduces Skocjanske jame (Skocjan Caves) and their immediate karstic surroundings to those who are not already familiar with the place, and its overall history over several centuries.
We present methodologies for the multi-parameter observations of pre-earthquake phenomena and the... more We present methodologies for the multi-parameter observations of pre-earthquake phenomena and their retrospective/ prospective testing. The hypothesis that the strongest earthquakes depend on the global stress field leads to global observations and a multi-parameter and multi-sensors approach. In 2012 we performed coordinated tests of several geophysical and environmental parameters, which are associated with the earthquakes preparation processes, namely: 1) Rocks deformation measurements (Kalenda et al. 2012); 2) Subterranean non-stationary electric processes (Bobrovskij 2011); 3) superconducting gravimeters (SGs) records and broadband seismometers (BS) time series (Shen et al); and 4) satellite infra-red observations (10-13 �m) measured at the top of the atmosphere (Ouzounov et al , 2011). In the retrospective test for the two most recent major events in Asia: Wenchuan earthquake (2008,China) and the latest Tohoku earthquake/tsunami (2011, Japan) our combined analysis showed a coo...
The surface above the longest Slovene karst cave Postojnska Jama Cave System (20 km) is character... more The surface above the longest Slovene karst cave Postojnska Jama Cave System (20 km) is characterized by numerous dolines and collapse dolines. We have 17 collapse dolines in the area of 2,55 km 2. They vary in depth, shape and size. Some have steep slopes where collapse blocks look fresh others are relics of former collapse dolines with gentle slopes. The deepest collapse doline is basically the entrance shaft to Pivka Jama Cave (77 m), the biggest collapse doline is Vodni dol (600x240x60 m). Most of collapse dolines is situated near the crest of Postojna anticline, on it's northern flank. Development and especially deepening of collapse dolines like Velika and Mala Jeršanova doline, Vodni dol and Kozja Jama has a genetic connection with the lowering of Postojnska Jama Cave System active water passage into SW and NW passages due to the regional tectonic uplifting.
UDC 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Surface vers... more UDC 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Surface versus underground measurements of active tectonic displacements with TM 71 exstensometers in Slovenia The tectonic setting of W Slovenia is characterised by NW-SE trending dextral strike-slip fault systems and moderate seismicity. Monitoring of tectonic movements along five presumably active faults or in their vicinity using TM 71 extensometers was set up in 2004. In five years of monitoring some clear trends of displacement were established. The morphologically most prominent fault in W Slovenia is Idrija Fault having a total length of more than 120 km. The average lateral displacement measured along a crack in its inner fault zone in Učja valley was 0.26 mm/year. Short-term rates were even greater and reached 0.54 mm/year. Raša Fault monitoring site at the foot of Vremščica Mt. established first an average uplift of SW block for 0.16 mm/year and left-lateral displacement of 0.16 mm/ year. It was followed by down-slip of the same block at the rate of 0.37 mm/year. In Postojnska Jama two instruments, 260 m apart, were installed at the fault zone, which extends about 1 km northeast from Predjama Fault. We detect small tectonic deformations, dextral horizontal movement of 0.05 mm in 5 years for Postojna 1 and extension of 0.03 mm in 5 years for Postojna 2. Both devices recorded similar reactions to some earthquakes with magnitude range 3.1-5.2 and epicentral distance of 12-95 km. The amplitude of individual peaks is in the order of 0.08 mm. The monitoring at Kneža Fault started at the end of 2006. In two years clear oblique displacement was established with left-lateral rate of 0.06 mm/year and uplift of SW block for 0.06 mm/year. Monitoring in Pološka Jama situated in vicinity of the Ravne Fault started in 2008. Preliminary results show 0.08 mm of horizontal displacement between two Izvleček UDK 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Primerjava površinskih in podzemeljskih meritev aktivnih tektonskih premikov določenih s TM 71 ekstenziometri v zahodni Sloveniji Za tektonsko zgradbo zahodne Slovenije so značilni sistemi desnozmičnih prelomov usmerjeni NW-SE in zmerna potresna dejavnost. Leta 2004 smo pričeli z meritvami tektonskih premikov z ekstenziometri TM 71 ob petih domnevno aktivnih prelomih ali v njihovi bližini. V petih letih opazovanj smo ugotovili nekatere jasne trende premikov. Morfološko najmočneje izražen prelom v zahodni Sloveniji je Idrijski prelom, ki je dolg preko 120 km. Na razpoki v njegovi notranji coni v dolini Učje smo ugotovili povprečne zmične premike 0,26 mm/leto. Kratkotrajnejše hitrosti so še večje in dosežejo 0,54 mm/leto. Na Raškem prelomu v vznožju Vremščice smo ugotovili najprej dvigovanje SW bloka za 0,16 mm/leto in levozmične premike s hitrostjo 0,16 mm/leto. Sledilo je pogrezanje istega bloka za 0,37 mm/leto. V Postojnskem jamskem sistemu smo na razdalji 260 m namestili dva inštrumenta na prelomni coni, ki poteka okoli 1 km severovzhodno od Predjamskega preloma. Beležimo majhne tektonske premike, desni zmik za 0,05 mm v petih letih za Postojno 1 in ekstenzijo velikosti 0,03 mm v petih letih za Postojno 2. Oba ekstenziometra sta se podobno odzvala na nekatere potrese z magnitudami v območju 3.1-5.2 in epicentralno oddaljenostjo 12-95 km. Amplituda posameznih vrhov je reda velikosti 0,08 mm. Opazovanje na Knežkem prelomu se je pričelo konec 2006. V dveh letih smo izmerili poševno zmikanje z desnozmično hitrostjo 0,06 mm/leto in dvigovanje SW bloka za 0,06 mm/leto. Opazovanje v Pološki jami, ki se nahaja v bližini Ravenskega preloma se je začelo v letu 2008. Preliminarni rezultati kažejo horizontalni premik 0,08 mm med brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by ZRC SAZU Publishing (Znanstvenoraziskovalni center-Slovenske akademije znanosti... ACTA CARSOLOGICA 38/2-3-2009 214 limestone beds. Established displacements proved the active tectonic movement of all monitored faults. Observed deformation rates can be compared with the regional deformation rate in W Slovenia established from GPS measurement, which is in the order of 2 mm/year.
The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transi... more The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transient deformations across individual faults. This paper presents the first results from two newly established monitoring points in the Balkan Mountains in Bulgaria. The data from Saeva Dupka, recorded across an EEN-WWS striking fault, show sinistral strike-slip along the fault and subsidence of the southern block. Much of the subsidence occurred around the time of the distal M W = 5.6 Pernik Earthquake. An important transient deformation event, which began in autumn 2012, was reflected by significant compression and following extension, across the monitored fault. The data from Bacho Kiro, recorded across a NE-SW striking fault, show sinistral strike-slip along the fault and subsidence of the northwestern block. The same important deformation event was reflected by changes in the strike-slip, dip-slip, and horizontal opening/closing trends. These results have been compared to data from other monitoring points in the Western Carpathians, External Dinarides, and Tian Shan. Many of the sites show evidence of simultaneous displacement anomalies and this observation is interpreted as a reflection of the plate-wide propagation of a tectonic pressure pulse towards the end of 2012.
We report the results of 3-years of Radon-222 monitoring in six show caves across Europe, selecte... more We report the results of 3-years of Radon-222 monitoring in six show caves across Europe, selected with the feature of having only one, or no natural entrance, defined as dead-end caves. The caves are located in Spain, Slovakia, Slovenia, and Czechia. The consecutive monitoring was performed between January 2017 and January 2020. Continuous measurements of the radon activity concentration using spectrometry detection and analysis of the α-particles of 222Rn progeny were performed. Meteorological parameters influencing gas flow were recorded inside and outside of the caves. Although the radon activity concentrations differed from one cave to another, all six of the studied caves revealed very similar trends, showing evident seasonal variability with higher values in summer and lower values in winter. The measured values of radon activity concentrations ranged between 633 and 26,785 Bq/m3. The temperature differences between the inside and outside of the caves is the main radon moveme...
Izvle~ek UDK: 551.44(77) Stanka [ebela & Randall C. Orndorff & David J. Weary: Geolo{ke zakonitos... more Izvle~ek UDK: 551.44(77) Stanka [ebela & Randall C. Orndorff & David J. Weary: Geolo{ke zakonitosti pri razvoju jam v osrednjem delu ju'nih Ozarkov, Missouri, ZDA Podro~je Ozarkov v Missouriju je eden najve~jih kra{kih terenov v ZDA. Prevladujo~o litologijo predstavljajo kambrijski in ordovicijski dolomiti in pe{~enjaki. [tevilne, ve~inoma horizontalne jame in veliki kra{ki izviri so zna~ilnosti krasa Ozarkov. Od oktobra 1996 do vklju~no maja 1999 smo obiskali 23 kra{kih jam, za 18 jam v osrednjem delu ju'nih Ozarkov smo naredili geolo{ke karte. Za ta ~lanek smo predstavili geologijo {tirih jam. Prevladujo~a geolo{ka zakonitost, ki vpliva na oblikovanje jam je vpad plasti in preferen~na plast stromatolitnega dolomita. Edina mo'na povezava med geolo{ko strukturo in smerjo jamskih rovov je smer rovov sever-jug in smer razpok sever-jug.
Na primeru treh odsekov rovov v Postojnski jami je bila proucevana njihova speleogeneza. Pokazalo... more Na primeru treh odsekov rovov v Postojnski jami je bila proucevana njihova speleogeneza. Pokazalo se je, da so oblikovane po lezikah, zdrsnih lezikah in veznih razpokah.Ugodnost le nekaterih lezik in zdrsnih lezik za speleogenezo je v njihovi povezanosti v penetrativno efektivno poroznost v dolocenem strukturnem bloku. In 3 examples of passage parts from Postojnska Jama their speleogenesis was studied. It was shown that they are formed along bedding planes, moved bedding planes and connective fissures. The advantage for speleogenesis of some bedding planes and moved bedding planes is represented with their connection into penetrative effective porosity in specific structural block.
Mineraloške in kemijske značilnosti črnih prevlek v Postojnskem jamskem sistemu Črne prevleke iz ... more Mineraloške in kemijske značilnosti črnih prevlek v Postojnskem jamskem sistemu Črne prevleke iz dveh nahajališč v Postojnskem jamskem siste mu so bile mineraloško in kemijsko analizirane. Naključni vzorci so bili pobrani iz vhodnih delov jame in iz Črne jame. Vzorce smo analizirali v polarizirani presevni svetlobi, z rentgen sko difrakcijsko metodo ter z vrstičnim elektronskim mikroskopom z energijsko disperzijskim spektrometrom rentgen skih žarkov (SEM/EDS). Mikroskopska preiskava zbruskov iz obeh lokacij je pokazala, da je glavna sestavina črnih prevlek karbonat-kalcit, s posameznimi večinoma zelo majhnimi neprozornimi črnimi zrni. Metoda rentgenske difrakcije iz obeh nahajališč je potrdila le prisotnost kalcita in v manjši meri kremena in dolomita, pri čemer je izločila prisotnost Mn in Fe oksidov ali apatitove skupine mineralov (gvano netopirjev) kot vzrok za črne prevleke. SEM/EDS analiza vzorcev iz vhodnih delov Postojnskega jamskega sistema je potrdila analizo rentgenske difrakcije, ki ni pokazala Mn oksidov. Visoka vsebnost C, merjenega v črnih prevlekah iz vhodnih delov jame, potrjuje organski C, ki se je odložil na jamske stene v obdobju eksplozije bencina med 2.svetovno vojno. Tudi črne prevleke iz Črne jame lahko pripišemo organskemu C, ki pa je zagotovo drugačen od tistega v vhodnih delih Postojnskega jamskega sistema. Ker iz Črne jame ni znanih dokazov o starih poselitvah, so bakle prvih turistov najverjetnejši vzrok za oglje. Na obeh lokacijah bi morda lahko črne prevleke vsaj deloma razlagali z mikroklimatskimi razmerami na vhodih v jamo, ki so povzročili odlaganje organskega materiala zunanjega izvora (npr. saje gozdnih požarov).
The project RI-SI-EPOS (Research Infrastructure-Slovenia-European Plate Observing System) provide... more The project RI-SI-EPOS (Research Infrastructure-Slovenia-European Plate Observing System) provided new scientific equipment for solid Earth science related to geology, seismology, geodesy and karstology. Karst research infrastructure is primarily used at the SLO KARST NFO (Near Fault Observatory) developing site. The area covers ~ 2600 km 2 and is one of the most seismically active areas in SW Slovenia. It consists mostly of karstified Mesozoic carbonate rocks and partly of non-karstified Eocene flysch. The landscape has numerous karst features including caves, poljes, dolines, uvalas, karst springs, ponors and periodic karst lakes, with typical karst underground water drainage. Site development commenced with the installation of seven temporary seismic stations in the area, along with other geoscience equipment (gravimeter, 3D laser terrestrial scanner, GNSS antenna, TM72 extensometers, spectrometer for methane and drone), deployed in 2020. With the new dense seismic network, locations and other seismic parameters are already determined more reliably than in the past, contributing to a better understanding of active tectonic deformations at the junction between the seismically active Friuli region (Italy) and the Zagreb-Petrinja area (Croatia). The new solid Earth Geoscience research infrastructure is already collecting a big amount of data following the FAIR principles (making data Findable, Accessible, Interoperable and Reusable) aiming to be included in the national and international research databases. Here, the first results from the newly operating SLO KARST NFO temporary seismic network (May 2020-June 2021) are discussed.
Historical air temperatures at three karst caves in Slovenia have been compared to current data t... more Historical air temperatures at three karst caves in Slovenia have been compared to current data time series. In Postojnska Jama (PJ), the most visited show cave in Slovenia, the significant temperature difference between historical and modern measurements at the Pulpito site relates to the months April to November. Mean monthly temperatures measured at the Sepolcro site (PJ) in the modern period (2016-2019) are year round significantly higher than in the historical period (1935-1937). The temperature increase over the last 85 years in PJ is attributed to outside temperature rise and additional heat input from visitors, especially for Sepolcro site. A comparison of current (2017-2019) and historical (1956-1957) temperature data in touristically poorly visited Predjama Cave shows lower increase as in PJ and is completely related to outside cave conditions. In the case of Škocjanske Jame (Tiha Jama), air temperature has not significantly increased since the historical 1928 measurements because the monitoring site looks to be morphologically isolated from significant impacts of outside climate and visitors.
This chapter introduces Skocjanske jame (Skocjan Caves) and their immediate karstic surroundings ... more This chapter introduces Skocjanske jame (Skocjan Caves) and their immediate karstic surroundings to those who are not already familiar with the place, and its overall history over several centuries.
We present methodologies for the multi-parameter observations of pre-earthquake phenomena and the... more We present methodologies for the multi-parameter observations of pre-earthquake phenomena and their retrospective/ prospective testing. The hypothesis that the strongest earthquakes depend on the global stress field leads to global observations and a multi-parameter and multi-sensors approach. In 2012 we performed coordinated tests of several geophysical and environmental parameters, which are associated with the earthquakes preparation processes, namely: 1) Rocks deformation measurements (Kalenda et al. 2012); 2) Subterranean non-stationary electric processes (Bobrovskij 2011); 3) superconducting gravimeters (SGs) records and broadband seismometers (BS) time series (Shen et al); and 4) satellite infra-red observations (10-13 �m) measured at the top of the atmosphere (Ouzounov et al , 2011). In the retrospective test for the two most recent major events in Asia: Wenchuan earthquake (2008,China) and the latest Tohoku earthquake/tsunami (2011, Japan) our combined analysis showed a coo...
The surface above the longest Slovene karst cave Postojnska Jama Cave System (20 km) is character... more The surface above the longest Slovene karst cave Postojnska Jama Cave System (20 km) is characterized by numerous dolines and collapse dolines. We have 17 collapse dolines in the area of 2,55 km 2. They vary in depth, shape and size. Some have steep slopes where collapse blocks look fresh others are relics of former collapse dolines with gentle slopes. The deepest collapse doline is basically the entrance shaft to Pivka Jama Cave (77 m), the biggest collapse doline is Vodni dol (600x240x60 m). Most of collapse dolines is situated near the crest of Postojna anticline, on it's northern flank. Development and especially deepening of collapse dolines like Velika and Mala Jeršanova doline, Vodni dol and Kozja Jama has a genetic connection with the lowering of Postojnska Jama Cave System active water passage into SW and NW passages due to the regional tectonic uplifting.
UDC 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Surface vers... more UDC 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Surface versus underground measurements of active tectonic displacements with TM 71 exstensometers in Slovenia The tectonic setting of W Slovenia is characterised by NW-SE trending dextral strike-slip fault systems and moderate seismicity. Monitoring of tectonic movements along five presumably active faults or in their vicinity using TM 71 extensometers was set up in 2004. In five years of monitoring some clear trends of displacement were established. The morphologically most prominent fault in W Slovenia is Idrija Fault having a total length of more than 120 km. The average lateral displacement measured along a crack in its inner fault zone in Učja valley was 0.26 mm/year. Short-term rates were even greater and reached 0.54 mm/year. Raša Fault monitoring site at the foot of Vremščica Mt. established first an average uplift of SW block for 0.16 mm/year and left-lateral displacement of 0.16 mm/ year. It was followed by down-slip of the same block at the rate of 0.37 mm/year. In Postojnska Jama two instruments, 260 m apart, were installed at the fault zone, which extends about 1 km northeast from Predjama Fault. We detect small tectonic deformations, dextral horizontal movement of 0.05 mm in 5 years for Postojna 1 and extension of 0.03 mm in 5 years for Postojna 2. Both devices recorded similar reactions to some earthquakes with magnitude range 3.1-5.2 and epicentral distance of 12-95 km. The amplitude of individual peaks is in the order of 0.08 mm. The monitoring at Kneža Fault started at the end of 2006. In two years clear oblique displacement was established with left-lateral rate of 0.06 mm/year and uplift of SW block for 0.06 mm/year. Monitoring in Pološka Jama situated in vicinity of the Ravne Fault started in 2008. Preliminary results show 0.08 mm of horizontal displacement between two Izvleček UDK 551.24(497.4-15) Andrej Gosar, Stanka Šebela, Blahoslav Košťák & Josef Stemberk: Primerjava površinskih in podzemeljskih meritev aktivnih tektonskih premikov določenih s TM 71 ekstenziometri v zahodni Sloveniji Za tektonsko zgradbo zahodne Slovenije so značilni sistemi desnozmičnih prelomov usmerjeni NW-SE in zmerna potresna dejavnost. Leta 2004 smo pričeli z meritvami tektonskih premikov z ekstenziometri TM 71 ob petih domnevno aktivnih prelomih ali v njihovi bližini. V petih letih opazovanj smo ugotovili nekatere jasne trende premikov. Morfološko najmočneje izražen prelom v zahodni Sloveniji je Idrijski prelom, ki je dolg preko 120 km. Na razpoki v njegovi notranji coni v dolini Učje smo ugotovili povprečne zmične premike 0,26 mm/leto. Kratkotrajnejše hitrosti so še večje in dosežejo 0,54 mm/leto. Na Raškem prelomu v vznožju Vremščice smo ugotovili najprej dvigovanje SW bloka za 0,16 mm/leto in levozmične premike s hitrostjo 0,16 mm/leto. Sledilo je pogrezanje istega bloka za 0,37 mm/leto. V Postojnskem jamskem sistemu smo na razdalji 260 m namestili dva inštrumenta na prelomni coni, ki poteka okoli 1 km severovzhodno od Predjamskega preloma. Beležimo majhne tektonske premike, desni zmik za 0,05 mm v petih letih za Postojno 1 in ekstenzijo velikosti 0,03 mm v petih letih za Postojno 2. Oba ekstenziometra sta se podobno odzvala na nekatere potrese z magnitudami v območju 3.1-5.2 in epicentralno oddaljenostjo 12-95 km. Amplituda posameznih vrhov je reda velikosti 0,08 mm. Opazovanje na Knežkem prelomu se je pričelo konec 2006. V dveh letih smo izmerili poševno zmikanje z desnozmično hitrostjo 0,06 mm/leto in dvigovanje SW bloka za 0,06 mm/leto. Opazovanje v Pološki jami, ki se nahaja v bližini Ravenskega preloma se je začelo v letu 2008. Preliminarni rezultati kažejo horizontalni premik 0,08 mm med brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by ZRC SAZU Publishing (Znanstvenoraziskovalni center-Slovenske akademije znanosti... ACTA CARSOLOGICA 38/2-3-2009 214 limestone beds. Established displacements proved the active tectonic movement of all monitored faults. Observed deformation rates can be compared with the regional deformation rate in W Slovenia established from GPS measurement, which is in the order of 2 mm/year.
The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transi... more The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transient deformations across individual faults. This paper presents the first results from two newly established monitoring points in the Balkan Mountains in Bulgaria. The data from Saeva Dupka, recorded across an EEN-WWS striking fault, show sinistral strike-slip along the fault and subsidence of the southern block. Much of the subsidence occurred around the time of the distal M W = 5.6 Pernik Earthquake. An important transient deformation event, which began in autumn 2012, was reflected by significant compression and following extension, across the monitored fault. The data from Bacho Kiro, recorded across a NE-SW striking fault, show sinistral strike-slip along the fault and subsidence of the northwestern block. The same important deformation event was reflected by changes in the strike-slip, dip-slip, and horizontal opening/closing trends. These results have been compared to data from other monitoring points in the Western Carpathians, External Dinarides, and Tian Shan. Many of the sites show evidence of simultaneous displacement anomalies and this observation is interpreted as a reflection of the plate-wide propagation of a tectonic pressure pulse towards the end of 2012.
We report the results of 3-years of Radon-222 monitoring in six show caves across Europe, selecte... more We report the results of 3-years of Radon-222 monitoring in six show caves across Europe, selected with the feature of having only one, or no natural entrance, defined as dead-end caves. The caves are located in Spain, Slovakia, Slovenia, and Czechia. The consecutive monitoring was performed between January 2017 and January 2020. Continuous measurements of the radon activity concentration using spectrometry detection and analysis of the α-particles of 222Rn progeny were performed. Meteorological parameters influencing gas flow were recorded inside and outside of the caves. Although the radon activity concentrations differed from one cave to another, all six of the studied caves revealed very similar trends, showing evident seasonal variability with higher values in summer and lower values in winter. The measured values of radon activity concentrations ranged between 633 and 26,785 Bq/m3. The temperature differences between the inside and outside of the caves is the main radon moveme...
Izvle~ek UDK: 551.44(77) Stanka [ebela & Randall C. Orndorff & David J. Weary: Geolo{ke zakonitos... more Izvle~ek UDK: 551.44(77) Stanka [ebela & Randall C. Orndorff & David J. Weary: Geolo{ke zakonitosti pri razvoju jam v osrednjem delu ju'nih Ozarkov, Missouri, ZDA Podro~je Ozarkov v Missouriju je eden najve~jih kra{kih terenov v ZDA. Prevladujo~o litologijo predstavljajo kambrijski in ordovicijski dolomiti in pe{~enjaki. [tevilne, ve~inoma horizontalne jame in veliki kra{ki izviri so zna~ilnosti krasa Ozarkov. Od oktobra 1996 do vklju~no maja 1999 smo obiskali 23 kra{kih jam, za 18 jam v osrednjem delu ju'nih Ozarkov smo naredili geolo{ke karte. Za ta ~lanek smo predstavili geologijo {tirih jam. Prevladujo~a geolo{ka zakonitost, ki vpliva na oblikovanje jam je vpad plasti in preferen~na plast stromatolitnega dolomita. Edina mo'na povezava med geolo{ko strukturo in smerjo jamskih rovov je smer rovov sever-jug in smer razpok sever-jug.
Na primeru treh odsekov rovov v Postojnski jami je bila proucevana njihova speleogeneza. Pokazalo... more Na primeru treh odsekov rovov v Postojnski jami je bila proucevana njihova speleogeneza. Pokazalo se je, da so oblikovane po lezikah, zdrsnih lezikah in veznih razpokah.Ugodnost le nekaterih lezik in zdrsnih lezik za speleogenezo je v njihovi povezanosti v penetrativno efektivno poroznost v dolocenem strukturnem bloku. In 3 examples of passage parts from Postojnska Jama their speleogenesis was studied. It was shown that they are formed along bedding planes, moved bedding planes and connective fissures. The advantage for speleogenesis of some bedding planes and moved bedding planes is represented with their connection into penetrative effective porosity in specific structural block.
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