The Podpeč Limestone (also known as Predole Beds) is a geological formation of Pliensbachian-Earliest Toarcian (Early Jurassic) age in southern and southwestern Slovenia, including South-West of Ljubljana or nearby Mount Krim, with other isolated locations such as in the Julian Alps.[1][2] This unit represents the major depositional record of the Adriatic Carbonate platform (and more or less to the margin of Greater Adria), being known for its shallow marine-lagoon deposits and its bivalve biota, that are abundant enough to give the vulgar name to this unit sometimes in literature as the "Lithiotis Horizon".[2][3] Is a regional ecological equivalent to the Veneto Rotzo Formation, the Montenegro Budoš Limestone or the Moroccan Aganane Formation.[4] Its regional equivalents include the hemipelagic Krikov Formation at the Tolmin basin.[5][6]
| Podpeč Limestone | |
|---|---|
| Stratigraphic range: Pliensbachian-Early Toarcian | |
 Podpeč area with the limestone in the background | |
| Type | Geological formation |
| Underlies | Perbla Formation |
| Area | Ljubljana |
| Thickness | >75 m |
| Lithology | |
| Primary | limestone |
| Location | |
| Location | Central Slovenia |
| Coordinates | 46°00′N 14°24′E / 46.0°N 14.4°E |
| Region | Dinaric Carbonate Platform |
| Country |  Slovenia |
| Type section | |
| Thickness at type section | ~75 m (246 ft) |
  Podpeč Limestone (Slovenia) | |
Cultural Importance
edit
This limestone has been used since Roman times in Slovenia, with artefacts crafted from this stone including funerary markers, altars, and boundary stones. The limestone was transported along the Ljubljanica river to Emona (now Ljubljana), where it featured prominently in major Roman structures. When the Roman Empire fell in the 5th century AD, stone extraction at Podpeč ceased for centuries.[2][7][8]
Archaeological findings in Emona showed this limestone was valued for its durability, in contrast to the less resilient sandstones, like the ones from Ljubljana Castle. It was also favored due to the accessibility of the quarries by redirecting the Ljubljanica River within a kilometer, facilitating transport.[2][8]
Interest in Podpeč Limestone remained minimal until around 1850, aside from a few historical buildings, such as a church portal from the 15th century. However, the stone gained popularity by the late 19th and early 20th centuries, leading to its use in various architectural elements like sills, lintels, and door frames in Ljubljana. It also became popular for monuments, fountains, and religious artifacts. The quarry remained active until production ceased in 1967, with the limestone also crushed for roadwork and shipped as blocks for stonecutting workshops.[2][8]
A notable user of this limestone was by the Slovenian architect Jože Plečnik, who applied them in the construction of several iconic structures in Ljubljana, including the Central Stadium, the Faculty of Natural Sciences and Technology, the National University Library, and various churches and altars. Other notable buildings featuring this stone include the Triglav Insurance Company Palace, sections of the Slovenian Parliament, and Ljubljana skyscraper.[2][8]
Paleoenvironment
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In Slovenia, the northeastern margin of the Adriatic Platform displays a range of Lower Jurassic carbonate deposits, prominently seen from Tolmin through Vrhnika, Novo Mesto, Krško, and into the Gorjanci region. These deposits are characterized by well-layered, dark platform carbonates, including interbedded mudstones, fossiliferous wackestones, oolitic grainstones, and later-stage diagenetic dolomites.[6] This Slovenian carbonate sequence is comparable to those observed in adjacent regions like Croatia and Bosnia.[6]
Throughout the wider Adriatic Carbonate Platform in Slovenia and beyond, the transition to Toarcian carbonates shows a reduction in significant fossils, a trend also noted in the Croatian and Bosnian sections.[6]
The Podpeč type profile revelated a 75-meter-thick limestone sequence rich in diverse types, including micritic, bioclastic, and ooidal limestone, interspersed with marl, specially within the lower layers, while tectonic activity is evident in the upper sections.[2] The distinctive dark grey to black limestone is highly valued for its aesthetic appeal, marked by white fossilized bivalves. This limestone, known as a "lumachella," formed under low-oxygen lagoonal conditions and contains abundant Lithiotis-type bivalves. Faces similar to those at Preserje near Borovnica indicate littoral zones with alternating subtidal and supratidal conditions, similar to the present-day Bahamas, with occasional high-energy oolitic limestone beds reflecting dynamic water flow.[9]
During the Lower Jurassic, southern Slovenia was part of the Dinaric Carbonate Platform, a shallow marine environment adjacent to the deep-sea Slovenian Basin to the north and stretching into what is now Croatia. The Julian Carbonate Platform lay further north across the basin. Due to the depth of the basin, species exchange between the Dinaric and Julian platforms was unlikely. However, the narrowing of the Slovenian Basin near central Soča Valley may have allowed direct contact between these platforms.[4][10]
Within the Dinaric Platform, shallow, turbulent waters shaped the limestone formations, forming breccias and oolitic sands that built up into beaches and dunes. Coral reefs served as barriers, protecting southern lagoonal areas rich in organic material, where limited oxygen levels facilitated the formation of bituminous rock layers. Salinity fluctuations, caused by alternating drought and rainfall periods, drove dolomitization, transforming the sediments. The presence of tropical fossils, including Mytilus-like bivalves and land plants, as well as rare coal beds, indicates intermittent swampy land islands.[4][11][12]
The fossil record across these layers is diverse, preserving bivalves, gastropods, brachiopods, foraminifera, algae, and occasional coral. A rimmed carbonate platform model is proposed for the Podpeč region, positioning it near the oolitic platform margin with a sheltered lagoon landward characterized by low-energy, mud-rich limestone. Neighboring areas like Trnovski Gozd share these conditions, while sites like Kočevje and Suha krajina reveal lithiotid dolomite layers, breccias, and coal-bearing deposits from marshy environments. While some propose a ramp model, evidence such as cortoids and aggregate grains, as well as frequent emersion events, supports the rimmed platform model and a stable paleogeographic setting.[12]
This area, part of the ancient Adriatic plate, once lay in a tropical belt at lower latitudes, later shifting northward to its present location.[11]
Fossil Content
editColor key
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Notes Uncertain or tentative taxa are in small text; |
Foraminifera
edit| Genus | Species | Location | Material | Notes | Images |
|---|---|---|---|---|---|
| Aeolisaccus[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the Earlandiidae family | |
| Agerina[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the Cornuspiridae family | |
| Amijiella[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the Hauraniidae family | |
| Bosniella[1] |
|
|
Calcareous Skeletons | A foraminifer of the Biokovinidae family | |
| Coronipora[1] |
|
|
Calcareous Skeletons | A foraminifer of the Trocholinidae family | |
| Duotaxis[1] |
|
|
Calcareous Skeletons | A foraminifer of the Verneuilinoidinae family | |
| Everticyclammina[1] |
|
|
Calcareous Skeletons | A foraminifer of the Everticyclamminidae family. | |
| Glomospira[1] |
|
|
Calcareous Skeletons | A foraminifer of the family Ammodiscidae. | |
| Haurania[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the family Hauraniinae. | |
| Involutina[13][14][15] |
|
|
Calcareous Skeletons | A foraminifer of the Involutinidae family | |
| Lituosepta[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the Mesoendothyridae family. | |
| Lituolipora[1] |
|
|
Calcareous Skeletons | A foraminifer of the Mayncinidae family | |
| Meandrovoluta[1] |
|
|
Calcareous Skeletons | A foraminifer of the Cornuspiridae family | |
| Mesoendothyra[1] |
|
|
Calcareous Skeletons | A foraminifer of the Mesoendothyridae family. | |
| Orbitopsella[1][13][14] |
|
|
Calcareous Skeletons | A foraminifer of the Mesoendothyridae family. | |
| Ophtalmidium[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the family Ophthalmidiidae. | |
| Paleomayncina[1][16] |
|
|
Calcareous Skeletons | A foraminifer of the Planiseptinae family. | |
| Planisepta[1][13] |
|
|
Calcareous Skeletons | A foraminifer of the Planiseptinae family. | |
| Pseudocyclammina[1][13][14] |
|
|
Calcareous Skeletons | A foraminifer of the Pfenderinidae family. | |
| Pseudopfenderina[1] |
|
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Calcareous Skeletons | A foraminifer of the Pseudopfenderininae family. | |
| Siphovalvulina[1] |
|
|
Calcareous Skeletons | A foraminifer of the Pfenderinidae family. |
Sponges
edit| Genus | Species | Stratigraphic position | Material | Notes | Images |
|---|---|---|---|---|---|
| Stromatomorpha[17] |
|
|
Colonial Imprints | A Chaetetidan Demosponge, member of Anthaspidellidae. |
Anthozoa
edit| Genus | Species | Stratigraphic position | Material | Notes | Images |
|---|---|---|---|---|---|
| Archaeosmiliopsis[17] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Zardinophyllidae. | |
| Cladophyllia[18] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Cladophylliidae. | |
| Cuifastraea[17] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Cuifastraeidae. | |
| Dichopsammia[18] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Dendrophylliidae. | |
| Epismilia[17] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Zardinophyllidae. | |
| Heterastraea[18][17] |
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Colonial Imprints | A Scleractinian Coral, member of Oppelismiliidae. | |
| Hispaniastraea[18] |
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|
Colonial Imprints | A Scleractinian Coral, member of Hispaniastraeidae. | |
| Intersmilia[18] |
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|
Colonial Imprints | A Scleractinian Coral, member of Intersmiliidae. | |
| Phacelophyllia[18] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Oppelismiliidae. | |
| Rhabdophyllia[18] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Montlivaltiidae. |  |
| Siderosmilia[17] |
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Colonial Imprints | A Scleractinian Coral, member of Siderastreidae. | |
| Stylophyllopsis[19] |
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Colonial Imprints | A Scleractinian Coral, member of Stylophyllidae | |
| Thecactinastraea[18][17] |
|
|
Colonial Imprints | A Scleractinian Coral, member of Oppelismiliidae. |
Brachiopoda
edit| Genus | Species | Stratigraphic position | Material | Notes | Images |
|---|---|---|---|---|---|
| Hesperithyris[20] |
|
|
Isolated Shells | A Terebratulidan brachiopoda, member of Hesperithyrididae. | |
| Lychnothyris[20] |
|
|
Isolated Shells | A Terebratulidan brachiopoda, member of Plectoconchidae. Typical Mediterranean region taxon in the Pliensbachian, the main Branchiopod locally associated with the Lithiotids facies, where they formed rare mass occurrences at discrete intervals.[21] |
Mollusca
editUnidentified members of Pectinidae, Megalodontidae or Nerineidae are known from several locations.[9][14]
| Genus | Species | Stratigraphic position | Material | Notes | Images |
|---|---|---|---|---|---|
| Astarte[20] |
|
|
Isolated Shells | A clam, member of Astartidae inside Carditida. | |
| Cochlearites[4][20][14] |
|
|
|
An oyster, member of Plicatostylidae inside Ostreida. A large bivalve, with a subequivalved shell, up to 60–70 cm high. It is one of the Three main bivalves recovered on the Lithiotis Facies, with its accumulations generally overlying megalodontid coquinas.[22] | |
| Gervilleioperna[4][20][14] |
|
|
Isolated Shells | An oyster, member of Plicatostylidae inside Ostreida. | |
| Lithioperna[4][20][14] |
|
|
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An oyster, member of Plicatostylidae inside Ostreida. | |
| Lithiotis[4][20] |
|
|
|
An oyster, member of Plicatostylidae inside Ostreida. Large, large and aberrant bivalves, it's accumulation have had different denominations on literature, such as banks, bioherms, biostromes, bivalve reefs or bivalve mounds.[22] | |
| Manticula[4] |
|
|
Isolated Shells | An oyster, member of the family Pergamidiidae inside Ostreida. | |
| Mytiloperna[4] |
|
|
Isolated Shells | An oyster, member of the family Malleidae inside Ostreida. | |
| Opisoma[4][20] |
|
|
Isolated Shells | A clam, member of Astartidae inside Carditida. Is considered a genus that evolved from shallow burrowing ancestors, becoming a secondarily semi-infaunal edgewise recliner adapted to photosymbiosis.[23] | |
| Pachyrisma[4][20] |
|
|
Isolated Shells | A clam, member of Megalodontidae inside Megalodontida. | |
| Pecten[20][14] |
|
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Isolated Shells | A scallop, member of the family Pectinidae inside Pectinida |  |
"Algae"
edit| Genus | Species | Location | Material | Notes | Images |
|---|---|---|---|---|---|
| Aeolissacus[20] |
|
|
Calcified Thalli | A Possible Green Algae of the family Dasycladaceae. | |
| Bacinella[17] |
|
|
Calcified specimens | A Cyanobacterial Alga of the family Garwoodiaceae | |
| Thaumatoporella[17] |
|
|
Calcified Thalli | A Green alga of the Thaumatoporellales group | |
| Palaeodasycladus[24] |
|
|
Calcified Thalli | A Green Algae of the family Dasycladaceae. A reefal algae usually found in carbonate settings along all the Mediterranean | |
| Solenopora[17] |
|
|
Calcified specimens | A Red Alga of the family Solenoporaceae |
See also
edit- Rotzo Formation, Italy
- Marne di Monte Serrone, Italy
- Calcare di Sogno, Italy
- Aganane Formation, Morocco
- Tafraout Group, Morocco
- Budoš Limestone, Montenegro
- Cañadón Asfalto Formation, Argentina
- Los Molles Formation, Argentina
- Mawson Formation, Antarctica
- Kandreho Formation, Madagascar
- Kota Formation, India
- Cattamarra Coal Measures, Australia
References
edit- ^ a b c d e f g h i j k l m n o p q r s t u Gale, Luka (30 December 2014). "Lower Jurassic foraminiferal biostratigraphy of Podpeč Limestone (External Dinarides, Slovenia)". Geologija. 57 (2): 119–146. doi:10.5474/geologija.2014.011. ISSN 0016-7789.
- ^ a b c d e f g Kramar, S.; Bedjanič, M.; Mirtič, B.; Mladenović, A.; Rožič, B.; Skaberne, D.; Gutman, M.; Zupančič, N.; Cooper, B. (10 June 2014). "Podpeč limestone: a heritage stone from Slovenia". Geological Society, London, Special Publications. 407 (1): 219–231. doi:10.1144/sp407.2. ISSN 0305-8719.
- ^ Vlahović, Igor; Tišljar, Josip; Velić, Ivo; Matičec, Dubravko (2002). "The Karst Dinarides are Composed of Relics of a Single Mesozoic Platform: Facts and Consequences". Geologia Croatica. 55 (2): 171–183. doi:10.4154/gc.2002.15. ISSN 1330-030X.
- ^ a b c d e f g h i j k Buser, Stanko; Debeljak, Irena (30 December 1995). "Lower Jurassic beds with bivalves in south Slovenia". Geologija. 37/38 (1): 23–62. doi:10.5474/geologija.1995.001. ISSN 0016-7789.
- ^ Rožič, Boštjan (1 September 2009). "Perbla and Tolmin formations: revised Toarcian to Tithonian stratigraphy of the Tolmin Basin (NW Slovenia) and regional correlations". Bulletin de la Société Géologique de France. 180 (5): 411–430. doi:10.2113/gssgfbull.180.5.411. ISSN 1777-5817.
- ^ a b c d Dragičević, Ivan; Velić, Ivo (2002). "The Northeastern Margin of the Adriatic Carbonate Platform Article Sidebar". Geologia Croatica. 55 (2): 185–232. doi:10.4154/gc.2002.16. ISSN 1330-030X.
- ^ BRAJKOVIČ, Rok; GALE, Luka; DJURIĆ, Bojan (22 July 2022). "Multi-method study of the Roman quarry at Podpeč sedimentary succession and stone products". Geologija. 65 (1): 101–121. doi:10.5474/geologija.2022.007. ISSN 0016-7789.
- ^ a b c d Vesel, J.; Škerlj, J.; Čebulj, A. (1975). "Freestone quarried in Slovenia". Geologija. 18 (1): 243–258.
- ^ a b Ogorelec, Bojan (27 December 2009). "Lower Jurassic beds at Preserje near Borovnica (Central Slovenia)". Geologija. 52 (2): 193–204. doi:10.5474/geologija.2009.019. ISSN 0016-7789.
- ^ Debeljak, Irena (30 December 1997). "Lithiotid Bivalves in Slovenia and Their Mode of Life". Geologija. 40: 11–64. doi:10.5474/geologija.1997.001. ISSN 0016-7789.
- ^ a b Gale, Luka (29 December 2015). "Microfacies characteristics of the Lower Jurassic lithiotid limestone from northern Adriatic Carbonate Platform (central Slovenia)". Geologija. 58 (2): 121–138. doi:10.5474/geologija.2015.010. ISSN 0016-7789.
- ^ a b Dozet, Stevo (30 December 1998). "Lower Jurassic dolomite-limestone succession with coal in the Kočevski Rog and correlation with neighbouring areas (SE Slovenia)". Geologija. 41: 71–101. doi:10.5474/geologija.1998.004. ISSN 0016-7789.
- ^ a b c d e f g h i j Dozet, S. (2009). "Lower Jurassic carbonate succession between Predole and Mlačevo, Central Slovenia". Materials and Geoenvironment. 56 (2): 164–193. S2CID 211559009.
- ^ a b c d e f g h Dozet, S. (2009). "Lower Jurassic carbonate succession between Predole and Mlačevo, Central Slovenia". Materials and Geoenvironment. 56 (2): 164–193.
- ^ Radoicic, Rajka; Jovanovic, Divna (2011). "Involutina farinacciae Bronnimann & Koehn-Zaninetti 1969, a marker for the Middle Liassic in basinal and some platform facies of Mediterranean and near east areas: The discussion concerning the paleogeography of Montenegro-Albania border region (the Scutari-Pec lineament)". Geoloski Anali Balkanskoga Poluostrva (72): 47–61. doi:10.2298/gabp1172047r. ISSN 0350-0608.
- ^ Fugagnoli, Anna (2004). "Trophic regimes of benthic foraminiferal assemblages in Lower Jurassic shallow water carbonates from northeastern Italy (Calcari Grigi, Trento Platform, Venetian Prealps)". Palaeogeography, Palaeoclimatology, Palaeoecology. 205 (1–2): 111–130. doi:10.1016/j.palaeo.2003.12.004. ISSN 0031-0182.
- ^ a b c d e f g h i j Turnsek, D.; Kosir, A. (2000). "Early Jurassic corals from Krim Mountain, Slovenia". Razprave Slovenska Akademija Znanosti in Umetnosti, Razred za Naravoslovne Vede, IV. 41 (1): 81–113.
- ^ a b c d e f g h Turnsek, D.; Buser, S.; Debeljak, I. (2003). "Liassic coral patch reef above the "Lithiotid Limestone" on Trnovski Gozd Plateau, west Slovenia". Razprave Slovenska Akademija Znanosti in Umetnosti, Razred za Naravoslovne Vede. 44 (1): 285–331.
- ^ Turnsek, D.; Buser, S. (1999). "Stylophyllopsis veneta (Airaghi), a Liassic coral from the northern Dinaric Carbonate Platform (Slovenia)". Profil. 16 (1): 173–180.
- ^ a b c d e f g h i j k Geyer, O. F. (1977). "Die "Lithiotis-Kalke" im Bereich der unterjurassischen Tethys [The "Lithiotis Limestones" in the Lower Jurassic Tethys realm]". Neues Jahrbuch fuer Geologie und Palaeontologie, Abhandlungen. 153 (3): 304–340.
- ^ Bassi, Davide; Angiolini, Lucia; Nebelsick, James H.; Posenato, Renato (2024). "Success and demise of exceptionally preserved terebratulide brachiopod accumulations in a Jurassic (early Pliensbachian) tropical lagoonal setting (Southern Alps, Italy): Brachiopod response to environmental changes". Palaeogeography, Palaeoclimatology, Palaeoecology. 648: 112262. Bibcode:2024PPP...64812262B. doi:10.1016/j.palaeo.2024.112262. ISSN 0031-0182.
- ^ a b Posenato, R.; Masetti, D. (2012). "Environmental control and dynamics of Lower Jurassic bivalve build-ups in the Trento Platform (Southern Alps, Italy)". Palaeogeography, Palaeoclimatology, Palaeoecology. 361 (2): 1–13. Bibcode:2012PPP...361....1P. doi:10.1016/j.palaeo.2012.07.001. Retrieved 3 January 2022.
- ^ Posenato, R. (2013). "Opisoma excavatum Boehm, a Lower Jurassic photosymbiotic alatoform-chambered bivalve". Lethaia. 46 (2): 424–437. Bibcode:2013Letha..46..424P. doi:10.1111/let.12020. Retrieved 3 January 2022.
- ^ Sokač, Branko (29 December 2001). "Lower and Middle Liassic Calcareous Algae (Dasycladales) from Mt. Velebit (Croatia) and Mt. Trnovski Gozd (Slovenia) with Particular Reference to the Genus Palaeodasycladus (PIA, 1920) 1927 and Its Species". Geologia Croatica. 54 (2): 133–257. doi:10.4154/gc.2001.07. ISSN 1330-030X.