| Rotzo Formation | |
|---|---|
| Stratigraphic range: Early Pliensbachian ~[1] | |
 Schaff Kugela, with lower part exposing grey limestone | |
| Type | Geological formation |
| Unit of | Calcari Grigi Group |
| Sub-units | Tovel Member[2] |
| Underlies | Massone Oolitic Limestone |
| Overlies | |
| Area | Trento Platform |
| Thickness | 250 m |
| Lithology | |
| Primary | Lithified gray silty marl, gray grainstone, bioturbated/intraclastic/ooidal gray wackestone, mud banks and sand deposits.[3] |
| Other | Light-grey to yellowish-grey packstone with oolites, bioclasts, algal lumps, pellets, dasycladacean algae, foraminifera, lituolids, and miliolids |
| Location | |
| Location | Vicenza Province: Trentino-Alto Adige, Southern Alps |
| Coordinates | 45°42′N 11°06′E / 45.7°N 11.1°E |
| Approximate paleocoordinates | 32°06′S 16°42′E / 32.1°S 16.7°E |
| Region | Veneto |
| Country |  Italy |
| Type section | |
| Named for | Rotzo |
  Rotzo Formation (Italy) | |
The Rotzo Formation (also known in older literature as the Noriglio Grey Limestone Formation) is a geological formation in Italy, dating to roughly between 192 and 186 million years ago and covering the Pliensbachian stage of the Jurassic Period in the Mesozoic Era.[4] Has been traditionally classified as a Sinemurian-Pliensbachian Formation, but a large and detailed dataset of isotopic 13C and 87Sr/86Sr data, estimated the Rotzo Formation to span only over the Early Pliensbachian, bracketed between the Jamesoni-Davoei biozones, marked in the Loppio Oolitic Limestone–Rotzo Fm contact by a carbon isotope excursion onset similar to the Sinemu-Pliens boundary event, while the other sequences fit with the a warm phase that lasts until the Davoei biozone.[1] The Rotzo Formation represented the Carbonate Platform, being located over the Trento Platform and surrounded by the Massone Oolite (marginal calcarenitic bodies), the Fanes Piccola Encrinite (condensed deposits and emerged lands), the Lombadian Basin Medolo Group and Belluno Basin Soverzene Formation (open marine), and finally towards the south, deep water deposits of the Adriatic Basin.[5] The Pliensbachian Podpeč Limestone of Slovenia, the Aganane Formation & the Calcaires du Bou Dahar of Morocco represent regional equivalents, both in deposition and faunal content.
Fossil prosauropod tracks have been reported from the formation.[6] This formation was deposited within a tropical lagoon environment, similar to modern Bahamas which was protected by oolitic shoals and bars from the open deep sea located to the east (Belluno Basin) and towards the west (Lombardia Basin). It is characterized by a rich paleontological content. It is notable mostly thanks to its great amount of big aberrant bivalves, among which is the genus Lithiotis, described in the second half of the nineteenth century. The unusual shape of Lithiotis and Cochlearites shells, extremely elongated and narrow, characterized by a spoon-like body space placed in a high position, rarely preserved, seems to suggest their adaptation to soft and muddy bottoms with a high sedimentation rate.[7] The Bellori outcrop displays about 20 m of limestones with intercalated clays and marls rich in organic matter and sometimes fossil wood (coal) and amber. The limestones are well stratified, with beds 10 cm to more than one metre thick, whereas the clayey levels range between 3 and 40 cm in thickness.[8][9]
- ^ a b Franceschi, M.; Dal Corso, J.; Posenato, R.; Roghi, G.; Masetti, D.; Jenkyns, H. C. (2014). "Early Pliensbachian (Early Jurassic) C-isotope perturbation and the diffusion of the Lithiotis Fauna: Insights from the western Tethys". Palaeogeography, Palaeoclimatology, Palaeoecology. 410 (1): 255–263. Bibcode:2014PPP...410..255F. doi:10.1016/j.palaeo.2014.05.025. Retrieved 12 November 2021.
- ^ Castellarin, A.; Picotti, V.; Cantelli, L.; Claps, M.; Trombetta, L.; Selli, L.; Carton, A.; Borsato, A.; Daminato, F.; Nardin, M.; Santuliana, E.; Veronese, L.; Bollettinari, G. (2005). "Note Illustrative della Carta Geologica d'Italia alla scala 1:50.000, Foglio 080 Riva del Garda". Dipartimento Difesa del Suolo, Servizio Geologico d'Italia. 56 (2): 145. Retrieved 24 January 2022.
- ^ "PBDB".
- ^ Broglio Loriga, C.; Neri, C. (1976). "Aspetti paleobiologici e paleogeografici delle facies "Lithiotis" (Giurese inf.)". Rivista Italiana di Paleontologia e Stratigrafia. 82 (1): 651–151.
- ^ Masetti, D.; Fantoni, R.; Romano, R.; Sartorio, D.; Trevisani, E. (2012). "Tectonostratigraphic evolution of the Jurassic extensional basins of the eastern southern Alps and Adriatic foreland based on an integrated study of surface and subsurface data". AAPG Bulletin. 96 (11): 2065–2089. Bibcode:2012BAAPG..96.2065M. doi:10.1306/03091211087. Retrieved 12 November 2021.
- ^ Mietto, P.; Roghi, G.; Zorzin, R. (2000). "Le impronte di dinosauri liassici dei Monti Lessini Veronesi [The Liassic dinosaur tracks from the Veronese Monti Lessini]". Bollettino del Museo Civico di Storia Naturale di Verona. Geologia Paleontologia Preistoria. 24 (2): 55–72.
- ^ Masseti, D.; Posenato, R.; Bassi, D.; Fungagnoli, A. (2005). "The Rotzo Formation (Lower Jurassic) at the Valbona Pass (Vicenza Province)". IRIS Università degli Studi di Ferrara. 31 (5): 35–56. Retrieved 3 January 2022.
- ^ Neri, Mirco; Papazzoni, Cesare Andrea; Vescogni, Alessandro; Roghi, Guido (2015). "Cyclical variation in paleoenvironments of the Rotzo formation (Lower Jurassic, Lessini Mts., N Italy)". STAMPA. 33 (1): 74–75.
- ^ Urban, I. (2017). "Petrografia e geochimica delle ooliti del Giurassico inferiore della Piattaforma di Trento". Area 04 - Scienze della Terra > GEO/02 Geologia Stratigrafica e Sedimentologica. 1 (1): 1–203. Retrieved 3 January 2022.