The Forni Dolostone, also known as the Dolomia di Forni, is a

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...

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Norian The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic defi ...

, or

Alaunian The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic defi ...

in the local

biochronology In paleontology, biochronology is the correlation in time of biological events using fossils. In its strict sense, it refers to the use of assemblages of fossils that are not tied to stratigraphic sections (in contrast to biostratigraphy, where th ...

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dolomite Dolomite may refer to: *Dolomite (mineral), a carbonate mineral *Dolomite (rock), also known as dolostone, a sedimentary carbonate rock *Dolomite, Alabama, United States, an unincorporated community *Dolomite, California, United States, an unincor ...

geological formation in northeastern

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

. The formation was deposited in a

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') a ...

al to shallow marine

environment Environment most often refers to: __NOTOC__ * Natural environment, all living and non-living things occurring naturally * Biophysical environment, the physical and biological factors along with their chemical interactions that affect an organism or ...

.Dolomia di Forni
at

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Description

It represents deposition in an anoxic marine basin whose maximum depth was about , and was surrounded by the shallow water carbonate platform of the Dolomia Principale Formation. The Dolomia di Forni is composed mainly of dark, often

chert Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...

y, well-bedded dolostone that is frequently thinly laminated and sometimes slumped. Thicker laminae are graded and represent distal

turbidite A turbidite is the geologic deposit of a turbidity current, which is a type of amalgamation of fluidal and sediment gravity flow responsible for distributing vast amounts of clastic sediment into the deep ocean. Sequencing Turbidites were ...

s. The basinal facies preserving the tetrapod remains are composed mainly of distal turbidites and carbonate mud deposited by fallout.

Fossil content

The following fossils have been reported from the formation: ;Other reptiles * '' Langobardisaurus tonelloi''Muscio, 1997 * '' Megalancosaurus preonensis''Calzavara et al., 1981 * '' ?Drepanosaurus unguicaudatus'' ;Fish * '' Pseudodalatias barnstonensis'' * '' Sargodon tomicus'' * '' Thoracopterus martinisi''Tintori & Sassi, 1992 * '' ?Eopholidophorus forojuliensis'' * '' Holophagus sp.'' * '' Saurichthys sp.'' ;Arachnids * '' Friularachne rigoi''Dalla Vecchia & Selden, 2013 ;Crustaceans * '' Acanthochirana triassica'' * '' Antrimpos colettoi'' * '' A. noricus'' * '' Archaeopalinurus levis'' * '' Dusa denticulata'' * '' D. longipes'' * '' Microcaris minuta'' * '' Pseudocoleia mazzolenii'' * '' Rosenfeldia triassica'' * '' Glaessnericaris sp.'' * '' Glyphea sp.'' ;Flora * '' Brachyphyllum sp.'' * Coniferales indet.

References

{{reflist, 3

Bibliography

* F. M. Dalla Vecchia. 2019. ''Seazzadactylus venieri'' gen. et sp. nov., a new pterosaur (Diapsida: Pterosauria) from the Upper Triassic (Norian) of northeastern Italy. PeerJ 7(e7363) * F. M. Dalla Vecchia and P. A. Selden. 2013. A Triassic spider from Italy. Acta Palaeontologica Polonica 58:325-330 * F. M. Dalla Vecchia. 2004. An ''Eudimorphodon'' (Diapsida, Pterosauria) specimen from the Norian (Late Triassic) of north-eastern Italy. Gortania - Atti del Museo Friulano di Storia Naturale 25:47-72 * F. M. Dalla Vecchia. 2003. A review of the Triassic pterosaur record. Rivista del Museo Civico di Scienze Naturali "E. Caffi" Bergamo 22:13-29 * S. Renesto, F. M. Dalla Vecchia, and D. Peters. 2002. Morphological evidence for bipedalism in the Late Triassic prolacertiform reptile ''Langobardisaurus''. Senckenbergiana Lethaea 82:95-106 * F. M. Dalla Vecchia. 2000. A wing phalanx of a large basal pterosaur (Diapsida, Pterosauria) from the Norian (Late Triassic) of NE Italy. Bollettino della Societa Paleontologica Italiana 39(2):229-234 * S. Renesto. 2000. Bird-like head on a chameleon body: new specimens of the enigmatic diapsid reptile ''Megalancosaurus'' from the Late Triassic of Northern Italy. Rivista Italiana di Paleontologia e Stratigrafia 106:157-180 * G. Muscio. 1997. Preliminary note on a specimen of Prolacertiformes (Reptilia) from the Norian (Late Triassic) of Preone (Udine, north-eastern Italy). Gortania - Atti del Museo Friulano di Storia Naturale 18:33-40 * A. Garassino, G. Teruzzi, and F. Vecchia. 1996. The macuran decapod crustaceans of the Dolomia di Forni (Norian, Upper Triassic) of Carnia (Udine, NE Italy). Atti della Societa Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano 136(1):15-60 * F. Bizzarini and G. Muscio. 1995. Un nuovo rettile (Reptilia, Prolacertiformes) dal Norico di Preone (Udine, Italia Nordorientale). Nota preliminare new reptile (Reptilia, Prolacertiformes) from the Norian of Preone (Udine, N.E. Italy). Preliminary Note Gortania - Atti del Museo Friulano di Storia Naturale 16 (1994):67-76 * F. M. Dalla Vecchia. 1995. A new pterosaur (Reptilia, Pterosauria) from the Norian (Late Triassic) of Friuli (northeastern Italy). Preliminary note. Gortania - Atti del Museo Friulano di Storia Naturale 16:59-66 * A. Tintori and D. Sassi. 1992. ''Thoracopterus'' Bronn (Osteichthyes: Actinopterygii): a gliding fish from the Upper Triassic of Europe. Journal of Vertebrate Paleontology 12(3):265-283 * F. M. Dalla Vecchia. 1991. Note sulla stratigrafia, sedimentologia e paleontologia della Dolomia di Forni (Triassico Superiore) nella Valle del Rio Seazza (Preone, Friuli-Venezia Giulia) ote on the stratigraphy, sedimentology, and paleontology of the Dolomia di Forni (Upper Triassic) of the Rio Seazza Valley (Preone, Friuli-Venezia Giulia) Gortania - Atti del Museo Friulano di Storia Naturale 12(90):7-30 * F. M. Dalla Vecchia, G. Muscio, and R. Wild. 1989. Pterosaur remains in a gastric pellet from the Upper Triassic (Norian) of Rio Seazza Valley (Udine, Italy). Gortania - Atti del Museo Friuliano di Storia Naturale 10:121-132 * G. Pinna. 1988. Un nuovo esemplare giovanile di Drepanosaurus unguicaudatus del Norico di Val Preone (Udine) new juvenile specimen of Drepanosaurus unguicaudatus from the Norian of the Preone Valley, Udine Atti della Società Italiana di Scienze Naturali - Museo civico di Storia Naturale di Milano 128:80-84 * R. Wild. 1984. A new pterosaur (Reptilia, Pterosauria) from the Upper Triassic (Norian) of Fruili, Italy. Gortania - Atti del Museo Friulano di Storia Naturale 5:45-62 * M. Calzavara, G. Muscio, and R. Wild. 1981. ''Megalancosaurus preonensis'' n. g., n. sp., a new reptile from the Norian of Friuli, Italy. Gortania - Atti del Museo Friulano di Storia Naturale 2:49-64

External links

Gastric pellet
Geologic formations of Europe Triassic System of Europe Triassic Italy Norian Stage Dolomite formations Marl formations Lagoonal deposits Shallow marine deposits Paleontology in Italy