San Salvatore Dolomite

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San Salvatore Dolomite
Stratigraphic range:
Late Anisian (Illyrian)
Picswiss TI-16-02.jpg
Monte San Salvatore, which is mostly formed by San Salvatore Dolomite
Type Geological formation
Sub-unitsRasa Dolomite
Underlies Besano Formation, Pizzella Marls
Overlies Bellano Formation, Fenera Annunziata Sandstone, Pissone Dolomite
Lithology
Primary Dolomite
Location
Region Lombardy, Piedmont,
Ticino
CountryFlag of Italy.svg  Italy
Flag of Switzerland (Pantone).svg   Switzerland
ExtentSouthwestern Limestone Alps
Type section
Named for Monte San Salvatore
Switzerland relief location map.jpg
Pink ff0080 pog.svg
San Salvatore Dolomite (Switzerland)

The San Salvatore Dolomite, sometimes known as the Salvatore Dolomite or San Salvatore Formation, is a Middle Triassic (late Anisian) geological formation in Switzerland and Italy. The primarily lithology is micritic dolomite with a high proportion of algal mounds (stromatolites). [1] It corresponds to a thick warm-water carbonate platform on the northern edge of an island in what is now the Po Plain. This formation and its local equivalents are common in the hills around Lake Maggiore, Varese, and Lugano, preserving fossils of marine invertebrates such as ammonoids, gastropods, and bivalves. At its southernmost extent on Monte San Giorgio, only the lower part of the San Salvatore Dolomite is preserved. The middle and upper parts are replaced by the Besano Formation, San Giorgio Dolomite, and Meride Limestone, which were deposited in a deeper and more anoxic basin between carbonate platforms. [2] [3] [4] [5]

Related Research Articles

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<i>Cymbospondylus</i> Extinct genus of reptiles

Cymbospondylus is an extinct genus of large ichthyosaurs, of which it is among the oldest representatives, that lived from the Lower to Middle Triassic in what are now North America and Europe. The first known fossils of this taxon are a set of more or less complete vertebrae which were discovered in the 19th century in various mountain ranges of Nevada, in the United States, before being named and described by Joseph Leidy in 1868. It is in the beginning of the 20th century that more complete fossils were discovered through several expeditions launched by the University of California, and described in more detail by John Campbell Merriam in 1908, thus visualizing the overall anatomy of the animal. While many species have been assigned to the genus, only five are recognized as valid, the others being considered synonymous, doubtful or belonging to other genera. Cymbospondylus was formerly classified as a representative of the Shastasauridae, but more recent studies consider it to be more basal, view as the type genus of the Cymbospondylidae.

<i>Ticinosuchus</i> Extinct species of reptile

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<span class="mw-page-title-main">Monte San Giorgio</span> Mountain in Switzerland and Italy

Monte San Giorgio is a Swiss mountain and UNESCO World Heritage Site near the border between Switzerland and Italy. It is part of the Lugano Prealps, overlooking Lake Lugano in the Swiss Canton of Ticino.

<i>Ticinepomis</i> Extinct genus of coelacanths

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<i>Besanosaurus</i> Genus of Triassic ichthyosaur

Besanosaurus is a extinct genus of Middle Triassic ichthyosaur from Monte San Giorgio of Italy and Switzerland, containing the single species B. leptorhynchus. Besanosaurus was named by Cristiano Dal Sasso and Giovanni Pinna in 1996, based on the nearly complete flattened skeleton BES SC 999, the holotype specimen. This skeleton is preserved across multiple thin rock slabs spanning 3.5 by 4 metres when assembled and took thousands of hours to prepare. Additional specimens from Monte San Giorgio that have previously been considered separate genera, including a partial skull named Mikadocephalus and a well-preserved, largely complete skeleton, have been reinterpreted as additional specimens of Besanosaurus. Putative specimens of Besanosaurus have been discovered in the Norwegian archipelago of Svalbard and Germany, although their attribution to this genus remains disputed.

<i>Serpianosaurus</i> Extinct genus of reptiles

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<i>Ctenognathichthys</i> Extinct genus of fishes

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<i>Acentrophorus</i> Extinct genus of fishes

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<i>Colobodus</i> Extinct genus of fishes

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<i>Meridensia</i> Extinct genus of fishes

Meridensia is an extinct genus of prehistoric ray-finned fish that lived during the Anisian and Ladinian ages of the Middle Triassic epoch in what is now southern Switzerland and northern Italy. Fossils were recovered from the Besano Formation of Monte San Giorgio and Besano area at the Swiss-Italian boundary.

<i>Wimanius</i> Extinct genus of reptiles

Wimanius is a genus of ichthyosaur from the Middle Triassic of Switzerland, containing a single species, Wimanius odontopalatus. It was described by Michael Maisch and Andreas Matzke in 1998 based on an incomplete skull from Monte San Giorgio, a mountain on the Swiss-Italian border. Wimanius possesses teeth on its palate, though whether they were located on the palatine or pterygoid is disputed. Other features of Wimanius include a large orbit and jugals with two rami of similar lengths. Different phylogenetic placements of Wimanius have been recovered by different studies, including it being a mixosaurid relative or a merriamosaur, and a monotypic family, Wimaniidae has been named for it. However, its validity has also been questioned, and synonymy with various other genera has been proposed. The only specimen of Wimanius come from the Besano Formation. During the Anisian, this region was a lagoon populated by a wide variety of marine life, including a variety of other ichthyosaurs.

<span class="mw-page-title-main">Wetterstein Formation</span> Regional geologic formation in the Northern Limestone Alps and Western Carpathians

The Wetterstein Formation is a regional geologic formation of the Northern Limestone Alps and Western Carpathians extending from southern Bavaria, Germany in the west, through northern Austria to northern Hungary and western Slovakia in the east. The formation dates back to the Ladinian to Carnian stages of the Late Triassic. The formation is named after the Wetterstein Mountains in southern Germany and northwestern Austria. The center of its distribution, however, is in the Karwendel Mountains. It occurs in the Northern and Southern Limestone Alps and in the Western Carpathians.

<i>Eusaurosphargis</i> Extinct genus of reptiles

Eusaurosphargis is an extinct genus of a diapsid reptile, known from the Middle Triassic Besano Formation of northern Italy and Prosanto Formation of south-eastern Switzerland. It contains a single species, Eusaurosphargis dalsassoi. It was a small reptile, measuring 20 cm (7.9 in) long.

The Besano Formation is a geological formation in the southern Alps of northwestern Italy and southern Switzerland. This formation, a thin but fossiliferous succession of dolomite and black shale, is famous for its preservation of Middle Triassic (Anisian–Ladinian) marine life including fish and aquatic reptiles. It is exposed in the Monte San Giorgio and Besano area. It is among the formations responsible for the area being designated as a UNESCO World Heritage Site. In Switzerland, it is also known as the Grenzbitumenzone. The Anisian-Ladinian boundary lies in the upper part of the Besano Formation.

<i>Acronemus</i> Enigmatic extinct genus of cartilaginous fish

Acronemus is an extinct genus of euselachian from the Middle Triassic of Switzerland. It is an enigmatic genus with uncertain relations to other groups. Though originally placed within Ctenacanthiformes, it is now considered Euselachii incertae sedis, due to its mixture of features similar to hybodontiforms and neoselachians. Originally, teeth from this genus were attributed to "Acrodus bicarinatus" while fin spines were named "Nemacanthus tuberculatus". Associated material showed they were the same animal, with the older specific epithet (tuberculatus) taking precedence. The euselachian was given the new genus Acrocnemus, containing a single species. Acronemus is found in the Anisian-age Grenzbitumenzone of Monte San Giorgio. It was a small animal measuring 30–35 cm (0.98–1.15 ft) long. A 2018 study considered it to be closely related to the early Carboniferous genus Tristychius as part of the family Tristychiidae as a basal euselachian, with hybodonts more closely related to neoselachians than to Tristychiidae.

<i>Marcopoloichthys</i> Extinct genus of fishes

Marcopoloichthys is an extinct genus of marine teleosteomorph ray-finned fish known from the Middle and Late Triassic of the former Tethys Ocean. It is the only genus in the family Marcopoloichthyidae. It was originally described based on specimens from both Italy and China, hence the name Marcopoloichthys, which references the medieval Venetian merchant Marco Polo, who traveled from Italy to China.

References

  1. Berra, Fabrizio; Galli, Maria Teresa; Reghellin, Federico; Torricelli, Stefano; Fantoni, Roberto (2009-05-18). "Stratigraphic evolution of the Triassic–Jurassic succession in the Western Southern Alps (Italy): the record of the two-stage rifting on the distal passive margin of Adria". Basin Research. 21 (3): 335–353. Bibcode:2009BasR...21..335B. doi:10.1111/j.1365-2117.2008.00384.x. hdl: 2434/48580 . ISSN   1365-2117. S2CID   128904701.
  2. Bernasconi, Stefano Michele (1991). Geochemical and microbial controls on dolomite formation and organic matter production/preservation in anoxic environments: a case study from the Middle Triassic Grenzbitumenzone, Southern Alps (Ticino, Switzerland). ETH Zurich Dissertation (Doctoral Thesis). pp. 1–198. doi:10.3929/ethz-a-000611458. hdl:20.500.11850/140499.
  3. Pieroni, Vittorio; Nützel, Alexander (2014-11-30). "RASATOMARIA GENTILII GEN. N. SP. N. - A NEW MIDDLE TRIASSIC PLEUROTOMARIOID GASTROPOD GENUS AND SPECIES FROM RASA DI VARESE (SAN SALVATORE FORMATION, SOUTHERN ALPS)". Rivista Italiana di Paleontologia e Stratigrafia. 120 (3). doi:10.13130/2039-4942/6073. ISSN   2039-4942.
  4. Pieroni, Vittorio; Furrer, Heinz (2020-02-12). "Middle Triassic gastropods from the Besano Formation of Monte San Giorgio, Switzerland". Swiss Journal of Palaeontology . 139 (1): 2. Bibcode:2020SwJP..139....2P. doi: 10.1186/s13358-019-00201-8 . ISSN   1664-2384. S2CID   211089125.
  5. López-Arbarello, Adriana; Bürgin, Toni; Furrer, Heinz; Stockar, Rudolf (2016-07-19). "New holostean fishes (Actinopterygii: Neopterygii) from the Middle Triassic of the Monte San Giorgio (Canton Ticino, Switzerland)". PeerJ. 4: e2234. doi: 10.7717/peerj.2234 . ISSN   2167-8359. PMC   4957996 . PMID   27547543.