Canjuers Lagerstätte

The Canjuers Lagerstätte is a Konservat-Lagerstätte located inside the military camp of Canjuers, in Haute Provence, in the Var department in South-East France.[1]

Canjuers Lagerstätte
Stratigraphic range:
Canjuers military camp : Bessons quarry, where the Compsognathus fossil was found.
TypeKonservat-Lagerstätte
Unit ofCalcaires blancs de Provence
UnderliesBiomicrites de Sainte-Croix
Thickness12 m
Lithology
PrimaryLithographic limestone
OtherChert
Location
Coordinates43.708695°N 6.374173°E / 43.708695; 6.374173
Region Provence-Alpes-Côte d'Azur
Country France
Type section
Named forCanjuers plateau
Canjuers Lagerstätte is located in France
Canjuers Lagerstätte
Canjuers Lagerstätte (France)

Geology and stratigraphy

From a stratigraphic point of view, this fossil deposit is located inside the Calcaires blancs de Provence geological formation, a 200-meter-thick limestone assemblage. The lithographic limestone of Canjuers, which bears almost all significant fossils from the Lagerstätte, is a thin layer (around 6 meters) at the basis of the Biomicrites de Sainte-Croix member, the later member of the Calcaires blancs de Provence.[2] This layer has been dated by ammonite analysis to the Lower Tithonian (Neochetoceras mucronatum biozone[3]), around 150 Mya.

The Canjuers site facies outcrop in the Petit Plan de Canjuers plateau, and a quarry was exploited in the locality "Les Bessons". They correspond to deposits inside a sub-circular depression whose area is estimated to be only 1 km2.[1] Their total thickness is around 12 m. They are divided in three lithologic units, from bottom to top :

  • The lithographic limestone per se, made of thin limestone, finely laminated, around 6 m thick. Those bears almost every remarkable fossils from the site (Lagerstätte).
  • Bioclastic limestone 4.5 m thick. Those are packstone or grainstone limestone, with chert nodule levels. Their bioclasts are made of corals, sea urchins, bivalves, brachiopods and sponges fragments, with burrows and some plant remains. The banks show quasi-planar oblique surface.
  • The sub-lithographic limestone with chert nodule levels, 1.5 m wide, in thick banks perforated by burrows attributed to the ichnotaxon Tubularina lithographica.[4]

Paleoenvironment

The lithographic limestone deposit environment was protected from the Tethys Ocean open sea by a continuous reef barrier. The lithographic limestone was deposited in a large lagoon whose various parts were successively above and below water, and where several small coral islands emerged. Meteoric water supplies are likely.[3]

Paleontology

Actinopterygians

Genus[1]SpeciesOrderFamilyImages
CaturusC. sp.AmiiformesCaturidae
EugnathusE. sp.AmiiformesCaturidae
GyrodusG. sp.PycnodontiformesGyrodontidae
ProscinetesP. sp.PycnodontiformesPycnodontidae
PachycormidaePachycormiformesPachycormidae
PholidophorusP. sp.PholidophoriformesPholidophoridae
LeptolepisL. sp.LeptolepiformesLeptolepidae
TharsisT. sp.LeptolepiformesLeptolepidae
OphiopsisO. sp.IonoscopiformesOphiopsidae
ElopidaeElopiformesElopidae
LepidotesL. sp.LepisosteiformesLepidotidae
BelonostomusB. sp.AspidorhynchiformesAspidorhynchidae
NaiathelonN. okkidionElopomorpha

Sarcopterygians

Genus[1]SpeciesOrderFamilyImages
UndinaU. sp.Actinistia
CoccodermaC. sp.Actinistia

Chondrichthyans

Genus[1]SpeciesOrderFamilyImages
PalaeocarchariasP. sp.Lamniformes

Reptiles

Genus[1]SpeciesOrderFamilyImages
SolnhofiaS. sp.CheloniaPlesiochelydae
EurysternumE. sp.CheloniaEurysternidae
PleurosaurusP. ginsburgiRhynchocephaliaPleurosauridae
P. goldfussiRhynchocephaliaPleurosauridae
HomoeosaurusH. maximilianiRhynchocephaliaSphenodontidae
LeptosaurusL. pulchellusRhynchocephaliaSphenodontidae
PiocormusP. laticepsRhynchocephaliaSphenodontidae
AeolodonA. priscusMesoeucrocodyliaTeleosauridae
CycnorhamphusC. suevicusPterosauriaGallodactylidae
CompsognathusC. longipesDinosauriaCompsognathidae

Echinoderms

Genus[1]SpeciesOrderFamilyImages
PlegiocidarisP. marginataEchinoideaCidaroida
RhabdocidarisR. nobilisEchinoideaCidaroida
DiplocidarisD. giganteaEchinoideaCidaroida
HemicidarisH. crenularisEchinoideaHemicidaroida
AcrocidarisA. nobilisEchinoideaHemicidaroida
HessotiaraH. florescensEchinoideaHemicidaroida
PseudosaleniaP. asperaEchinoideaSalenioida
PleurodiademaP. stutziEchinoideaPhymosomatoida
AcropeltisA. aequituberculataEchinoideaArbacioida
MagnosiaM. nodulosaEchinoideaArbacioida
PentasteriaP. sp.AsteroideaPaxillosida
GeocomaG. canjuersensisOphiuroideaOphiuridae
G. aff. carinataOphiuroideaOphiuridae
AmphiuridaeOphiuroideaAmphiuridae
OphiurellaO. aff. speciosaOphiuroideaincertae sedis
ComaturellaC. pinnataCrinoideaComatulida
SaccocomaS. tenellaCrinoideaRoveacrinida

Brachiopods

Genus[1]SpeciesOrderFamilyImages
TorquirhynchiaT. guebhardiRhynchonellida
SeptaliphoriaS. obtusaRhynchonellida
Somalirhynchia ?S. sp.Rhynchonellida
JuralinaJ. insignis' Terebratulida
MoeschiaM. aff. foraminataTerebratulida
IsmeniaI. pectunculoidesTerebratulida
"Zeilleria"Z. aff. pentagonalisTerebratulida

Molluscs

Genus[1]SpeciesOrderFamilyImages
ModiolusM. imbricatusBivalvia
EntoliumE. corneolumBivalvia
ChlamysC. textoriaBivalvia
SpondylopectenS. subpunctatusBivalvia
NanogyraN. striataBivalvia
ActinostreonA. gregareumBivalvia
DorsoplanitoidesD. triplicatusCephalopoda
UsselicerasU. (Subplanitoides) altegyratumCephalopoda
U. (Subplanitoides) aff. spindelenseCephalopoda
U. (Subplanitoides) cf. schwertschlageriCephalopoda
U. (Usseliceras) cf. franconicumCephalopoda
HibolitesH. sp.Cephalopoda

Crustaceans

GenusSpeciesOrderFamilyImages
CycleryonC. bourseaui[5]Decapoda
Kouphichnium[1]K. lithographicumChelicerataXiphosura

References

  1. Peyer, Karin; Charbonnie, Sylvain; Allain, Ronan; Läng, Emilie; Vacant, Renaud (2014). "A new look at the Late Jurassic Canjuers conservation Lagerstätte (Tithonian, Var, France)". Comptes Rendus Palevol. 13 (5): 403–420. doi:10.1016/j.crpv.2014.01.007.
  2. Atrops, F. (1991). "Le Tithonique en Provence à la lumière de la datation par ammonites du gisement de Canjuers (Var, France)". Comptes Rendus de l'Académie des Sciences, Série II. 313 (8): 909–915.
  3. Atrops, F. (1994). "Présence d'ammonites du Tithonien inférieur dans les Calcaires lithographiques de Canjuers (Var, France) ; conséquences stratigraphiques et paléogéographiques". Geobios Mem. Spec. 16: 137–146. doi:10.1016/S0016-6995(94)80028-6.
  4. Gaillard, C.; Bernier, P.; Gall, J.C.; Gruet, Y.; Barale, G.; Bourseau, J.P.; Buffetaut, E.; Wenz, S. (1994). "Ichnofabric from the Upper Jurassic lithographic limestone of Cerin, Southeast France". Palaeontology. 37 (2): 285–304.
  5. Audo, D.; Charbonnier, S.; Schweigert, G.; Saint Martin, J.-P. (2014). "New eryonid crustaceans from the Late Jurassic Lagerstätten of Cerin (France), Canjuers (France), Wattendorf (Germany) and Zandt (Germany)". Journal of Systematic Palaeontology. 12 (4): 459–479. doi:10.1080/14772019.2013.777809. S2CID 128805162.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.