Enciso Group

Last updated
Enciso Group
Stratigraphic range: Hauterivian-early Aptian
~135–118  Ma
Icnitas en Enciso.JPG
Ichnofossils near Enciso
Type Geologic group
Sub-units Leza & Jubela Formations
Underlies Oliván Group
Overlies Urbión Group
Lithology
Primary Sandstone, limestone
Other Marl, mudstone
Location
Coordinates 42°06′N2°18′W / 42.1°N 2.3°W / 42.1; -2.3
Approximate paleocoordinates 31°42′N9°00′E / 31.7°N 9.0°E / 31.7; 9.0
Region La Rioja
Country Spain
Extent Cameros Basin
Type section
Named for Enciso, La Rioja
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Green pog.svg
Enciso Group (Spain)
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Green pog.svg
Enciso Group (La Rioja, Spain)

The Enciso Group is a geological formation in La Rioja, Spain whose strata date back to the Early Cretaceous. [1]

Contents

The turtle Camerochelys was described from the Enciso Group. Dinosaur remains, including the holotype of the spinosaurid Riojavenatrix , are among the fossils that have been recovered from the formation.

The first spinosaurid fossil remains found at Igea, Enciso Group were a jaw fragment found in 1983 and isolated teeth.

Description

The Cameros Basin containing the Enciso Group represents continental synrift deposition. It consists of carbonate and siliciclastic lacustrine deposits. Cobble to boulder-sized dropstones and sand to silt sized IRD were observed in three different lithofacies. These are restricted glaciolacustrine shales, laminated glaciolacustrine silts, and proglacial sandy lobes correlated to glacier front retreat. This deep glacial lake system is compared favourably lacustrine sediment sequences related to Pleistocene glacial cycles of the Laurentide Ice Sheet in the eastern Canadian Arctic. This along with other evidence of cryospheric activity suggested extensive continental ice sheets during the Hauterivian Cold Snap. [2]

Fossil content

The following fossils have been found in the formation: [3]

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs

Theropods

Theropods of the Enciso Group
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Riojavenatrix [4] R. lacustrisA baryonychine spinosaurid
Riojavenatrix lacustris.png

Turtles

Turtles of the Enciso Group
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Camerochelys [5] C. vilanovaiA xinjiangchelyid turtle

See also

References

  1. Enciso Group at Fossilworks.org
  2. Rodríguez-López, Juan Pedro; Liesa, Carlos L.; Luzón, Aránzazu; Muñoz, Arsenio; Mayayo, María J.; Murton, Julian B.; Soria, Ana R. (2023-10-10). "Ice-rafted dropstones at midlatitudes in the Cretaceous of continental Iberia" . Geology. 52 (1): 33–38. doi:10.1130/G51725.1. ISSN   0091-7613.
  3. Weishampel et al., 2004, pp. 556-563
  4. Isasmendi, E.; Cuesta, E.; Díaz-Martínez, I.; Julio Company; Sáez-Benito, P.; Viera, L. I.; Torices, A.; Pereda-Suberbiola, Xabier (2024). "Increasing the theropod record of Europe: a new basal spinosaurid from the Enciso Group of the Cameros Basin (La Rioja, Spain). Evolutionary implications and palaeobiodiversity" . Zoological Journal of the Linnean Society. 202 (3): zlad193. doi:10.1093/zoolinnean/zlad193.
  5. A. Pérez-García; F.-R. Sáez-Benito; X. Murelaga (2017). "New information on the anatomy and systematics of the Spanish Lower Cretaceous Camerochelys vilanovai (Testudines, Pan-Cryptodira)". Journal of Iberian Geology. 43 (2): 147–154. doi:10.1007/s41513-017-0014-6. S2CID   133741760.

Bibliography

Further reading

Dinosaur footprints Yacimiento de Valdecevillo Enciso.jpg