La Matilde Formation

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La Matilde Formation
Stratigraphic range: Bathonian-Kimmeridgian
~167–151  Ma
Type Geological formation
Underlies San Julián Formation
Overlies Chon Aike Formation
Lithology
Primary Claystone, sandstone, siltstone
Other Coal beds, conglomerate, tuff
Location
Location Patagonia
Coordinates 47°36′S68°06′W / 47.6°S 68.1°W / -47.6; -68.1
Approximate paleocoordinates 44°12′S27°18′W / 44.2°S 27.3°W / -44.2; -27.3
Region Santa Cruz Province
CountryArgentina
Extent Austral Basin
Relief Map of Argentina.jpg
Cyan pog.svg
La Matilde Formation (Argentina)

La Matilde Formation is a Jurassic geological formation in the Austral Basin of Santa Cruz Province, Patagonia, Argentina. It is dated to the Middle to Late Jurassic. From the Bathonian age (164.7 to 167.7 million years ago) to the Kimmeridgian age (150.8 to 155.7 million years ago) at the latest. [1] [2] [3]

Contents

The area was once part of the subtropical and temperate regions of the southern supercontinent Gondwana in the Mesozoic era, a more or less continuous landmass consisting of what is now modern South America, Africa, Antarctica, Australia, New Zealand, and New Guinea. [4] [5]

Description

La Matilde consists primarily of sedimentary rocks. It includes claystone, coal beds, conglomerates, siltstones, sandstones, and volcanic tuff. La Matilde overlies but sometimes intersperses with the Middle Jurassic Chon Aike Formation. [6] The two formations are the subunits of the Bahía Laura Group. [1]

Fossil content

La Matilde is known for the abundant fossils recovered from it. Notable fossil localities in the formation include the Cerro Cuadrado Petrified Forest, the Cerro Madre e Hija Petrified Forest, and the remains and trace fossils (including trackways) of dinosaurs in the Laguna Manantiales Farm. [7] [8]

Fossil taxa recovered from the La Matilde Formation include: [9] [10]

Flora
Ichnofossils

See also

Related Research Articles

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References

  1. 1 2 Claudio A. Sylwan (2001). "Geology of the Golfo San Jorge Basin, Argentina" (PDF). Journal of Iberian Geology . 27: 123–157. ISSN   0378-102X.
  2. Channing et al., 2007
  3. Clarke et al., 2011
  4. Sequiera & Farrell, 2001
  5. Iglesias et al., 2011
  6. Ana Parras; Miguel Griffin (2009). "Darwin's great patagonian tertiary formation at the mouth of the río Santa Cruz: a reappraisal". Revista de la Asociación Geológica Argentina. 64 (1). ISSN   1851-8249.
  7. Fernando E. Novas (2009). The age of dinosaurs in South America. Indiana University Press. p. 99. ISBN   978-0-253-35289-7.
  8. IUCN Commission on National Parks and Protected Areas (1982). IUCN directory of neotropical protected areas. IUCN. pp.  26–27. ISBN   978-0-907567-62-2.
  9. Thomas N. Taylor; Edith L. Taylor; Michael Krings (2009). Paleobotany: the biology and evolution of fossil plants. Academic Press. p. 844845. ISBN   978-0-12-373972-8.
  10. Ruth A. Stockey; T.N. Taylor (1978). "On the structure and evolutionary relationships of the Cerro Cuadrado fossil conifer seedlings" (PDF). Botanical Journal of the Linnean Society. 76 (2): 161–176. doi:10.1111/j.1095-8339.1978.tb01504.x.
  11. Channing, A.; Zamuner, A.; Edwards, D.; Guido, D. (2011). "Equisetum thermale sp. nov. (Equisetales) from the Jurassic San Agustin hot spring deposit, Patagonia: Anatomy, paleoecology, and inferred paleoecophysiology". American Journal of Botany. 98 (4): 680–697. doi: 10.3732/ajb.1000211 . hdl: 11336/95234 . PMID   21613167.
  12. Leonardi, 1994, p.27
  13. 1 2 Leonardi, 1994, p.26
  14. Leonardi, 1994, p.25

Bibliography

Further reading