Oxfordian sponge association from the Neuquén basin, Mendoza, West-central Argentina.

BERESI MATILDE S.

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Oxford, UK; Año: 2003 vol. 16 p. 105 - 112

0895-9811

PERGAMON Journal of South American Earth Sciences 16 (2003) 105-112 Journal of South American Earth Sciences 16 (2003) 105-112 www.elsevier.comllocateljsames www.elsevier.comllocateljsames Oxfordian sponge association from the Neuquen basin, Mendoza,     west central Argentina Oxfordian sponge association from the Neuquen basin, Mendoza,     west central Argentina Matilde Sylvia Beresi* Cricyt-lanigla. A. RIl;: Leal sin. Parque Gral. San Martin. 5500 Mendo:za. Argentina Received I May 2001: accepted 1 July 2001 This  paper describes an Upper Jurassic association of siliceous sponges from the Neuquen basin, southern Mendoza province, at Rio Malal. Wackestones crop out in this stratigraphic section, and massive sponge-bearing micritic limestones of the La Manga formation (Plicatilis  zone) have been deposited in outer shelf to slope settings. Sponges are regularly preserved as whole bodies. Their skeletons are mostly calcified, but the skeletal siliceous structure is sometime preserved. The siliceous sponges belong to the Order Hexactinosa (Class  Hexactinellida, Subclass Hexasterophora) (Laocoetis sp. L paralela,  L. proumbens,  Cribrospongia sp., C. clathrata, C. cucullata, Ordinatus sp., Linonema calyx) and Lyssakinosa (Poligoniatum sphaeroides). The majority of the sponge specimens correspond to the families Cribrospongiidae (genus Cribrospongia) and Laocoetidae (genus Laocoetis). The Upper Jurassic carbonates are interpreted as deposits  of a highstand systems tract, similar to other Oxfordian sequences found around the world.   13 Elsevier Ltd. All rights reserved. ,´Ortis: Oxfordian sponge: Mendoza province: Neuquen basin ´3 Elsevier Ltd. All rights reserved.