Berriasian–early Valanginian calcareous shallow-water facies from the Arperos Basin: A proposal from the foraminiferal assemblage of the clasts of the Guanajuato Conglomerate, central Mexico
The Eocene Guanajuato Conglomerate is composed of clasts derived from igneous and metasedimentary sourc es that can be related to the Upper Jurassic–Lower Cretaceous arc and back-arc assemblages of the El Paxtle and Arperos Basin. Limestone clasts contain a shallow-water platform fauna that includes...
| Authors: | , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2015 |
| Country: | México |
| Institution: | Universidad Nacional Autónoma de México |
| Repository: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:94339885004 |
| Online Access: | https://www.redalyc.org/articulo.oa?id=94339885004 |
| Access Level: | Open access |
| Keyword: | Ciencias de la Tierra Berriasian early Valanginian Guanajuato Conglomerate Tethysian benthic foraminifera |
| Summary: | The Eocene Guanajuato Conglomerate is composed of clasts derived from igneous and metasedimentary sourc es that can be related to the Upper Jurassic–Lower Cretaceous arc and back-arc assemblages of the El Paxtle and Arperos Basin. Limestone clasts contain a shallow-water platform fauna that includes bivalves, brachiopods, gastropods, echinoderms and foraminifers. F oraminiferal studies were carried out on these limestone clasts. The benthic foraminiferal association is c omposed of Pseudocyclammina lituus (Yokoyama, 1890); Everticyclammina virguliana (Koechlin, 1942); Montsalevia salevensis (Charollais, Brönnimann and Zaninetti, 1987); Neo - trocholina valdensis (Reichel, 1955); Andersolina cherchiae (Arnaud-Vanneau, Boisseau and Darsac, 1988); Neotrocholina molesta (Gorbatchik, 1959); Pfenderina neocomiensis (Pfender, 1938); Nautiloculina bronnimanni Arnaud-Vanneau and Peybernès, 1978; Hechtina praeantiqua Bartenstein and Brand, 1949; Protopeneroplis cf. P. banatica Bucur, 1993; Istriloculina sp., Moesiloculina sp., Protomarsonella sp., Ammovertellina sp. and Glomospira sp. The Tethysian foraminiferal assemblage observed in the limestone clasts indicate the age of the calcareous source as Berriasian– early Valanginian, which is the age of the deposition within the Arperos Basin. The occurrence of these shallow-water limestone clasts suggests the existence of a shal low-water platform deposit located in the Arperos Basin. This is signiicant considering that all previous work focused on the deep-water sedimentary rocks (siliciclastic and calcareous). Thus, these clasts are a key to reconstructing the depositional history and architec ture of this basin. |
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