Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina

During the Middle Oxfordian, the epicontinental shelf of the Neuquén Basin was a site of major coralline evolution and reef building. This work expounds the studies performed on the La Manga patch reefs at Portada Covunco locality, near Zapala city, Neuquén province. Based on the results of 12 facie...

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Detalles Bibliográficos
Publicado: 2017
Materias:
Argentina
Coral reefs
Facies/microfacies
La Manga Formation
Middle Oxfordian
Neuquén Basin
Paleoenvironments
carbonate platform
coral reef
environmental change
facies
Gondwana
morphotype
Oxfordian
paleoenvironment
Neuquen Basin
Anthozoa
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01729179_v63_n1_p_Beresi
http://hdl.handle.net/20.500.12110/paper_01729179_v63_n1_p_Beresi
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_01729179_v63_n1_p_Beresi
record_format dspace
spelling paper:paper_01729179_v63_n1_p_Beresi2023-06-08T15:18:47Z Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina Argentina Coral reefs Facies/microfacies La Manga Formation Middle Oxfordian Neuquén Basin Paleoenvironments carbonate platform coral reef environmental change facies Gondwana morphotype Oxfordian paleoenvironment Argentina Neuquen Basin Anthozoa During the Middle Oxfordian, the epicontinental shelf of the Neuquén Basin was a site of major coralline evolution and reef building. This work expounds the studies performed on the La Manga patch reefs at Portada Covunco locality, near Zapala city, Neuquén province. Based on the results of 12 facies/microfacies types and the vertical succession of coral morphotypes a shallowing-upward trend ranging from a shallow subtidal-lagoon- to intertidal settings is inferred. The microfacies model suggests an ooidal shoal area in the highest energy zone and various patch reefs on the shallow carbonate platform. Autochthonous reefal facies comprise a low diversity of platy coral and mixed coral-siliceous sponge framestone, ramose coral bafflestone, and microbial bindstone. Non-reefal facies are composed of ooidal packstone, bedded bioclastic wackestone-packstone, and marl levels. Several shallowing-upward episodes are evidenced by local erosional surfaces (main exposure surface-MES). The succession of platy corals (exclusively Australoseris) followed by ramose corals (Etallonasteria, Stelidioseris, and Stephanastrea rollieri) probably reflects local environmental changes. The upward change in reefal composition is best interpreted in response to extrinsic physical parameters (local relatively minor sea-level fluctuations). Siliceous sponges occur in low percentages. The La Manga reefal succession could be correlated with the “global carbonate reef event”. This event occurred in most basins associated with the Tethyan oceanic belt and the North Atlantic Ocean, in low paleolatitude. The Portada Covunco reefs grew at higher paleolatitudes (nearly 39° south), within an embayment of the Neuquén Basin, with open circulation to the paleo-Pacific Ocean on the southwestern margin of the Gondwana realm. © 2016, Springer-Verlag Berlin Heidelberg. 2017 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01729179_v63_n1_p_Beresi http://hdl.handle.net/20.500.12110/paper_01729179_v63_n1_p_Beresi
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Argentina
Coral reefs
Facies/microfacies
La Manga Formation
Middle Oxfordian
Neuquén Basin
Paleoenvironments
carbonate platform
coral reef
environmental change
facies
Gondwana
morphotype
Oxfordian
paleoenvironment
Argentina
Neuquen Basin
Anthozoa
spellingShingle Argentina
Coral reefs
Facies/microfacies
La Manga Formation
Middle Oxfordian
Neuquén Basin
Paleoenvironments
carbonate platform
coral reef
environmental change
facies
Gondwana
morphotype
Oxfordian
paleoenvironment
Argentina
Neuquen Basin
Anthozoa
Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
topic_facet Argentina
Coral reefs
Facies/microfacies
La Manga Formation
Middle Oxfordian
Neuquén Basin
Paleoenvironments
carbonate platform
coral reef
environmental change
facies
Gondwana
morphotype
Oxfordian
paleoenvironment
Argentina
Neuquen Basin
Anthozoa
description During the Middle Oxfordian, the epicontinental shelf of the Neuquén Basin was a site of major coralline evolution and reef building. This work expounds the studies performed on the La Manga patch reefs at Portada Covunco locality, near Zapala city, Neuquén province. Based on the results of 12 facies/microfacies types and the vertical succession of coral morphotypes a shallowing-upward trend ranging from a shallow subtidal-lagoon- to intertidal settings is inferred. The microfacies model suggests an ooidal shoal area in the highest energy zone and various patch reefs on the shallow carbonate platform. Autochthonous reefal facies comprise a low diversity of platy coral and mixed coral-siliceous sponge framestone, ramose coral bafflestone, and microbial bindstone. Non-reefal facies are composed of ooidal packstone, bedded bioclastic wackestone-packstone, and marl levels. Several shallowing-upward episodes are evidenced by local erosional surfaces (main exposure surface-MES). The succession of platy corals (exclusively Australoseris) followed by ramose corals (Etallonasteria, Stelidioseris, and Stephanastrea rollieri) probably reflects local environmental changes. The upward change in reefal composition is best interpreted in response to extrinsic physical parameters (local relatively minor sea-level fluctuations). Siliceous sponges occur in low percentages. The La Manga reefal succession could be correlated with the “global carbonate reef event”. This event occurred in most basins associated with the Tethyan oceanic belt and the North Atlantic Ocean, in low paleolatitude. The Portada Covunco reefs grew at higher paleolatitudes (nearly 39° south), within an embayment of the Neuquén Basin, with open circulation to the paleo-Pacific Ocean on the southwestern margin of the Gondwana realm. © 2016, Springer-Verlag Berlin Heidelberg.
title Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
title_short Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
title_full Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
title_fullStr Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
title_full_unstemmed Coral patch reef system and associated facies from southwestern Gondwana: paleoenvironmental evolution of the Oxfordian shallow-marine carbonate platform at Portada Covunco, Neuquén Basin, Argentina
title_sort coral patch reef system and associated facies from southwestern gondwana: paleoenvironmental evolution of the oxfordian shallow-marine carbonate platform at portada covunco, neuquén basin, argentina
publishDate 2017
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01729179_v63_n1_p_Beresi
http://hdl.handle.net/20.500.12110/paper_01729179_v63_n1_p_Beresi
_version_ 1768542408671232000

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