Person:
Pieren Pidal, Agustín Pedro

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First Name
Agustín Pedro
Last Name
Pieren Pidal
URI
https://hdl.handle.net/20.500.14352/75218
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Geodinámica, Estratigrafía y Paleontología
Area
Estratigrafía
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UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

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Start date: 2000 × Subject: 551.7 ×

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    Asociaciones palinológicas del tránsito Rhaetiense-Hettangiense en Asturias (España)
    (Geotemas, 2005) Barrón López, Eduardo; Gómez Fernández, Juan José; Goy Goy, Antonio; Pieren Pidal, Agustín Pedro
    The palynological study of 49 successive samples collected from the Vilorteo and Cantavieyo Diamond Drill Holes, drilled in the La Camocha Mine area, near Gijón (Asturias), allowed the characterization of three palynological assemblages. The oldest assemblage (PA 1) is characteristic of the Rhaetian. A precise age for the middle assemblage (PA2) cannot be assigned, due to the scarce productivity of the samples. The youngest assemblage (PA3) is characteristic of the Hettangian. Consequently the Triassic-Jurassic boundary (TJB) is located within the upper part of the carbonate succession of the Solís Mb. Two pa/ynozones, Rhaetipollis germanicus one and Krausselisporites reissingeri Zone, have been established. Their boundary nearly coincides with the TJB. A quantitative analysis reveals an increase in the proportion of hygrophilous and warmer taxa near the TJB, compatible with a global climatic change probably related with the end-Triassic mass extinction.
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    A ~565 Ma old glaciation in the Ediacaran of peri‑Gondwanan West Africa
    (International Journal of Earth Sciences, 2018) Pieren Pidal, Agustín Pedro; Linneman, Ulf; Hofmann, Mandy; Drost, Kerstin; Quesada Ochoa, Cecilio; Gerdes, Axel; Marko, Linda; Gärtner, Andreas; Zieger, Johannes; Ulrich, Jens; Krause, Rita; Vickers-Rich, Patricia; Horak, Jana
    In the Cadomian orogen of the NE Bohemian Massif and of SW Iberia, a post-Gaskiers glacial event dated at c. 565 Ma has been detected. Such Ediacaran-aged glaciomarine deposits occur in the Weesenstein and Clanzschwitz groups of the Saxo-Thuringian zone (Bohemia) and in the Lower Alcudian group of the southern Central Iberian zone (Iberia). Both areas are parts of Cadomia situated in the Western and Central European Variscides. Glaciomarine sedimentary rocks are characterized by such features as dropstones, flat iron-shaped pebbles (“Bügeleisen-Geschiebe”), facetted pebbles, dreikanters, and zircon grains affected by ice abrasion. For age and provenance determination, LA–ICP–MS U–Pb ages (n = 1124) and Hf isotope (n = 446) analyses were performed. The maximum age of the glaciomarine deposits within a Cadomian back-arc basin based on U–Pb analytics resulted in the youngest detrital zircon populations showing ages of 562–565 Ma and of c. 566–576 Ma old zircon derived from granitoid pebbles within the diamictites. The youngest age recorded was 538–540 Ma based on zircon from the plutons which had intruded the previously deformed Ediacaran metasedimentary rocks. Previously described glaciomarine diamictites of Cadomia (Weesenstein, Clanzschwitz, and Orellana diamictites) are most definitely younger than the c. 579–581 Ma Gaskiers glaciation in Newfoundland (Gaskiers) and in SE New England (Squantum). We propose the term Weesenstein–Orellana glaciation for this new Ediacaran glacial event, named after the most relevant regions of exposure. Palaeogeographically, these glaciomarine diamictites and related sedimentary deposits lie on the periphery of the West African Craton (western peri-Gondwana), and evidence has been provided by detrital zircon U–Pb ages and their Hf isotope composition. Correlation with similar glaciomarine deposits in the Anti-Atlas (Bou Azzer) and Saudi Arabia suggests a continued distribution of post-Gaskiers glacial deposits along the Gondwana margin of Northern Africa. The Weesenstein–Orellana glaciation correlates in part with the Shuram–Wonoka δ13C anomaly.
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    Public dissemination of knowledge regarding Ordovician geologicaland palaeontological heritage inprotected natural areas of Iberia
    (Acta palaeontologica sinica, 2007) Gutiérrez Marco, Juan Carlos; Rábano, Isabel; Sá, Artur A.; San José, M.Á. de; Pieren Pidal, Agustín Pedro; Sarmiento Chiesa, Graciela Noemí; Piçarra, José Manuel; Durán, Juan J.; Baeza, Eleuterio; Lorenzo Álvarez, Saturnino