Title:
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Palaeoenvironments of the Late Miocene Prüedo Basin: implications for the uplift of the Central Pyrenees
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Author:
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Ortuño, M.; Martí i Castells, Anna; Martín-Closas, Carles; Jiménez-Moreno, G.; Martinetto, E.; Santanach i Prat, Pere F., 1946-
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Other authors:
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Universitat de Barcelona |
Abstract:
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The nature, structure and extent of a palaeo-basin sedimentary infill exposed in the Aran valley (Central Pyrenees) was studied by combining stratigraphical and biostratigraphical analyses and an audio-magnetotelluric survey. The basin developed on top of a pre-existing peneplain and was formed by the North Maladeta Fault activity. The fluvio-palustrine sequence filling the basin was at least 100 m thick. Specimens of the taxon Hippuris cf. parvicarpa Nikitin were identified for the first time in a European palaeoflora. The palynological and carpological analyses allowed us to (1) constrain the age of the basin infill as Vallesian (11.1-8.7 Ma), (2) characterize the vegetation of the belt surrounding the basin as a mainly temperate to warm-temperate assemblage, and (3) estimate the palaeoaltitude of the site at between 700 and 1000 m, which leads to an altitude change of 900-1200 m for the North Maladeta Fault downthrown block and 1640-1640 m for the upthrown block. These data allowed us to estimate the regional uplift of the area at between 0.08 and 0.19 mm a−1. The different exhumation values obtained by other researchers for sites located at both sides of the North Maladeta Fault are in agreement with its activity as a normal fault since the Late Miocene. |
Subject(s):
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-Paleoclimatologia -Miocè -Pirineus -Paleoclimatology -Miocene -Pyrenees |
Rights:
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(c) The Geological Society, 2013
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Document type:
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Article Article - Accepted version |
Published by:
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The Geological Society
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