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Long-term dynamic topographic support during post-orogenic crustal thinning revealed by stable isotope (?¹⁸O) paleo-altimetry in eastern Pyrenees.

ABSTRACT: Understanding the geodynamic and Earth surface processes at the origin of post-collisional surface uplift in mountain ranges requires reconstruction of paleo-elevation. Here, we focus on the topographic evolution of the Cerdanya Basin in the eastern Pyrenees formed by post-orogenic extension during the Late Miocene. Stable isotope (?¹⁸O) analyses of small rodent teeth and biogenic carbonates show the basin uplifted by 500?m since 6.5?Ma. These new paleoaltitudes constraints when combined with the regional geology and geophysical data reveal the anomalously high topography of the region is the result of density changes in the sublithospheric mantle associated with crustal thinning and then opening of Gulf of Lion during the Chattian-early Burdigalian.

SUBMITTER: Huyghe D

PROVIDER: S-EPMC7010729 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Long-term dynamic topographic support during post-orogenic crustal thinning revealed by stable isotope (δ<sup>18</sup>O) paleo-altimetry in eastern Pyrenees.

Huyghe Damien D Mouthereau Frédéric F Ségalen Loïc L Furió Marc M

Scientific reports 20200210 1

Understanding the geodynamic and Earth surface processes at the origin of post-collisional surface uplift in mountain ranges requires reconstruction of paleo-elevation. Here, we focus on the topographic evolution of the Cerdanya Basin in the eastern Pyrenees formed by post-orogenic extension during the Late Miocene. Stable isotope (δ<sup>18</sup>O) analyses of small rodent teeth and biogenic carbonates show the basin uplifted by 500 m since 6.5 Ma. These new paleoaltitudes constraints when combi ...[more]

PMID: 32041988

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