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IVES 9 IVES Conference Series 9 Results of late-wurmian to present-day climatic-geological evolution on to spatial variability of pedologic-geological characters of the AOC Gaillac terroirs (Tarn, Midi-Pyrénées)

Results of late-wurmian to present-day climatic-geological evolution on to spatial variability of pedologic-geological characters of the AOC Gaillac terroirs (Tarn, Midi-Pyrénées)

Abstract

The AOC Gaillac area is divided into three main terroirs : « The left bank terraces », « The right bank coteaux » and « The plateau Cordais ». This division is valid at a regional scale, but it suffers of a number of local-scale exceptions. This spatial variability of the pedologic-geologic characteristics at the plot scale has been derived mainly from the main late-Würmian solifluxion phase occurring at the transition between the peri-glacial climate and the Holocene temperate conditions (13,000-10,000 yrs BP). This soil movement processing has generated tongue-shaped features composed of a mixed molassic-fluviatil material mostly on north-oriented slopes, concealing the in-situ molassic bedrock. This spatial variability has to be taken into account in any viticultural zoning strategy using extraction of morphometric data from a Digital Elevation Model (DEM) as slope gradient and slope orientation maps.

DOI:

Publication date: December 22, 2021

Issue: Terroir 2006

Type: Article

Authors

Pierre COURJAULT-RADE (1), Marguerite MUNOZ (1), Eric MAIRE1 et Nicolas HIRISSOU (2)

(1) Laboratoire des Mécanismes de Transferts en Géologie (LMTG), UMR 5563 CNRS, 14, avenue E. Belin, 31400 Toulouse, France
(2) Domaine du Moulin, chemin de Bastié, 81600 Gaillac, France

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Keywords

Gaillac, geology, scale analysis, terroirs, viticultural zoning

Tags

IVES Conference Series | Terroir 2006

Citation

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