Radiocarbon dating pedogenic carbonates

Due to the complex tectonics of the Corbières, strongly influenced by the Pyrenean orogeny, the Jurassic-Cretaceous limestones do not comprise a continuous aquifer.

The depth of karstification, several hundred metres below sea level, especially in the Opoul area and in Lower Agly, is mainly linked to: (i) the Messinian salinity crisis, when the base level fell of 1500 m, and (ii) to the infiltration of meteoric waters with a strong dissolution power controlled by weather conditions (Dörfliger et al, 2008b).

Therefore, various examples of the Th dating of carbonate cements were provided through conglomerates of the proglacial valley fills of Austria (Ostermann et al., 2006), the alluvium terraces in New York State (Seleck and Baran, 2003), pedogenic layers (Rubin and Sieh, 1997; Vincent et al., 2007), calcretes in the soils (Geyh and Eitel, 1998; Srivastava, 2001), tufaceous carbonates (Haynes et al The Verdouble River is the main tributary of the Agly River, which it joins on his left bank downstream to Estagel (fig. It flows through a subalpine valley located in the Corbières hilly area.

The bedrock is Silurian and Devonian in the north of the catchment, Jurassic for uplands bounding the catchment in the south and finally Jurassic and Cretaceous for the downstream course of the Verdouble and the Vingrau-Tautavel plain.

Implications paléoenvironnementales relatives au site paléolithique de Tautavel (Pyrénées-Orientales) The Pleistocene alluvial conglomerates of the Verdouble River valley, close to the famous Palaeolithic site of Tautavel, were the object of lithologic determinations including microtextural analysis intended to define their provenance, their sedimentary facies and their calcite cement.

The cements are thought to have developed during very early diagenesis allowing the consolidation and the preservation of the deposit.

Fifteen new AMS dates from these cements will lead us to propose a Late Pleistocene geomorphic and processes history for the Verdouble Valley, and for the Tautavel region, that is slightly different from that of a widespread assumption that Verdouble alluvium are mid-Pleistocene or older ages (Berger et al., 1997).

Previous age assignments by other authors envisage that these conglomerates belong to the MIS 7 (Mindel-Riss interglacial).

For the first time, single-phase and some polyphase cements were AMS 48,000 years BP.

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