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the Ariege valley, glaciers extended 62 km to an altitude of c. 300-400 m asl (Herail
et al. , 1986; Delmas et al ., 2011).
Several studies from lake and bog sequences within former glacier limits on both
the northern and southern slopes of the Pyrenees have produced radiocarbon ages
suggesting maximum glacier advances that were asynchronous with the record of
global ice volume - in several areas preceding the global LGM by tens of thousands
of years (e.g. Mardones and Jalut, 1983; Vilaplana, 1983; Andrieu et al. , 1988; Jalut
et al. , 1988; 1992; Montserrat 1992; Reille and Andrieu, 1995; Garcıa Ruiz et al. ,
2003; Gonzalez-Samperiz et al. , 2006). However, some authors have questioned
this interpretation, such as Turner and Hannon (1988, p. 57), who suggested that the
old 14 C ages, first reported in Mardones and Jalut (1983), are likely to have been
affected by hard-water error or possibly a mixture of reworked organic matter -
a view that was later reiterated by Pallas et al. (2007) who applied cosmogenic
nuclides to date glacial landforms.
Initially research suggested that cosmogenic nuclide analyses appeared to con-
flict with the dating frameworks that argue for an 'early' glacier maximum in the
Pyrenees and suggest a local glacier maximum after 25 000 years ago and close
in time to the global LGM at c. 21 ka. Pallas et al. (2007) presented 25 10 Be ex-
posure analyses for granodioritic glacial erosion surfaces and boulders in the Up-
per Noguera Ribagor¸ana Valley in the south-central Pyrenees. On the lowermost
glacial units, the oldest exposure age was 21
4.4 ka and was obtained from an
erratic boulder. Similar findings were reported by Delmas et al. (2008) from the
Carlit massif in the eastern Pyrenees. However, more recent data by these re-
searchers has revealed evidence for an earlier glacial maximum during the last
glacial cycle (Pallas et al. , 2010; Delmas et al. , 2011) and the initial contradic-
tions between radiocarbon and cosmogenic ages appear to have been the result of
insufficient data from comparable sites.
There is growing evidence for an 'early' glacier maximum in the Pyrenees. In the
Cinca and Gallego River valleys (south-central Pyrenees and Ebro Basin, Spain),
Lewis et al. (2009) interpreted optically stimulated luminescence (OSL) ages ob-
tained from glacial deposits and loess as indicating glacial periods at 85 ± 5 ka,
64
±
3 ka. They found that maximum extent of glaciers
during the last glacial occurred at 64 ± 11 ka and this provides independent support
for dating frameworks from other glacial sequences in the Pyrenees.
±
11 ka, 36
±
3 ka and 20
±
3.2.4 Maritime Alps
The Maritime Alps in southeast France and northwest Italy represent the southern-
most extension of the European Alps. They are situated only 50 km from the coast at
Monaco and are strongly influenced by Mediterranean climate systems. The high-
est peak is Argentera (3297 m asl) and this mountain supported some small glaciers
as recently as the twentieth century (see Section 3.3 on modern glaciers, below).
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