151ment for this volcano (Table 8.3 ). The RenDateModel also
enabled us to assess that the interval between the eruptions of
Montcineyre and Pavin was about 100–700 years in duration
at the 95 % confi dence level.
The present data collection of the available chronological
information on the MEMP group shows the potential for
improvement. The poor precision of half of the measured
ages is also shown by the large width of the distribution
curves (Fig. 8.6 ). In fact, the age corpus is still very weak for
the three companion volcanoes of the Pavin, whereas the
region offers various possibilities to fi nd, in palaeosols prin-
cipally, charred vegetable remains which could be dated by
means of A.M.S.; it was not the case at the time of the publi-
cation of the majority of the dates available today.
8.5 Was Pavin Eruption the Latest
Eruption in the Chaîne des Puys?
The literature refers to possible volcanic activity in the
Chaîne des Puys after the Pavin eruption. At four localities,
sandy beds are present in stratigraphic positions postdating
the Pavin eruption.
N.B. For pollen features cited below, see above the sketch
pollen diagram of Fig. 8.2.
Camus ( 1975 ) pointed out the presence of a sandy layer
interbedded in swamp deposits of the Etang de Fung in the
Sioule valley. Underlying non-charred wood remains were
dated at 3890 ± 110 B.P. (GIF-2349), which is a maximum
age for the sandy layer and which places it in the protohis-
toric period.
Juvigné et al. ( 1986 ) described a millimeter-thick sandy
layer in the pure peat body of the Maar of Beaunit. The layer
is composed of a large variety of minerals so that the mate-
rial cannot be linked with any eruptives of previously inves-
tigated volcanoes. A peat segment containing the sandy bed
was dated at 5020 ± 120 B.P. Nevertheless, in the relevant
pollen sequence the bed is situated at the 2 %-point of the
continuous curve of Fagus (mean date in the Massif Central:
4994 ± 47 B.P. after Juvigné et al. 1988a ) and much deeper
than the Neolithic regression of the pollen trees (Juvigné
et al. 1986 : p. 34, Fig. 2; see above Fig. 8.2 ). The provisional
name of Beaunit tephra was applied to the sandy layer while
waiting for further identical fi ndings elsewhere.
Juvigné et al. ( 1988b ) described two cm-thick sandy beds
at depth 6.5 m in the 13.5 m thick pure peat body of the Narse
d’ Espinasse (Juvigné et al. 1986 : p. 12, Fig. 3; see above Fig.
8.2 ). Mineralogical composition and texture were different
from each other. Both layers, and the lowest depletion of pol-
len trees corresponding to the Neolithic epoch in the pollen
diagram, are synchronous. Since these layers are not present
in the nearby peat bog of the Narse d’ Ampoix , their origin is
attributed to the accelerated erosion due to drastic Neolithic
deforestation. The distribution area of the sandy beds has not
been verifi ed. The site, being off a delta front, indicates that
scattered lenses can be expected in the peat.
Fourmont et al. ( 2006 ) found in the Marais de Sarlièvre
(Grande Limagne plain, near Clermont-Ferrand) a thin sandyFig. 8.5 Crater Pavin:
smoothed probability
distributions for the calibrated
ages (years B.C.) for
individual^14 C measurements
and resulting distribution
( lower diagram ), based on the
assumption that the 5 age
results concern a unique
event, the Pavin eruption
(Program RenDateModel,
Lanos et Dufresne 2012 ).
Data from Table 8.1
Table 8.3 Results of the compilation of the age data given in Table xxx, in years, obtained by means of the program RenDateModel (Lanos et
Dufresne 2012 ) along with the calibration data from IntCal2009 (Hughen et al. 2009 )
Volcano B.C. interval B.C. median age Present age (in 2014) +/−
Pavin 4880–4560 4720 6730 170
Montchal 5190–4640 4920 6930 270
Estivadoux 5310–4730 5020 7030 290
Montcineyre 5410–4830 5120 7130 290
The quoted age is the median one, given as B.C. (column # 3) and as present age (column # 4; “present age” = B.C. age + 2010). Uncertainties are
given at the 95 % confi dence level. Stratigraphic constraints reminded in the text were accounted for in the computing process
8 Distribution, Tephro- and Chronostratigraphy of the Widespread Products of Pavin Volcano