:''See also the French département of
Puy-de-Dôme and several French places named
Le Puy''.
'Puy' is a
geological term used locally in the
Auvergne,
France for a
volcanic hill (the word deriving from the
Provencal "Puech", meaning an isolated hill). Most of the puys of central France are small
cinder cones, with or without associated
lava, whilst others are domes of
trachytic rock, like the domite of the
Puy-de-Dôme. The puys may be scattered as isolated hills, or, as is more usual, clustered together, sometimes in lines. The chain of puys in central France probably became extinct in late prehistoric time.
Other volcanic hills more or less like those of Auvergne are also known to geologists as puys; examples may be found in the
Eifel and in the small cones on the
Bay of Naples, whilst the relics of puys denuded by erosion are numerous in the
Swabian Alps of
Württemberg, as pointed out by
W. Branco. Sir
A. Geikie has shown that the puy type of eruption was common in the British area in
Carboniferous and
Permian times, as abundantly attested in central
Scotland by remains of the old volcanoes, now generally reduced by
denudation to the mere neck, or volcanic vent, filled with
tuff and
agglomerate, or plugged with lava.
See Sir A. Geikie, ''Ancient Volcanoes of Great Britain'' (1897).
References
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