|
|
"A tout Seigneur, tout honneur"
 It is the star and we will begin this review
by it. Emblematic mountain
of Auvergne, it gave are name at the department administration.
The Giant of the Domes, of the Romans,
while passing through Pascal,
to the the famous bicycle champion couple Anquetil-Poulidor,
is really a star. Moreover, it is seen by far: its altitude raised
compared to the surrounding plates in fact a mythical mountain.
By walk, to horse, to vapor, to bicycle, to car, français anglais
arabe And soon, thanks to the cogwheel train, named Panoramique
des Dômes, it gives desire for climbing it. And, it
is true that it is attracting, because to its node, it offers
an exceptional point of view.
|
 |
|
The
top view of Puy de Dôme show a west dome which was surely
perfect
| |
A 10 000 years " young fellow "
It is its age. It is little, compared to the first
buildings of the Chain (100 000ans). Before its formation, the few habitants of
the Clermont plain (which did not exist), observed in the place a modest
Strombolian slag cone. Not what to put an aerial. The Western profile
of the Clermont horizon was of course extremely different. Its construction
is complex, and the facts history difficult to know. It is in an initial Strombolian
cone that is born, then builds a first dome
of a very viscous lava which
no flow, but remains at the vertical of the emission mouth. The development
did not known major incident and altitude
approaches an exceptional values for this
type of dynamism. During this phase of the volcanic ash clouds to the limited
extent, cover the neighbourhoods calcining the surrounding forests. The dome is
almost perfect, comparable with the dome of the "Soufrière' in Guadelup. The
building could remained in the state, but a few time after an
explosion breaks the East part.Then another
dome takes the place while rising in the ploughed up part. A progression
identical to the first, but more pointed which will give this characteristic form
than one sees today. The most destroying phase is during this explosion. The model
of comparison is the peeled Mountain in Martinique which knew apparently the same
scenario (with for consequence destruction of the town of Saint Pierre). The
neighbours " is powdered " on the one, of the deposits
of the volcanic clouds emitted during the formation, and on the other,
fragments of the East part. The vegetation will cover the area gradually, until
side events occur later on like the explosion of the Kilian
crater, 8500 years ago, and which marks the end (provisional?) of volcanic
episodes of the Puy de Dôme. | |
3D map 
Puy de Dôme
remains the highest volcano of the Chain of Puys
with its 1465 Mr. His rise was done since the Romaine time by the path
of the Muleteers on his South-western face. In 1907, a tram with vapor
made it possible Clermontois to climb without effort the giant of the Domes. The
current road uses its layout which makes 1 turn 1/4 around the building with a
regular slope of 12%. We can reach in the car, or the bus for the estival period.
This solution, initiated by the General council, limits circulation during the
moments of strong frequentation, and goes in the direction of the
safeguarding of the environment. The pedestrian rise by the path
of the muleteers is nevertheless a pleasant moment. On the basis of the "Col de
Ceyssat", the path rises on uneven of 400 m, making discover a vast panorama on
the Southern volcanos and the Massif du Sancy. The climbing time is about 2h to
4h according to the rate/rhythm which one asserts. By looking at the 3D card
with a pair of glasses with relief (filter
right eye: blue; filter left eye: red), you will have an original sight of Puy
de Dôme. If you do not have any, manufacture in one with transparent paper
with the colors indicated, or buy it  .Thus
equipped, aim the screen directly at 0,50 m of distance (or print the map). |
| |
| Nature
of the lava Puy de Dôme
did not produce lava flows (except the clouds artdentes and the blocks projected
during the explosion of the East side). The emitted products are trachytes,
very viscous lava, which while cooling, induces a white
and friable rock. The lava of this type is called "Dômite".
The paste of the rock comprises phenocrysts (large crystals) of black biotite
(mica) and quartz. The silica content (SiO2) is one of highest (65%), by making
an acid lava. | | |
Science and Puy de Dôme September 19 the 1648 node was
the theatre experiment of Blaise Pascal, who,
using the barométre of Torriceli, highlighted the variation
of atmospheric pressure according to altitude. It is his brother-in-law,
Mr. Perrier, who carried out the operation. The history tells that Pascal have
never climbed the Puy de Dôme by fear to be asphyxiated. It is for that
that it had entrusted work to his brother-in-law. |
 Atmospheric
pressure according to altitude | | |
|
