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pile-up had been pushed bodi-
ly fifty, sixty and even seventy
kilometres over its neighbour.
Erosion subsequently exposed
the different layers. The top of
the Matterhorn is a fragment of
Africa!

But why did the African conti-
nent move? North America
and Greenland had begun
to drift away from Northern
Europe creating the embryo-
nic Atlantic Ocean. Millions
of years later, the great land
mass lying in the southern
hemisphere -- Gondwanaland
-- began to break up. South
America, Australia, Antarctica
and India began to split away
from Africa. India ultimately
crashed into the bottom of Asia
to form the Himalayas. Thus re-
leased from this burden, Africa
began to drift inexorably nor-
thward, narrowing the former
ocean and crushing everything
that lay in its path. As this plate
pushed northward with irre-
sistible force, the shape of the
landscape changed many times. Finally, about 25 million years see today, peaks must have rea-
The ocean became a shallow sea, ago, there was no where to go but ched 10,000 even 12,000 metres—
islands appeared, the sea was cut off, upward and the young Alps began erosion has carried most of it away.
dried out leaving salt beds, was re- to emerge. The powerful process
placed by fresh-water lakes, but the continued unabated until an ex- It should not be imagined that the
sea broke through again—this cycle traordinarily high mountain range collision of continents took place
repeated itself over and over again. was formed. On the basis of what we any faster than it is happening to-
day—a few millimetres
per year. But we do
know that at one stage
the uplift was extre-
mely intense—layers of
rock tipped up at such
steep angles that they
collapsed into multiple
folds under the effect of
gravity and deep beds
of broken rock, gravel,
sand and mud washed
down by torrents from
vast heights. Under
Lausanne there are 4.5
kilometres of sediment.
In short, the geology of
the Alps is total chaos.
The granite core of
Mont Blanc that may
have once lain twenty-
five kilometres under-
ground lies exposed
nearly five kilometres
above sea level.

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