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Geological structure and relief of the Caucasus. Caucasus is built with 4 orogenic elements and the modern theories looked him like the alpin-geosynclinal, orogenetic model. The new geophysical researches about the origin of the Black and Caspian Sees are showing that the Caucasian space results from the clamping by two continental slabes.

Glaciers and climate in the Western and Central Caucasus. After an abstract about the Caucasus climate, the authors show a statistical distribution of the glaciers, the genesis of the avalanches and a typology of the avalanchous regions. They show that the glaciers are climatological indicators, found the feeding-ablation balances and their annual changes during the last 10 years.

With 6 350 species, the Caucasian flora and the Caucasian fauna are among the richest of the middle latitudes. Plenty of the vegetable and animal species are endemic. The arctico-alpine constituents are rare. The high mountain flora and fauna are enriched, during the Quaternary, with interior-asiatic components, wrongly called « alpine ». Their part, in the ecosystems is, of course, greater to east.

Caucasus is remaining a woodland in spite of felling to extend pasturages and cultivated grounds. However, the deforestation made necessary protection measures notably against the avalanches and the erosions. Man has above all rendered scarse or made to disappear the authochtonous fauna. Preservation measures had been taken from before the October Revolution and especially during the sovietic regime. Caucasus has to day 28 preserves from 3 to 2 850 km2. The author describes the Caucasus natural Park and the Teberda natural Park.

The geomorphological comparative analysis in the Western French Alps and in the Caucasian mountainous systems shows the structural and orogenical differences, the amplitude of recent raising, the considerable place of the seismicity and volcanism in the Caucasus; the glaciological expansion to the Western Alpine piedmonts while the Caucasian glaciers do not go out the mountain.

General and specific features of glaciological regimes and their oscillations in the Western Alps and in the Caucasus. The both climate mountains are chiefly different by continental degree. The thermic secular change is marked by a continual cooling down in the high Caucasus, while Caucasian piedmonts, plains and mountains of the Western Europe were becoming warmer up to 1955-60. The Caucasus glaciers fronts are lower than the one A Ipine glaciers. They have a more diversified typology. The values of the ice-mass changes are rather similar. The both mountains have temperate glaciers (soaked with water) and cold glaciers (higher than 3 000 m in the Alps and 3.500 m in the Caucasus).

Alps-Caucasus, a comparative bio-geography. The Caucasian flora and fauna are richer in species and more diversified than the ones of the Alps, because of the climatological Caucasian situation; the existence, during the Quaternary, of refuges (Lands without ice) and the less human activity.

Alps-Caucasus. Chief resemblances and differences in the vegetable covers. In the both mountains, plenty of commun features in the vegetable kingdom are attesting a same origin. The Caucasus has a richer flora. The differences between the species and the high endemism are resulting from the old and marked mountain-isolations.

The historical stages in the settlement and economic development are clearly distinct. The Alps are very linked together with the adjacent plains while the feudal regime longly remained in the Caucasus. That is the reason why the economic activities are more intense in the Alps, specially touring, on account of the proximity of the European big towns and metropolis. On the contrary, the naturel defence is earlier and more efficient in the Caucasus.