Geography and geology refer to the southern part of the Eastern Alps as the Southern Alps . They move from Lake Lugano (north of Milan) 200 km east and north-east via Trentino-South Tyrol (Italy) to East Tyrol (Austria) and South Carinthia . From there they run southeast to Friuli and Slovenia , where the transition to the Dinarides is fluid.
The boundary between the southern and central Alps is the Periadriatic Seam , which is marked by wide long valleys . Because there are also crystalline masses south of the long valley furrow, the Alpine Club division of the Eastern Alps speaks of the Southern Eastern Alps and the Western Eastern Alps . A large part of the Southern Eastern Alps - and also the Southern Alps - is taken up by the Southern Limestone Alps : On the surface, the Southern Alps consist largely of carbonates ( limestone and dolomite ). Geologic-tectonically which forms a large part of the Eastern Alps constituent Eastern Alps part of Dinarian ceiling system .
The southwest section of the actually in more southerly latitudes lying western Alps (France, northern Italy) refers to the geography as Maritime Alps , they relate to the Southern Alps mentioned herein in any geological context.
Geologically , the Alps are structured into four large tectonic units : Penninic and Helvetic , Eastern and Southern Alps . The southern Alps are the mountain ranges south of the Periadriatic line ( Centovalli ( Melezzatal ) - Veltlin ( Addatal ) - Tonale pass - Pustertal - Gailtal - Karawanken ).
In contrast to the (geologically understood) Eastern Alps, the Southern Alps face south Vergent, that is, the alpine overthrusts and folds face south, while those of the Eastern Alps face north (northern Vergent). The southern Alps are thrust over the geologically young strata on the southern edge of the Alps on several fault lines , and there are thrusts in their interior that involve them; but one can hardly speak of a ceiling structure as in the northern building units. The effects of the southern Alpine rim tectonics include: a. the Friulian earthquake of 1976 .
Essentially, the Southern Alps are tectonically less complex than the Eastern Alps. In the Southern Alps there are, in addition to the generous Mesozoic formations, significant Paleozoic deposits ( Carnic Alps , Southern Karawanken, Variscan nappes). In the subsurface of the northern edge of the Southern Alps (periadriatic seam), it was previously assumed that the root zone of the Northern Limestone Alps had disappeared , since all structural units north of the periadriatic seam appear to be steeper as they approach it and seem to disappear underground. Today we know that the construction of the Alps is much more complicated and that, firstly, the steep position goes back to a bulging of the Alpine vault in late folding phases, and secondly, the periadriatic seam in its current form only after the thrust of the Northern Limestone Alps and the Overlaying the individual ceilings became effective.
In terms of physical geography , the Eastern Alps are subdivided into the longitudinal valley furrows in the Northern Alps , Central Alps and Southern Alps . The term then corresponds to the petrological rock zone of the Southern Limestone Alps without strict delimitation to limestone, regardless of the various local rock deposits, such as volcanic nature, as well as the southern pre-Alps .
Under climatic and cultural criteria of regional geography , the term Southern Alps includes roughly the same regions as that of physical geography, but refers to the Bacher Mountains , which actually form the foothills of the Central Alps, in the east, as well as the Ortler Alps , the Sobretta-Gavia- Group and the Bergamasque Alps to Lake Como , so it includes the Alpine region south of the Adda - Etsch - Eisack - Drau line .
- R. Oberhauser, FK Bauer: The geological structure of Austria . Springer, 1980, ISBN 3-211-81556-2 , pp. 92–115 ( main chapter from page 92 f. In the Google book search).
- Reinhard Schönenberg, Joachim Neugebauer: Introduction to the geology of Europe . 4th edition. Verlag Rombach, Freiburg 1981, ISBN 3-7930-0914-9 , p. 185 ff .