Mineralization in geosynclines — the Alpine enigma

Abstract

The problem of the paucity of post-Hercynian mineralization in the Alps compared with the rich mineral endowment of other young fold mountain belts of the same world wide system has for long been an unsolved puzzle. It is suggested that the key to this problem can be found in relating the Alpine geosyncline to the plate tectonic framework within which it evolved. Hsu's suggestion that the Alpine geosyncline did not develop at a convergent juncture, but occupied part of the region where the African and European plates were moving laterally past each other leads on to the inference that subduction of oceanic crust did not take place on any significant scale during the evolution of the geosyncline or its subsequent deformation. This accounts for the relative absence of porphyry copper deposits and Cyprus-type massive sulphide deposits. Consideration of the possible history of the Alpine geosyncline in the light of plate tectonic theory accounts not only for the absence of these oretypes but also provides an explanation for the presence of some of the few major metalliferous deposits of this orogen. This in turn suggests the consideration of certain genetic models for the origin of these deposits and has important overtones with regard to mineral exploration in the Alps.