Structural evolution of the Lucanian Apennines, southern Italy

In this paper we present a study of an entire segment of the Southern Apennines of Italy, extending from the Pollino mountain range to the south, to the Agri Valley to the north, in which ail the units of the chain are represented. Combining regional information with detailed structural data obtained from the different tectonic units forming the orogenic belt, the structure as well as the tectonic evolution of this portion of the orogenic belt are proposed. The overall architecture of this segment of the Southern Apennines mountain chain represents the result of a complete orogenic cycle in which oceanic subduction, syn-collisional and post-collisional events are well recorded. Structurally, this segment of the orogenic belt exhibits two distinct structural levels, separated by a major detachment surface (the sole thrust of the Accretionary wedge), that occur at the surface in the allochthonous nappes and at depth in the Adria continental margin. The upper level is characterized by an imbricated fan system affecting the allochthonous terranes emplaced during oceanic subduction and the first stages of continent-continent collision. The lower level is represented by a duplex geometry that has developed in the post-collisional stage, during evolution of the foreland migrating thrust system, involving the carbonate platform-basin system of the Adria block. During the last stages of the mountain building process, when the foreland thrust migration was locked by the thickening of the colliding continental crusts, the Southern Apennines were thus affected by a severe strike-slip tectonics that dissects the entire mountain belt deeply modifying the previous thrust geometry. (C) 1998 Elsevier Science Ltd. All rights reserved.