Triangular Facets or Flatirons? A note of caution from the Lucanian Apennines, Italy

In this contribution we present the preliminary re- sults of a structural analysis carried out in Val d’Agri, a seismically active domain located in the heart of the southern part of peninsular Italy. Here a Triassic-Tertiary pelagic sequence belonging to the Lagonegro Units was folded during the orogenic events that led to the construc- tion of the Southern Apennines fold-and-thrust belt. This folded sequence was then dissected by post-orogenic nor- mal faults. The results of a detailed field survey carried out along well-exposed triangular landforms make it pos- sible to unequivocally interpret these as flatirons, and hence to ascribe them to the folding process. This infe- rence appears significant, since the investigated lanforms, long known in the local geological literature, have been interpreted by many Authors as triangular facets related to a postulated active normal fault. Our findings indicate that caution is needed in the interpretation of triangular landforms in areas where folds and normal faults coexist.