RICONOSCIMENTO ED ANALISI DI ALCUNE ASSOCIAZIONI DI STRUTTURE SINSEDIMENTARIE PRE-OROGENICHE IN APPENNINO CENTRALE

Abstract

Crustal thinning processes affecting the Afro-Adiatic palaeomargi.n in pre-miocene times are recorded, at a regional scale, by the differentiation between complete and condensed sedimentary successions within the umbro-marchean sequence and by partial variations in the thickness of the Scaglia litho­types. Such variations are the result of a synsedimentary Cretaceus-Paleogene tectonic activity which is testified by the development of regional structures trending roughly N-S and E-W and by minor features characterized by more scattered orientations. The acquisition and the analysis of the mesos­tructural data presented in this study allowed usto derive use­fui indications about the stress field acting during the pre­orogenic extensional phases, as well on the role that pre­existing structures played during the compressional phases responsible for the present-day structural setting of the cen­trai Apennines.