GEOLOGIA DEI MONTI SIBILLINI NORD-ORIENTALI

Abstract

In this paper the authors illustrate the geology of the north-eastern part of the Sibillini Mountains (Ap­pennino umbro-marchigiano), on the basis of a geologi­ca! survey (in the scale 1:25.000) extending from the upperValleyof the Fiastrone River (to the North) to the Tenna Valley (to the South). The outcropping units are those typical of the um­bro-marchigiana facies. Some of them, however (calcari a Posidonia, calcari diasprini umbro-marchiginai, scaglia rosata, schlier) present special peculiarities in their litho­logy in relation to the abundant supply of calcareous­detrital materials. The provenance of these carbonatic materials is external to the umbro-marchiginao basin. In particular the turbiditic deposits of calcari e marne del Sentina can replace the rosso ammonitico (Toarcian-Aa­lenian) and younger layers of the corniola (Upper Pliensbachian). [...]