Le microfacies del Calcare Massiccio (Giurassico inferiore, Gola di Frasassi, Appennino settentrionale) ed il loro colore.

The main purpose of this work is to confirm the possible correlation extant between the color of rock and microfacies in the stratigraphic section of Calcare Massiccio located into Cava Gola della Rossa (Serra San Quirico, Ancona). During the sampling field, 17 samples were collected. 17 thin sections were made and 5 of these samples were analyzed with and . The correlation between color and microfacies and a possible correlation between color and the content of limonitizated pyrite were established by petrographic analysis. Chemical analyses instead only suggest a correlation between color and content of Aluminum. The results of chemical analyses were inconclusive probably due to the small amount of samples. In the end, the presence of limonitized pyrite only in supratidal facies was related to the occurrence of stromatolites. At the same time, the higher content of silica minerals, suggested by high , in the supratidal strata was traced back to their deposition in a principally subaerial environment.