ETEROPIE DI FACIES NEL TRIAS SUPERIORE E NEL LIAS INFERIORE DEL GRAN SASSO

Abstract

Three stratigraphic sections are briefely described in ord­er to show the variation of facies from W to E along the Gran Sasso ridge during the late Triassic - early Jurassic: a) Valle dell'Inferno - Corno Grande section (shallow water carbonate platform) with Dolomia Principale fm. and Calcare Massic­cio fm.; b) Canala - M. Prena section (transition, probably a ramp) with basinal bituminous dolomites (Dolomie Bituminose) in the lower part and shallow water dolomite (Dolomie del M. Prena) in the upper part; c) Canale di Vradda - M. Tremoggia section that represents an euxinic to normally oxigenated basin with bituminous dolomites (Dolomie Bituminose) in the lower part and cherty dolomites (Dolomie di Vradda), burrowed spotted limestones (Calcari Maculati) and cherty limestone (Strati Ammonitici di Vradda, Cornio­la fm.) in the upper part.