Studio Sedimentologico e Stratigrafico di un sondaggio nell’Istmo di S. Antioco (Sardegna sud-occidentale)

Sedimentological and stratigraphical study of a drilling in the Isthmus of St. Antioco (South-Western Sardinia)

Abstract

The drilling has cut across a continental sterile formation attributed to Plio-Pleistocene. We verified that the isthmus is situated in a narrow graben deepening to Tirreniano included and we think that the deepening is actual, in consequence of a partially submerged Roman road. We analyzed 17 samples from drilling in order to determine their textural characteristics and to extract some information about the environment of sedimentation. The sediments are the result of mixing two populations in various proportions: a dominant medium sandy fraction and a subordinate silty fraction. Skewness and kurtosis reflect this mixing: size distribution curves are positive-skewed, leptokurtic and also poorly sorted. We correlated then these characteristics with those of modern dune, beach and river sands, results suggest that analyzed sediments have undergone a fluvial transport and sedimentation in deltaic environment.