Anisotropies of anhysteretic remanence and magnetic susceptibility of marly clays from Central Italy

Abstract

Marly clays from an Upper Pliocene unit at Valle Ricca (Rorne) were investigated for their Anisotropy of Anhysteretic Remanence (AAR) and Anisotropy of Magnetic Susceptibility (AMS). The study of AAR was accomplished for the first time in ltaly, developing a suitable laboratory technique and adapting a standard statistical procedure. The comparison between anhysteretic remanence and magnetic susceptibility anisotropies discriminates the fabric of the ferromagnetic fraction from that of the paramagnetic matrix of the rock. The separation of fabric components was applied to distinguish subsequent geological processes that affected the total rock fabric. The results indicate that the clayey units are particularly suitable for the empirical investigation of fabric to strain relationship in weakly deformed rocks.