Sand Liquefaction Phenomena During the Seismic Crisis of May 2012 in Emilia, Northern Italy

中文摘要: In May 2012, the Emilia region of the Po Valley was struck by a seismic crisis with two major events of magnitude M w 6.1 and M w 5.9. The first event induced widespread sand blows formed along buried channels and old crevasse splay deposits. In the days immediately following the events, the detailed mapping and sampling of the erupted sand was fundamental to record all the seismically-induced phenomena. The study of a trench dug across large fractures at San Carlo (Ferrara) provided also valuable information on the sand blows mechanism and regome. The sedimentological and compositional characteristics of the fracture-filling materials indicate that the sands were erupted from a layer located between 6.8 and 7.5 m depth. Older and deeper Holocene and Pleistocene sand layers were not apparently involved in the liquefaction phenomena.
Abstract:In May 2012, the Emilia region of the Po Valley was struck by a seismic crisis with two major events of magnitude M w 6.1 and M w 5.9. The first event induced widespread sand blows formed along buried channels and old crevasse splay deposits. In the days immediately following the events, the detailed mapping and sampling of the erupted sand was fundamental to record all the seismically-induced phenomena. The study of a trench dug across large fractures at San Carlo (Ferrara) provided also valuable information on the sand blows mechanism and regome. The sedimentological and compositional characteristics of the fracture-filling materials indicate that the sands were erupted from a layer located between 6.8 and 7.5 m depth. Older and deeper Holocene and Pleistocene sand layers were not apparently involved in the liquefaction phenomena.