Assessment of liquefaction potential in the central Po plain from integrated geomorphological, stratigraphic and geotechnical analysis

Abstract

Large portions of the highly populated central Po Plain in northern Italy are susceptible to major liquefaction–induced ground failure and resulting damage, as illustrated by the 2012 Mw 5.6–5.8 earthquake sequence. Our work presents a comprehensive geomorphological, stratigraphic and geotechnical dataset from a 1012 km2 study area in the alluvial plain, analysed through the integration of different methodologies. For hazard reduction planning, we qualitatively and quantitatively assess liquefaction potential by the identification of three discrete geomorphological domains. Each geomorphological domain has variable Late Pleistocene to Holocene geological evolution, geotechnical characteristics and thus liquefaction susceptibility, as deduced from interpretation of three 25–m deep continuous cores and calculation of liquefaction potential based on the geotechnical analysis of 239 cone penetration tests (CPTs). For land use planning, we present this information at various map scales consistent with inherent uncertainties of data availability. The investigation procedures and geological–geotechnical interpretations may be applicable to similar liquefaction–prone areas elsewhere.