High-resolution 3D geomodel of the central Po-Plain, Northern Italy.

Abstract

The Po Plain in Northern Italy constitutes an elongated alluvial valley characterized by an intricate geological evolution, extending from the late Paleozoic era to recent times. Notably densely populated, this region accommodates approximately one-third of the Italian population and hosts critical industrial facilities, coupled with a substantial history of oil and gas exploration and production. Given these factors, the creation of a high-resolution subsurface geomodel is imperative for various applications in this region. Tectonically, the Po Plain is located in the Adria Microplate and is bounded by two opposite verging orogens sharing the same foreland: the Northern Apennines (NA) to the south, and the Southern Alps (SA) and the Western Alps to the north and the west. The SA are a south-verging fold-and-thrust belt, while the NA are a north-northeast-verging fold-and-thrust belt; both belts have their outer thrust front buried beneath the Neogene-Quaternary sediments of the Po Plain. The front of the Northern Apennines is structured into three different arcs with increasing amounts of shortening, from northwest to southeast: the Monferrato Arc, the Emilia Arc, and the Ferrara Arc. Along the Emilia Arc, the juxtaposition of the buried Southern Alps and the buried Northern Apennines is notably close, allowing for a more detailed analysis of their frontal convergence (a few kilometers). Moreover, the influence on the thrust(s) geometry from the inherited and inverted structural highs from the passive Mesozoic platform can be observed more clearly. This combination of factors, among others, makes the central area of the Po-Plain one of the most prolific for oil and gas production, hosting several productive fields.Despite the long story of hydrocarbon exploration and production, a large-scale comprehensive 3D model using seismic lines and well information has not yet been published, apart from a couple of very good seismic sections, that have been studied and analyzed multiple times. In particular, the Plio-Pleistocene architecture of the basin has been only partially described. In this study, we have used an extensive database provided by ENI Spa to create a high-definition static model and several balanced cross-sections to understand better the distribution of the deformation along the Emilia arc and to comprehend how the complex relationship between NA, SA, and the inherited structural highs have driven the actual architecture of the central Po-Plain subsurface. This new highly detailed 3D geomodel provides the necessary base to implement renewable energy developments (geothermic) in one of the most populated areas in Italy.