The regular monitoring of radioactive marker positions along a vertical borehole can provide in-situ measurements of deep rock compaction. Developed in the ‘70s, in recent years the effectiveness of this technology has been often debated. The present communication analyses the state of the art of the radioactive marker technique and provides a critical review on the role that these measurements might play in the future evolution of land subsidence monitoring and modelling.

The effects of land subsidence could be devastating on heavily settled coastal plains. In a scenario of sea-level rise, high costs are expected to protect coastal cities and touristic hotspots and to keep drained reclaimed lands. In this work, we calculated subsidence rates (SR) in the Po coastal plain, over the last 5.6 and 120 thousand years, providing information about land movements before human intervention became the main driver of subsidence, through water and gas withdrawal.

The Venice coastland forms the major low-lying area in Italy and encompasses a variety of environments, such as farmlands, estuaries, deltas, lagoons and urbanized areas. Since most of the territory lies at a ground elevation below or slightly above the mean sea-level, also a few mm/yr of land subsidence can seriously impacts on the coastal system. In this study, we present an analysis of the vulnerability to relative sea-level rise (RSLR) considering an uneven land subsidence distribution.

The numerical prediction of land subsidence above producing reservoirs can be affected by a number of uncertainties due to several factors. In this work, we use a Bayesian approach to reduce the initial uncertainties about the mechanical parameters in order to improve the reliability of land subsidence predictions. The numerical results obtained in an experiment on a real-world gas field confirms that is a valuable and effective approach.

This work reports results of experiments made in analogue materials reproducing the occurrence and propagation of fractures associated with land subsidence driven by groundwater pumping. We compare the physical experimental model results with a numerical model that tests the development of stresses above a bedrock ridge that forms the base of an aquifer.

We have depicted the continental and marine surficial water–groundwater interactions in a large portion of the coastland encompassing the southern Venice lagoon and the northern Po river delta. The saltwater-fresh water transition zone is very irregularly-shaped and mainly depends on the morphologic setting and the subsoil architecture. An over-consolidated Pleistocene clay layer and buried Holocene sandy paleo-channels and paleo-ridge systems controlled the saltwater-fresh water exchanges.

We investigate the effects of digging a navigable canal on the hydrogeological system underlying a coastal lagoon. The research has been promoted by the Venice Water Authority, which is investigating different possibilities to avoid the passage of large cruise ships through the historic center of Venice, Italy. Numerical simulations supported by a proper hydrogeological characterization show that the exchange of water and contaminants from the subsurface and surface systems will be significant.

Within the framework of the EU project IMPROWARE, our goal was to investigate a Mediterranean coastal aquifer in Egypt and develop scenarios for artificial aquifer remediation and recharge. The results of an extensive hydrogeophysical investigation were successfully used as an input in regional and local hydrological models to understand the hydrological evolution of the area. The research outcomes clearly highlight the effectiveness of using advanced geophysical and modeling methodologies.

We developed a method to characterize the distribution and variance of the hydraulic conductivity k in a multiple-zone alluvial fan by fusing multiple-source data. Consistently with the scales of the sedimentary transport energy, the k variance of the various facies decreases from the upper to the lower portion along the flow direction. The 3-D distribution of k is consistent with that of the facies. The potentialities of the proposed approach are tested on the Chaobai River megafan, China.

The stress variation induced by overdraft of aquifers in sedimentary basins may cause ground rupture in the form of activation of pre-existing faults or earth fissure generation. The process is severely threatening many areas in China and Mexico. Ruptures yield discontinuity in the displacement and stress fields that classic finite element (FE) models cannot address. We proved how Lagrangian approach provides more stable solutions than Penalty approach.

Eighty regular TerraSAR-X acquisitions over the 2008-2011 period significantly improve the subsidence monitoring at the Venice coastland. Settlements of 30-35 mm/yr have been detected at the three lagoon inlets in correspondence of the MoSE works. The Venice and Chioggia historical centers show local sinking bowls up to 10 mm/yr connected with the construction of new large buildings or restoration works. In the city of Venice, the mean subsidence of 1.1±1.0 mm/yr confirms its general stability.