A pilot project of anthropogenic Venice uplift by deep seawater injection
M. Ferronato, G. Gambolati, M. Putti, P. Teatini
Dept. Mathematical Methods and Models for Scientific
Applications, University of Padova, Padova, Italy
G. Brancolini
Department of Geophysics of the Litosphere, OGS, Trieste, Italy
P. Campostrini
Co.Ri.La., Venezia,
Italy
ABSTRACT
Recent modeling studies suggest that injecting seawater into a 600-800 m deep
salty aquifer underlying the Venice Lagoon might help raise the city uniformly
by 25-30 cm, and possibly up to 40 cm, over a 10 year time. To test the
feasibility of an actual programme of anthropogenic Venice uplift a pilot
project is designed with the aim at investigating the expected occurrence over
a limited area selected on purpose within the lagoon where three boreholes down
to 800 m are drilled, and seawater properly treated for geochemical
compatibility is continuously injected into the geologic formation of interest
during 3 years. Using an improved reconstruction of the geologic formations
based on new seismic surveys to be carried out in the lagoon area, the pilot
project plans the continuous monitoring and accurate measurement of:
1- fluid pore pressure, 2- expansion of the injected underground units,
3- vertical and horizontal motions of the overlying land surface via spirit
levelling, GPS and InSAR. A continuous real-time control of the experiment is
envisaged with the aid of site specific much refined hydrologic and
geomechanical models properly calibrated over the detailed litho-stratigraphy
resulting from the new seismic analyses, ad hoc field tests and the most
recently available hydrological and geomechanical data of the Northern
Adriatic basin. The present communication addresses a few basic issues
concerned with the design of the pilot project and discusses the results
expected form the experiment.
