Geophysical data acquisition - OGS

Transferring technology from the oil and gas industry to environmental
application is a goal we pursued within the MICA Project, funded by the “Fondo
Trieste”. We acquired a high-resolution 3D survey close to the Trieste airport, in an
area where the city aqueduct has several catchment wells. The tomographic
inversion and imaging of this data showed not only a good correlation with the
available stratigraphy from 3 wells, but also remarked the significant vertical and
lateral variations of the layers overlying the water-saturated formations. This fact
proves the viability of 3D surveys for the protection of groundwater from pollution,
and also their need: sparse 2D profiles would miss the area complexity;
furthermore, drilling sparse exploration wells would be not only even less
significant (and probably more expensive), but could break the impermeable
covers over the groundwater pool, allowing it to be polluted by industrial or
agricultural activities.
Complementary to the seismic surveys, we carried out also a Georadar and a geoelectric
survey, for integrating the elastic and electro-magnetic parameters. Of
course, the penetration scale of the different techniques is quite different (but
complementary), and their integration into a consistent physical model is
ongoing. Partner of OGS within the MICA Project is GeoKarst, which is a
geochemical company located in the Trieste Area Science Park. This company is
complementing the OGS activity by analyzing the water origin and fluxes by
measuring the isotopes it contains.
The stratigraphy
of 3 water well (above)
matches the pre-stack
depth migrated section
(below) obtained by
tomographic velocities
in a high-resolution
3D survey.
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