ATTI E MEMORIE DELLA COMMISSIONE GROTTE EUGENIO BOEGAN
Abstract
In this study we focus on the “Grotta Impossibile” cave, near Basovizza (Trieste). It was
discovered in November 2004 thanks to a highway tunnel construction. We report the results of
the gravimetric survey made over the part of the cave free of tree vegetation and demonstrate
that the gravity minimum over the cave is well defi ned. Additionally, we ran simulations of
the anomaly based on the available reliefs of the cave provided by speleological explorations.
The good agreement of the data with simulations disproves the existence of any branch yet to
discover of size comparable to the main hall of the cave, at least in the studied area. Furthermore,
we detect a gravimetric gradient equal to 0.00184·10−5 m/s2 per meter with a northward
positive change, which is due to subsurface density and structure inhomogeneities.
