Background

Gravimetric monitoring detects changes in subsurface mass by measuring variations in the gravitational field. At volcanoes, these signals can indicate magma intrusion, withdrawal, or hydrothermal fluid movement.

At Poás, gravimeter data are used together with GNSS and gas observations to constrain processes in the hydrothermal system and shallow magmatic reservoir. Gravimetric observations provide an additional dimension to multiparametric monitoring by capturing mass changes not evident in surface deformation alone.