Figure 5: Δg vs. Δh values numerically computed^31,53,54 for the inflation (ΔP = 18 MPa) of an ellipsoidal source at a depth of 3 km with a compressible magma χ = 0.2 GPa⁻¹ embedded in an elastic medium μ = 30 GPa.

Ellipsoidal sources at constant volume (equivalent to a sphere with radius of 1 km) and with different aspect ratios e between the major and minor axes ranging from 0.2 to 2 (prolate ellipsoid e > 1; sphere e = 1; oblate ellipsoid e < 1) are considered (see Methods). The Δg and Δh values for an aspect ratio of about 1.6 is in general agreement with the data (red dots) observed during the 1997 recharging phase (Fig. 3c, box I).