Quantification of volcanic explosions from tilt records: Volcلn de Colima, México

During the 2004–2005 explosive sequence at Volcán de Colima, México, impulses with a duration of several minutes were recorded by a two-component tiltmeter installed at a distance of 1.6 km from the crater for 46 Vulcanian explosions. The correlation between the amplitudes of tilt impulses A = √(Arad2 + Atang2) and the energy of explosions E estimated from the broadband seismic records is significant at the 99% confidence level. The regression equation can be used to estimate the energy of explosions at Volcán de Colima from the tilt records.