Between 1995 – 2000, interferograms show a deformation signal near Iliamna, much of which seems to have occurred during 1996–1997 when a seismic swarm was recorded at the volcano. This seismic swarm has been attributed to a possible dike intrusion. Modelling the InSAR observations for a  rectangular dike source yields a best-fit model that is a NW–SE-striking subvertical dike 7 9 8 km in dimension and centered at ~8 km depth. After this time interferograms show no evidence of deformation.