RAPID DEFORMATION OF THE SOUTH FLANK OF KILAUEA VOLCANO, HAWAII

The south flank of Kilauea Volcano has experienced two large [magnitud e (M) 7.2 and M 6.1] earthquakes in the past two decades. Global Posit ioning System measurements conducted between 1990 and 1993 reveal seaw ard displacements of Kilauea's central south frank at rates of up to a bout 10 centimeters per year. In contrast, the northern side of the vo lcano and the distal ends of the south flank did not displace signific antly. The observations can be explained by slip on a low-angle fault beneath the south flank combined with dilation deep within Kilauea's r ift system, both at rates of at least 15 centimeters per year.