Magmatic eruption of White Island volcano, New Zealand, December 1976–April 1977

White Island volcano erupted fresh andesite during March 1977, in the first emission of new lava bombs and blocks recorded in historic time. Preliminary analytical data indicate that the new lava differs petrographically and chemically from all other analysed White Island lavas. The eruption commenced with ejection of accessory ash derived from crater floor debris, overlying a shallow magma intrusion which has been causing inflation of the crater floor since 1973.