When NZGS personnel visited the island on 14 April, they observed few differences in 1978 Crater. The small green ponds present during the previous visit on 22 March had enlarged and merged to cover 60-70% of the crater floor. Color ranged from orange adjacent to the fumaroles to lime green. Fumarolic activity continued on the W wall and up the NW-trending gully system. Activity at Donald Mound appeared to have declined, but no fumarole temperatures were measured. Very small changes in tilt were recorded: +8 mm about 150 m W of Donald Mound, and +9 mm about 100 m N of it. The NZGS noted that these changes indicated an end to the deflation of the Donald Mound area recorded between November 1982 and January 1983 (figure 8).

Geological Summary. The uninhabited Whakaari/White Island is the 2 x 2.4 km emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The island consists of two overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater is open at sea level, with the recent activity centered about 1 km from the shore close to the rear crater wall. Volckner Rocks, sea stacks that are remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826 have included intermittent moderate phreatic, phreatomagmatic, and Strombolian eruptions; activity there also forms a prominent part of Maori legends. The formation of many new vents during the 19th and 20th centuries caused rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project. Explosive activity in December 2019 took place while tourists were present, resulting in many fatalities. The official government name Whakaari/White Island is a combination of the full Maori name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island (referencing the constant steam plume) given by Captain James Cook in 1769.

Information Contacts: P. Otway, NZGS, Waikarei; B. Scott, NZGS, Rotorua; G. Sorrell, DSIR, Wellington.