James Healy was born at Devonport, Auckland, on 10 September 1910, the son of Sarah Roulston Wallace and her husband, William Healy, a marine engineer. He began his schooling at Devonport, and then took the ferry across the harbour to Mount Albert Grammar School. His first job was as a draughtsman in the Department of Lands and Survey, and in his spare time he studied geology at Auckland University College. He graduated BSc in 1933 and was working on his MSc thesis when a position became available in the Geological Survey Branch of the DSIR in Wellington. He transferred there in December 1934, initially as assistant geologist. He completed his MSc in 1935 and was promoted to geologist in 1937.
Healy was initially involved in the Geological Survey’s core work of mapping important mineral areas. He spent much time in the Waikaia mining area in Southland, where he met Mabel Gertrude Asher, daughter of the storekeeper at Balfour. They married there on 21 April 1939 and settled in Wellington, where the first of their three children was born.
During the war Healy checked deposits of various strategic minerals, and also advised on where to drill for water to supply new military camps, ‘with conspicuous success’, as his director reported. In a post-war reorganisation he was appointed to head a new office of the Geological Survey at Rotorua. On his arrival in October 1945 there were immediate problems to deal with concerning the exploitation of hot springs and a volcanic eruption at Ruapehu.
The Pacific Science Congress held in Auckland and Christchurch in 1949 gave Healy his first taste of international science. There were particularly stimulating discussions on volcanology after Ngauruhoe erupted spectacularly just as the visiting scientists arrived. However, a more pressing problem arose in the geothermal area. An urgent need for more power generation in the North Island had raised the question of whether geothermal steam could be used. By late 1949 the power shortage was so severe that the government decided that drilling for steam should start immediately without waiting for full scientific investigations.
Healy, with his proven skill at guiding the drillers, played a key role. He had already advised the government’s tourist department on drilling a bore for steam to heat its hotel at Wairakei, with such impressive results that this locality was chosen for the geothermal power project. He drew up the initial plan for a line of bores aimed at obtaining steam as well as information on the underlying geological structure. Again his recommendations proved sound, and development of a geothermal power station at Wairakei went ahead.
Although he was only peripherally involved in the continuing geological investigations of the Wairakei geothermal field, Healy was kept busy monitoring further eruptions at Ngauruhoe and investigating the lahar from Ruapehu which caused the Tangiwai rail disaster in 1953. He subsequently ranged widely over many other aspects of local geology, but his most important work continued to be in the geothermal and volcanological fields. He developed ideas on the mode of volcanism in the Taupo volcanic zone, recognising ‘cauldron’ structures from past volcanic activity, and from the 1960s he was part of the New Zealand programme of assistance to geothermal projects in many countries.
Jim Healy was eclectic in his interests, becoming involved with many activities beyond science, especially in music. He initially found Rotorua a very quiet town but took the initiative in forming a music appreciation group and then the Rotorua Chamber Music Society. For many years he wrote reviews of records and concerts for the Rotorua Daily Post. He also took the lead in bringing together the various scientists working in the town to form a Rotorua branch of the Royal Society of New Zealand and served as its president in 1955–56. He was president of the Geological Society of New Zealand in 1963–64 and took leading roles in various international scientific bodies.
Healy officially retired from the New Zealand Geological Survey in 1971, but continued his association with the Rotorua office and his consulting work in international geothermal projects. He and his wife separated during this period. In 1982 he was made an OBE for services to geology and the community. His health was beginning to fail, and after 36 years he ceased his music reviews, although he wrote several more scientific papers with younger colleagues. He finally left Rotorua to move to a rest home near his daughter in Auckland, where he died on 10 December 1994. His children took him back for a memorial service and cremation in Rotorua, where he had spent the best part of his life.