A new biography of Marshall, Patrick appears in the Dictionary of New Zealand Biography on this site.
Marshall was one of New Zealand's outstanding geologists during the first 50 years of this century. He was born in 1869, at Sapiston, Suffolk, and attended school at Bury St. Edmonds and at Wanganui. He took degrees at Canterbury University College and Otago University, and was appointed lecturer in Natural Science at Lincoln Agricultural College in 1893. In 1896 he became a science teacher at the Auckland Grammar School, and in 1901 was appointed lecturer-in-charge of the Department of Geology at the University of Otago. He became professor in 1908, but left the university in 1917 to become headmaster of Wanganui Collegiate School. In 1924 he was appointed geologist and petrologist to the Public Works Department. He was a fellow of the Royal Society of New Zealand and president in 1924–25. He was president of the Australian and New Zealand Association for the Advancement of Science in 1946. He wrote more than 140 scientific papers on most aspects of New Zealand geology.
Marshall had a persisting interest in the history of the Pacific basin, and in 1912 proposed the term “andesite line” for its western structural margin, called subsequently the “Marshall line”. In the 1890s he described many species of insects, and this biological interest was later evident in his work on Cretaceous and Tertiary molluscs. After detailed studies of the thick sheets of volcanic rocks in the central North Island, he found that many of these rhyolitic rocks are composed of fragments of volcanic glass explosively erupted and then welded together while still hot. For these rocks he coined the name “ignimbrite” which has now a worldwide usage.
In 1900, in Auckland, Marshall married Ruth Mary Dudley by whom he had one son and one daughter. He died at Ludlam Crescent, Lower Hutt, on 10 November 1950.
by Donald Rowe Gregg, M.SC., New Zealand Geological Survey, Christchurch.
- Transactions and Proceedings of the Royal Society of New Zealand, Vol. 79 (1951) (Obit).