Emeritus Professor John Stuart Webb, applied geochemist, dubbed “Father of English Geochemical Mapping” on his award of the Society's William Smith Medal (1981) died at Redhill, England, on 2 April 2007. He was born at Balham, London, on 28 August 1920, eldest child of George Stewart Webb and his wife Caroline Rabjohns (née Pengelly). His sister, Mona Audrey, was born in 1924. He married Jean Millicent Dyer (1920-97) in 1946. Their only child, Stuart, was born in 1950.
Educated at St. Mary's school, Balham (1925-30), Westminster City School, London (1930-38), and Imperial College (IC), London, he graduated BSc (First Class Honours) in Mining Geology (1941), having received the Murchison medal (1939), the Brough medal (1940), the Clement le Neve Foster prize and the Cullis Testimonial Fund (1941).
Briefly assistant mining geologist to the Government's Non-Ferrous Metallic Ores Committee, he then served in the Royal Engineers (1941-43), and as an economic mineralogist with the Geological Survey of Nigeria (1943-44). Awarded a Beit Scientific Research Fellowship at IC, he obtained the Judd Prize (1946) and his PhD (1947) with a study of The origin and mineral paragenesis of the tin lodes of Cornwall. Appointed Lecturer in Mining Geology (1947-55), he became Reader (1955-61) then Professor of Applied Geochemistry (1961-79).
Elected FGS (1943), he received the Daniel Pidgeon Fund (1948) to investigate Hercynian tin-tungsten mineralisation. However, aware of Scandinavian work on the application of geochemistry to the search for mineral deposits, in 1949 he began research in applied geochemistry (then an unknown subject in Britain), firstly in southern Nigeria, and then Cornwall and Derbyshire. The Nigerian work brought him into contact with Herbert Hawkes (1912-96), of the US Geological Survey's Geochemical Prospecting Unit (est. 1946). In 1952, Webb visited Hawkes and toured academic and commercial geochemical projects across North America. On his return, he proposed establishment of a British programme to provide its mining industry with geochemical methods of exploration applicable to tropical terrain.
Webb then participated with Hawkes and others in a pioneering regional survey exploring for base metal deposits over 69,000 km2 of eastern Canada, finance having been secured by Webb from London. Based on chemical analysis of the fine-grained (<0.177 mm) sieved fraction of samples of stream sediments, a sampling medium hitherto untried at that scale, it proved its effectiveness as a low-cost exploration method. Webb realised that similar, multi-element, surveys might eventually produce cost-effective geochemical maps useful to understanding of regional geology.
The Geochemical Prospecting Research Centre (GPRC) was established at IC in 1954, with Webb as its Research Director. Over the years, he pursued his objectives with single-minded tenacity, often in the face of considerable scepticism. Early studies focused on mineral prospecting, mainly in Africa, Asia and Australia, using soil and drainage sampling. Webb's multi-element regional mapping concept had its first successful test in 1960, using drainage samples collected over 7800 km2 of the Namwala-Livingstone area, Zambia. By 1966, it had also been proven in Sierra Leone.
Webb now began studies to investigate the relationship between regional geochemistry and agricultural problems in livestock, firstly in Eire in 1963, then in Devonshire, Denbighshire and Derbyshire (the first regional-scale drainage surveys in Britain) in 1965. Studies in marine mineral exploration also began in 1964, and to reflect the increasing scope of its work, the GPRC became the Applied Geochemistry Research Group (AGRG) in 1965.
By 1966, it was shown that regional drainage surveys could indicate areas of potential disease in cattle and sheep at clinical and (of particular economic importance) at sub-clinical levels. Webb recommended in 1970 that, particularly in developing countries where people tended to eat more locally-grown produce, regional geochemistry should form part of any systematic study of trace elements and human health. In 1971, AGRG began a programme to identify the severity of contamination in the urban, agricultural and marine environments as a result of pollution related to human activity. The pioneering stream sediment geochemical atlases of Northern Ireland (1973) and England and Wales (1978) confirmed Webb's view that regional geochemistry could provide an invaluable addition to conventional geological mapping.
Webb co-authored with Hawkes the classic textbook Geochemistry in Mineral Exploration (1962; 2nd edition 1979) and, with members of AGRG, the Provisional Geochemical Atlas of Northern Ireland (1973), and The Wolfson Geochemical Atlas of England and Wales (1978) which remained unequalled for some 20 years.
By his retirement (1979) he had trained over 80 PhD students. His farsighted vision of geochemical atlases as a strategic national requirement was realised in 1988 when UNESCO's International Geochemical Mapping Project was inaugurated. He was awarded the DSc (London University, 1967); the Institution of Mining and Metallurgy Consolidated Gold Fields of South Africa Gold Medal (1953) and the Society's William Smith Medal (1981); and elected Honorary Member, Association of Exploration Geochemists (1977); Fellow, Royal Academy of Engineering (1979) and Honorary Fellow, Institution of Mining and Metallurgy (1980).
Although acclaimed abroad, recognition in Britain for the importance, and pioneering nature, of the work undertaken under his guidance by the GPRC and AGRG over the years was lacking. His ex-colleagues and students feel it is shameful that he was never elected to the Royal Society.
Richard J. Howarth