OT Jones was born at Plasnewydd, Beulah, near Newcastle Emlyn, Ceredigion. He was described in 1958, when being presented with an honorary doctorate at Aberystwyth, as a world figure in his science, the greatest geologist Wales has ever produced. The claim was made by Dr Alan Wood, then professor at Aberystwyth.
OT Jones became, in succession, professor of geology at Aberystwyth, Manchester, and finally Cambridge. He was elected a Fellow of the Royal Society in 1926, and awarded a Royal Medal in 1956. 'OT' as he was popularly known, was twice president of the Geological Society, and in 1945 the recipient of its highest award, the Wollaston medal.
"'OT' was a welsh-speaking Welshman who learned English to go to grammar school. Throughout his life he retained a deep affection for his native Wales, and although he spent the last half of his life living in England, he was often to be seen, geological hammer in hand, working in Wales. He graduated from the universities of Aberystwyth and Cambridge, and began work with the British Geological Survey in South Wales. His spare-time study of the geology around Ponterwyd and Plynlimon displayed exemplary thoroughness and won him recognition, a DSc and an invitation to become, in 1910, the first professor of geology at Aberystwyth.
When 'OT' began work, the geology of Mid Wales was poorly understood and throughout his life he focused strongly on this subject, especially on discovering the story of the lonely uplands of Central Wales. By 1912 he had explained the overall structure of the Welsh Basin, an area bounded to the north-west by the Menai Strait, and to the east and south by a great system of faults which extended from Wrexham, past Builth Wells and Llandovery, and round to Haverfordwest. He explained how, 500 to 400 million years ago, sediments flowed from a mountainous England into the deep waters of the Welsh Basin. By 1938 he was able to present a detailed structure of the Welsh Basin as an area of subsidence which accumulated sediments up to seven miles deep in places. On the award of his Wollaston Medal he was hailed 'field marshal of the Silurian rocks'.
The name of OT Jones will for ever be associated with that of WJ Pugh, his student, colleague and lifetime friend. Jones & Pugh produced some important papers about the rocks near Builth Wells, once a scene of great volcanic eruptions. Pugh followed Jones into the chairs at Aberystwyth and Manchester and, a fine administrator, became director general of the British Geological Survey.
OT Jones, though a professor in three universities, was never greatly interested in administration but was a dedicated teacher and researcher, and a brilliant field geologist. Anything related to the geology of Mid Wales attracted him: his early work extended to surveying the metal mines of the Cambrian Mountains, and late in life he was still explaining the drainage patterns and landscape development of Wales.
'OT' died at the age of 89 having produced more than 140 publications. A year before his death he published a paper describing the Welsh source of the bluestones of Stonehenge. It was written in welsh - he was a Welshman to the last."
Profile written by Colin Humphrey, chairman of Mid Wales Geology Club
Some of the facts are drawn from OTJ's biographical memoir at the Royal Society
First professor of geology at Aberystwyth, a world figure in his science and arguably the greatest geologist Wales has ever produced.
