Walcot Gibson, a British geologist, was educated at Mason Science College, Birmingham, and at the Royal College of Science, London, obtaining the degree doctor of science (DSc). In 1889, as a young man of 25, he visited South Africa to study the geology of the Witwatersrand and adjacent areas. His study of the structural geology of the region and petrography of the rocks led him to conclude that the lower Witwatersrand beds had been repeatedly folded and affected by thrust faults, which later work by E.T. Mellor* showed not to be the case. He also concluded (correctly) that the Witwatersrand beds were younger than the gneiss and schists on their northern side, but found it difficult to unravel the relationship between the Witwatersrand beds and the overlying lavas. The results of his observations were written up in "The geology of the gold-bearing and associated rocks of the southern Transvaal" (Quarterly Journal of the Geological Society, 1892). In a subsequent paper, "Geology of the southern Transvaal" (Transactions of the Institution of Mining Engineers, 1893-1894), he considered the origin of the gold in the conglomerates, concluding that it was originally detrital, but that it had been dissolved and redistributed within the conglomerates, probably at the time of the igneous intrusions and through the action of dissolved iron salts. Some years later he contributed papers on "The age of the rand beds" (1897) and "Correlation of the palaeozoic rocks of South Africa" (1902) to the Geological Magazine.
After leaving South Africa in 1891 Gibson did geological work in East Africa from 1891 to 1893. This work formed the basis of two papers, "Geological sketch of Central East Africa" (Report of the British Association for the Advancement of Science, 1893) and "The geology of Africa in relation to its mineral wealth" (Transactions of the Federated Institution of Mining Engineers, 1897).
In 1893 he was appointed to the Geological Survey of Great Britain and later became its assistant director for Scotland, retiring in 1925. In collaboration with colleagues he compiled memoirs on the geology of various parts of the United Kingdom. He became an authority on the British coal fields, publishing several papers and memoirs on individual fields, particularly those of North Staffordshire, as well as two books: The geology of coal and coal mining (1908) and Coal in Great Britain (1920). In recognition of his expertise he was elected a Fellow of the Royal Society of London (1925), the Royal Society of Edinburgh (1921), and the Geological Societies of London and Edinburgh. He was awarded the Murchison medal of the Geological Society of London in 1924. In 1893 he became a member of the British Assiciation for the Advancement of Science. He married Annie Olive Landon in 1895, but they had no children.