Major-General Joseph Ellison Portlock (30 September 1794 — 14 February 1864) was born at Gosport and was a British geologist and soldier, the only son of Nathaniel Portlock, and a captain in the Royal Navy.
Educated at the Royal Military Academy, Portlock entered the Royal Engineers in 1813. In 1814, he took part in the frontier operations in Canada. In 1824, he was selected by Lieut-colonel (afterwards Major-General) T.F. Colby (1784-1852) to take part in Ordnance Survey of Ireland. He was engaged for several years in the trigonometrical branch and subsequently compiled information on the physical aspects, geology, and economic products of Ireland, including the Memoir for which he wrote substantial sections on productive economy.
In 1837, he formed at Belfast a geological and statistical office, a museum for geological and zoological specimens, and a laboratory for the examination of soils.